JP5321850B2 - Method for manufacturing aluminum alloy bar - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing an aluminum alloy bar which can produce a fine-sized bar in which elongation catches up upon deformation, and which has no generation of cracks, has a reduced rolling mill load, and has high characteristics with high productivity. <P>SOLUTION: An alloy having a composition comprising, by mass, 8 to 12% Si, 2 to 5% Cu and 0.2 to 1.0% Mg, and comprising 0.2 to 0.4% Fe and/or 0.2 to 0.4% Mn, and the balance aluminum with inevitable impurities is cast by a continuous casting device in a size of &le;100 mm&phiv; at a cooling rate of 1 to 15&deg;C/sec into an aluminum alloy continuously cast bar. The aluminum alloy continuously cast bar is cut by a cutting apparatus, the cut aluminum alloy continuously cast bar is subjected to homogenizing heat treatment by a heat treatment apparatus. Thereafter, the bar is subjected to surface cutting, heating at 400&deg;C to a solid phase temperature and rolling at a rolling ratio of 5 to 30% in a continuous line to produce an aluminum alloy bar of &le;20.0 mm&phiv;. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

The present invention relates to a method of manufacturing an aluminum alloy rod for cold, hot forging or cutting.

Piston parts such as car air conditioners and engines require a trend toward weight reduction, wear resistance and strength, and recently, forged products made of aluminum alloys have become more popular.
What has long been known as an aluminum alloy for pistons used in forging is J
Al-Si-Cu-Mg-Ni alloy represented by IS4032, which has a eutectic composition (about 1
(1% by mass) Si as a base to improve wear resistance and to improve strength, several mass% Cu and 1
Less than mass% Mg is added. Furthermore, in order to increase the heat resistance strength as necessary, Ni
A small amount of transition elements such as Mn and Fe are added. The aluminum alloy for pistons is generally forged by cold or hot using a cutting material of a bar and cut into a predetermined shape. Finish the part.

Also, the same kind of alloy is used for sliding members of tapes such as drums of VTRs and DATs, but these are increasing in number around 20 mmφ. These are T6 as they are
The processed material is cut and used.
This bar material is usually a so-called extruded material in which billets with a diameter of a predetermined diameter are obtained by producing billets of several hundred mmφ by continuous casting (DC casting) and performing homogenization heat treatment followed by extrusion. In this manufacturing method, it is possible to manufacture rods of any diameter in a die shape.
For example, Japanese Patent Laid-Open No. 5-287427 (Patent Document 1) discloses a method of manufacturing an extruded material from a DC cast billet.

However, since the billet for extrusion is so-called DC casting in which the material is directly water-cooled during casting, the cooling rate is faster than that of the mold casting, but the casting diameter of the base casting material is 6 inches to 10 inches.
Since this alloy, which contains a large amount of Si, is particularly inferior in heat conduction of the cast material itself, the size of the primary crystal Si is about several tens of μm at the center where the cooling rate by water cooling is slow. It crystallizes out.
This becomes remarkable especially when Si exceeds 11 mass% and approaches 12 mass%. To avoid this, the eutectic point of Si can be shifted slightly higher by adding Na, Sr, etc., but its generation is not sufficiently prevented, and generation of coarse primary crystal Si is inevitable. . Also,
Addition of Sr tends to cause a shrinkage nest in the central portion, and lowers mechanical properties in both senses.
Or, recently, a so-called continuous cast bar obtained by directly chamfering a continuous cast bar having a diameter of 100 mmφ or less has been used in many cases.

Practically, these are about 30 mmφ to 80 mmφ from the specifications of the chamfering machine. Generally, after casting, homogenization heat treatment is performed, and the surface is peeled chamfered and used as it is as a bar. Since it can be omitted, it is advantageous in terms of cost. Furthermore, since the diameter of the billet is narrower than that of the billet, the thin one is directly water-cooled, so the casting speed can be increased, and the cooling speed is increased. Improved characteristics. Alternatively, primary crystal Si, eutectic grains, intermetallic compounds, and the like, which are crystallized substances, are refined, and there is a merit that the characteristics are similarly improved. In particular, when the casting diameter is 50 mmφ or less, it becomes possible to increase the casting speed due to the small diameter, and from the improvement of the cooling rate, the primary crystal Si is generated even if the Si composition deviates slightly from the theoretical eutectic composition. It becomes difficult to do.
As forging methods, there are hot forging forging at high temperature and cold forging forging at normal temperature. Also, forging, horizontal forging forging at right angles to the longitudinal direction, cup-shaped for engine pistons, etc. The thing is called vertical forging forging in the longitudinal direction.
For example, Japanese Laid-Open Patent Publication No. 2001-259781 (Patent Document 2) discloses horizontal forging, and Japanese Patent Laid-Open No. 8-108243 (Patent Document 3) discloses vertical forging.

On the other hand, as a method for manufacturing a thin rod having a diameter of 20 mmφ or less, there is a Properti method as disclosed in Japanese Patent Laid-Open No. 2001-230366 (Patent Document 4). This is a continuous casting and rolling method in which a molten rod is poured into a wheel-shaped mold groove and the solidified material is brought into contact with the cooled wheel-shaped mold directly into a rolling mill to produce a small-diameter bar. .

JP-A-5-287427 JP 2001-259781 A JP-A-8-108243 Japanese Patent Laid-Open No. 2001-230366

In recent years, it has been used for parts that have a reduced cross-sectional area due to high pressure, such as CO ₂ compressors, or parts that are subjected to horizontal forging by bending thin ones such as gear change shift forks. There is a demand for a rod having a smaller diameter and equivalent wear resistance and strength. The small diameter means, for example, 18 mmφ or 20 mmφ.
In addition, for rotating parts such as DAT and DVD, there is a demand for wear-resistant high-strength materials for cutting with a small diameter of 20 mmφ or less.

For this application, an extruded material can be produced by casting a billet and then extruding it by an extrusion method. However, the extrusion pressure increases as the diameter decreases, so the extrusion speed must be reduced, and production Sex is worse. In order to avoid this, it is possible to make several holes on the extrusion die surface and extrude several at a time, but the extrusion tip and rear end are usually damaged by the grip part of the stretcher correction, It is necessary to discard that part by a considerable length, and the product yield deteriorates. Therefore, the productivity is considerably poor.

Furthermore, as a defect peculiar to extruded materials, especially when the degree of processing is lowered, coarse macro-recrystallized grains of about several mm are often generated in the vicinity of the extruded material surface, which is cracked during deformation during forging in the subsequent process. This is a factor that inhibits forgeability. Further, coarse recrystallization appears in the material after the solution treatment, which causes deterioration of mechanical properties of the material.

For this application, for continuous casting rods (hereinafter also referred to as “continuous casting”),
The smaller the diameter, the higher the casting speed, so the productivity will not drop. There are difficulties from the surface, and at present, products of 20 mmφ or less are not stably produced. Further, if the casting diameter is too small, the amount of surface chamfering cannot be reduced in proportion to the casting diameter, which causes a problem that the yield of the rod after chamfering deteriorates. In addition, after the above bending process,
When used for horizontal forging, there is a weak point in that it has a mechanical property weaker than that of an extruded material against bending in a perpendicular direction because it does not have a longitudinally processed structure like an extruded material.

For this application, there is a Properti method as a method for producing a thin rod having a diameter of 20 mmφ or less.
In this method, a wire rod having a diameter of 10 mmφ or less can be manufactured, but the casting method is similar to a die casting from the viewpoint of cooling. Compared with direct water cooling of the ingot at the casting outlet in normal continuous casting, the Properti method has a very slow cooling speed because it only cools the mold with water, and the cast structure of the finished bar However, the strength of the final bar is lower than that of the extruded material and continuous cast material. This manufacturing method is suitable for a material with a narrow solidification temperature range, such as pure aluminum, but in the casting of an alloy with a high concentration of Si, Cu, and Mg and a wide temperature range for solidification, the final solidification is performed. A nest is generated in the part, and remains as a rolling crack or an internal defect. It is difficult to eliminate this, and there is no reliability of the bar after rolling. In addition, since the cooling rate is slower than that of the continuous cast material, primary crystal Si, Al—Cu-based, and Al—Mn—Fe—Si-based compounds tend to crystallize coarsely.
Although attempts have been made to add additives such as Na and Sr in order to avoid primary Si crystallization, the number of shrinkage nests is increased, resulting in deterioration of characteristics.

Furthermore, the cross section of the currently used Properti casting mold is not circular, but is square or pentagonal, so the casting rod has such a cross-sectional shape and is rolled from that state. Vertical forging forging by cutting the final bar (free forging without restraining the side)
If it is performed, it may not become a perfect circle, and it is not peeled off for a forging material that requires molding dimensional accuracy.

The present invention is as follows.
8 mass% to 12 mass% of Si, 2 mass% to 5 mass% of Cu, 0.2 mass% to 1.0 mass% of Mg, 0.2 mass% to 0.4 mass% of Fe, and An alloy having a composition containing 0.2% by mass to 0.4% by mass of Mn and the balance being inevitable impurities and aluminum, with a cooling rate of 1 ° C./sec to 15 ° C./sec and a diameter of 100 mmφ or less A horizontal continuous casting step and a heat treatment before rolling that is held at 400 ° C. to 490 ° C. for 1 hour or more performed as a substitute for the homogenization heat treatment under the conditions of 470 ° C. to 495 ° C. for 1 hour to 5 hours or the homogeneous heat treatment. 20.0 mmφ including a step of applying, a step of surface chamfering or polishing after heat treatment before rolling, and a step of rolling multiple times at a rolling rate of 5% to 30% with a rolling reduction of 75% or more To manufacture the following aluminum alloy rods It is the manufacturing method of the aluminum alloy rod characterized.
In the present invention, Fe is contained in an amount of 0.2% by mass to 0.4% by mass, and / or Mn is contained in an amount of 0.2% by mass to 0.4% by mass.
The macro crystal grains of the cross-sectional macro structure are granular crystals having a maximum grain size of less than 1 mm over the entire surface.
Rolling is performed at a temperature of the base material at the rolling inlet of 400 ° C. to a solid phase temperature and a reduction rate of 75% or more.
A continuous cast rod of 100 mmφ or less is rolled after at least homogenizing heat treatment and surface chamfering treatment.
A continuous cast rod of 100 mmφ or less is rolled after at least homogenizing heat treatment, surface chamfering treatment, and preheating treatment.
It is good also as an aluminum alloy blank material for forging by drawing, cutting, and annealing.
A forging aluminum alloy blank material that is centerless polished, cut, and annealed may be used.
A continuous cast bar is repeatedly rolled a plurality of times at a rolling rate of 5% to 30%.
The rolling reduction is 75% or more.
After the continuous cast bar is cast, it is rolled after heat treatment held at 400 ° C. to (solid phase temperature −5 ° C.) for 1 hour or more.
It is possible to provide a feature that a continuous casting rod of 100 mmφ or less is used.
About the said aluminum alloy bar for forging, after a continuous casting bar | burr is homogenized heat processing, surface chamfering or surface grinding | polishing, a heating, rolling, cutting | disconnection, and drawing are performed by a continuous line.
After the homogenized heat treatment of the continuous cast bar, surface chamfering or surface polishing, heating, rolling, cutting, and centerless polishing are performed in a continuous line.
A continuous cast bar is repeatedly rolled a plurality of times at a rolling rate of 5% to 30%.
The rolling reduction is 75% or more.
After the continuous cast bar is cast, it is rolled after heat treatment held at 400 ° C. to (solid phase temperature −5 ° C.) for 1 hour or more.
Cut and anneal.
After the homogenization heat treatment of the continuous cast bar, surface chamfering or surface polishing, heating, rolling, cutting and drawing are performed in a continuous continuous line.
After the homogenized heat treatment of the continuous cast bar, it is possible to provide features such as surface chamfering or surface polishing, heating, rolling, cutting, and centerless polishing in a continuous continuous line.
About the said production line, a continuous cast bar is repeatedly rolled several times with the rolling rate of 5-30%.
The rolling reduction is 75% or more.
After casting the continuous cast bar, it can be provided with a feature that it is rolled after being heat-treated at 400 ° C. to (solid phase temperature −5 ° C.) for 1 hour or more.
In addition, the solution treatment in the present invention is (a) a solution treatment to be applied as it is to a rolled product after continuous casting, (b) a solution treatment to be performed before cutting a material that has been rolled after continuous casting, and (c). Solution treatment for hot forging after rolling after continuous casting, (d) Solution treatment in solution treatment for cold forging after rolling and further drawing after continuous casting ○ means.
The solution treatment conditions are such that after holding at 470 ° C. to 495 ° C. for 1 hour to 5 hours, the solution is quenched with water at 15 ° C. to 60 ° C., and then heat treated at 170 ° C. for 8 hours.
○ The conditions for the material treatment are such that the material is gradually cooled at a rate of about 10 ° C./hr or less after being held at 350 ° C. to 390 ° C. for 2 hours to 4 hours.

The present invention contains 8 mass% to 12 mass% Si, 2 mass% to 5 mass% Cu, 0.2 mass% to 1.0 mass% Mg, and 0.2 mass% to 0.4 mass% Fe. An alloy having a composition containing 0.2% by mass to 0.4% by mass and / or Mn of 0.2% by mass and / or Mn, with the balance being inevitable impurities and aluminum, with a cooling rate of 1 ° C./sec to 15 ° C./sec. And a step of horizontal continuous casting at a diameter of 470 ° C. to 495 ° C., before homogenization heat treatment under conditions of 1 hour to 5 hours, or before holding for 1 hour or more at 400 ° C. to 490 ° C. as a substitute for the homogeneous heat treatment An aluminum alloy rod of 20.0 mmφ or less including a step of performing heat treatment, a step of surface chamfering or polishing after heat treatment before rolling, and a step of rolling a plurality of times at a rolling rate of 5% to 30%. How to make aluminum alloy bars The aluminum alloy rod of 20.0 mmφ or less obtained by the method can avoid the decrease in tensile strength due to primary crystal Si, and the tensile strength characteristics are improved by the fine macro structure.
And since 0.2 mass%-0.4 mass% of Fe and / or 0.2 mass%-0.4 mass% of Mn are contained, solid-solution strengthening and recrystallization suppression can be aimed at.
Furthermore, since the macro crystal grains of the cross-sectional macro structure are granular crystals having a maximum grain size of less than 1 mm over the entire surface, coarse recrystallized grains are not included, and the mechanical properties of the bar are improved.
And since the temperature of the original material at the rolling entrance is 400 ° C. to (solid phase temperature −5 ° C.) or 400 ° C. to 490 ° C., the elongation catches up at the time of deformation, cracks do not occur, and the rolling mill load is small. In addition, since the rolling reduction is 75% or more, the recrystallized structure of the bar after rolling becomes a fine granular shape, and tensile properties, particularly 0.2% proof stress, are improved.
The aluminum alloy blank for forging obtained from the method for producing an aluminum alloy rod of the present invention has a low hardness after annealing and good deformability if the above-described aluminum alloy rod is drawn, cut and annealed. It becomes an aluminum alloy blank for forging with good diameter accuracy, and cold forging processability is improved.
If centerless polishing is performed instead of the drawing process, the aluminum alloy blank material for forging having good cross-sectional shape accuracy and surface smoothness is obtained, and forging workability is improved.
According to the method for producing an aluminum alloy bar of the present invention, a continuous cast bar is repeatedly rolled at a rolling rate of 5% to 30%, so that it is finer and more coarse than conventional large-diameter billets. Materials without crystallized materials such as primary Si can be easily manufactured, and by repeating multiple continuous hot workings, the work can be easily avoided while avoiding a rapid reduction, and the strength can be increased by the hot working structure. High aluminum alloy rods can be manufactured easily.
Since the rolling reduction is 75% or more, the recrystallized structure of the bar after rolling becomes a fine granular shape, and the tensile properties, particularly 0.2% proof stress, are improved.
Furthermore, since the continuous cast bar is cast and held at 400 ° C. to 490 ° C. for 1 hour or longer and then heat-treated and rolled, the elongation catches up at the time of deformation, no cracks occur, and the rolling mill load is reduced.
The method for producing an aluminum alloy bar according to the present invention may be performed by homogenizing heat treatment of a continuous cast bar, followed by surface chamfering or surface polishing, heating, rolling, cutting, and drawing in a continuous line. Can be manufactured with high productivity.
In addition, after continuous homogenization heat treatment of the continuous cast bar, surface chamfering or surface polishing, heating, rolling, cutting, and centerless polishing may be performed in a continuous line, and forging with excellent cross-sectional shape accuracy and surface smoothness. Aluminum alloy rods for forging workability.
And since a continuous cast bar is rolled repeatedly at a rolling rate of 5% to 30% multiple times, there is no crystallized material such as coarse primary crystal Si that is finer and structurally finer than conventional large-diameter billets. The material can be easily manufactured, and furthermore, by repeating the continuous hot working a plurality of times, it is possible to easily process while avoiding a rapid rolling reduction, and it is possible to easily manufacture a high-strength aluminum alloy rod by the hot working structure.
Further, since the rolling reduction is set to 75% or more, the recrystallized structure of the bar after rolling becomes a fine grain and mixed with the rolled structure, and the tensile properties, particularly 0.2% proof stress, are improved.
In addition, since the continuous cast bar is cast and then heat-treated at 400 ° C. to 490 ° C. for 1 hour or more and then rolled, the elongation catches up at the time of deformation, cracks do not occur, and the rolling mill load is reduced.
Moreover, if the aluminum alloy bar for forging obtained from the method for producing an aluminum alloy bar of the present invention is cut and annealed, it becomes a forging aluminum alloy blank with low hardness after annealing and good deformability. Forging processability is improved.
In addition, according to the production line of the method for producing an aluminum alloy rod of the present invention, even if a continuous cast rod is subjected to homogenization heat treatment, surface chamfering or surface polishing, heating, rolling, cutting, and drawing can be performed in a continuous continuous line. Well, high-performance thin rods can be manufactured with high productivity.
In addition, after the homogenized heat treatment of the continuous cast bar, surface chamfering or surface polishing, heating, rolling, cutting, centerless polishing may be performed in a continuous continuous line, and the cross-sectional shape accuracy and surface smoothness are good. It becomes an aluminum alloy bar for forging, and forging workability is improved.
And since a continuous cast bar is rolled repeatedly at a rolling rate of 5% to 30% multiple times, there is no crystallized material such as coarse primary crystal Si that is finer and structurally finer than conventional large-diameter billets. The material can be easily manufactured, and furthermore, by repeating the continuous hot working a plurality of times, it is possible to easily process while avoiding a rapid rolling reduction, and it is possible to easily manufacture a high-strength aluminum alloy rod by the hot working structure.
Further, since the rolling reduction is set to 75% or more, the recrystallized structure of the bar after rolling becomes a fine grain, and the tensile properties, particularly 0.2% proof stress, are improved.
In addition, since the continuous cast bar is cast and then heat-treated at 400 ° C. to 490 ° C. for 1 hour or more and then rolled, the elongation catches up at the time of deformation, cracks do not occur, and the rolling mill load is reduced.
In addition, the cold forged product obtained from the manufacturing method of the aluminum alloy rod of the present invention has Si of 8% by mass to 12% by mass, Cu of 2% by mass to 5% by mass, and Mg of 0.2% by mass to 1.% by mass. With a composition of 0% by mass, there is substantially no primary crystal Si, and since the macrostructure after solution treatment after forging is a fine granular crystal, a decrease in tensile strength due to primary crystal Si can be avoided and fine The macro structure improves the tensile strength characteristics.

It is explanatory drawing which shows an example of the manufacturing process of the blank material for cold forging in this invention. It is explanatory drawing which shows an example of the manufacturing process of the raw material for hot forging in this invention. It is process drawing which shows an example of the aluminum alloy stick manufacturing equipment of this invention. It is explanatory drawing which shows an example of a horizontal type continuous casting apparatus. It is explanatory drawing which shows an example of a synchronous cutting device. It is explanatory drawing which shows an example of an outer periphery removal apparatus. It is explanatory drawing which shows an example of a correction apparatus. It is explanatory drawing which shows an example of a rolling apparatus. It is explanatory drawing which shows the rolling example which rolls the rolling material by which the surface layer part was excised in multistep, and manufactures a continuous rolling material with a circular cross section. It is explanatory drawing which shows an example of a centerless grinding | polishing apparatus. It is explanatory drawing which shows an example of the cutting apparatus after rolling used by this invention. It is explanatory drawing which shows the other example of the rolling stand used for a rolling apparatus. It is explanatory drawing of the rolling roller which comprises the rolling stand shown in FIG. It is explanatory drawing which shows an example of the deformed material rolled with the rolling apparatus. It is explanatory drawing which shows an example which is rolled to a continuous cross section while reducing in diameter before shaping | molding to a discontinuous cross section. It is explanatory drawing which shows the further another example of the rolling stand which comprises a rolling apparatus. It is explanatory drawing of the rolling roller which comprises the rolling stand shown in FIG. It is explanatory drawing which shows the other example of the deformed material rolled with the rolling apparatus.

Since the aluminum alloy material of the present invention is used for a sliding member, wear resistance is required.
For this purpose, 8 to 12% by mass of Si is added as an additive element. Si becomes eutectic Si during casting, and is dispersed with a size of several μm between α crystals. This eutectic Si increases wear resistance.
When the amount of Si is less than 8% by mass, the effect is reduced, and when it exceeds 12% by mass, coarse Si as a primary crystal starts to crystallize. For example, when particles having a particle size of about 100 μm are scattered, they remain after rolling and cause a decrease in strength or impair machinability. It is preferable that the primary crystal is substantially absent. This substantial means that when the cross section is randomly micro-inspected, it is not found with a probability of 95% or more.

Cu improves the strength by precipitation hardening and strengthens the alloy matrix by a solution treatment after forging. When the amount of Cu is less than 2% by mass, the effect is small, and the effect increases as the amount increases.
Problems in manufacturing such as cracking during forging will come out.

Similarly, Mg contributes to the improvement of mechanical properties due to precipitation age hardening by solution, but it is preferable that the content of Mg is 0.8.
If it is less than 2% by mass, the effect is poor, and if it exceeds 1% by mass, the oxide during casting increases, the mechanical properties deteriorate, and cracking during forging tends to occur.

Fe and Mn are used as solid solution strengthening and recrystallization suppression. When the casting conditions, for example, the casting diameter is large and the solidification rate is slow, an intermetallic compound coarser than the Si eutectic may be crystallized, which is a factor that hinders and lowers the mechanical properties. When Fe and Mn are less than 0.2% by mass, the effects of solid solution strengthening and recrystallization suppression are diminished, and when they exceed 0.4% by mass, the hardness during annealing increases or the crystallization occurs. Inhibits deformation at the time of cold forging, and it is preferable to suppress the maximum to 0.4% by mass as necessary.

As a base material for rolling, 100 mmφ or less (preferably 40 mmφ to 100 mm) of the above composition
φ, more preferably 45 mmφ to 80 mmφ. It is preferable to roll using a continuous casting product. Continuous casting usually exceeds 100 mmφ, but there are many vertical castings.
In the case of 00 mmφ or less, it is cast in a vertical type or a horizontal type (horizontal). In either case, since the casting is cast while directly cooling with water during casting, the cooling rate is faster (larger) than that of a die casting, a propel type, or the like. The cooling rate is, for example, 1 ° C./sec or more (more preferably 4 ° C./sec.
~ 15 ° C / sec. ) Is preferred. Further, since a billet having a large diameter is not cast as in the case of casting of an extruded material, it is difficult to form a coarse crystallized product that hinders mechanical properties.
On the other hand, if the material exceeds 100 mmφ, the casting speed cannot be increased, the cooling speed becomes slow, and the cast structure becomes rough. Along with this, DAS (secondary dendrite arm space) increases, and the mechanical properties after the rolling process deteriorate. The average DAS is preferably 15 μm or less.
The size of DAS is described in, for example, “Light Metals (1998), vol.
38, no. 1, p. 45 ”can be measured according to the“ Dendrite arm spacing measurement method ”.
Alternatively, when Si increases to near 12% by mass, primary Si is likely to be crystallized, and the primary crystal Si remains after rolling, which reduces mechanical properties and reduces the saw blade and tool life during cutting and cutting. Reduce significantly. Accordingly, the thinner the casting diameter, the higher the casting speed and the higher concentration composition does not cause crystallization of primary crystal Si. Therefore, the thinner the casting diameter, the better, but casting at 50 mmφ or less is preferable.

Moreover, when Fe, Mn, etc. are added, when they increase (for example, exceeding 0.4 mass%), the crystallization thing containing Fe, Mn, etc. of the tendency similar to primary Si is coarsened, May crystallize. Therefore, the continuous cast material before rolling is preferably cast at 100 mmφ or less in order to reduce the crystallization gap by increasing the cooling rate to make DAS finer. The most suitable is 50 mmφ or less, and the thinner, the finer the internal cast structure and the finer the DAS, and finally the tensile mechanical properties after T6 are improved. Furthermore, since the number of rolling operations can be reduced, the load applied during rolling can be reduced during production, and the machine capacity can be reduced.

The average particle diameter of eutectic Si is preferably 3 μm or less on average in order to improve mechanical properties. Therefore, a continuous casting material having a diameter of 50 mmφ or less is preferable.

Note that the continuous cast material before rolling is preferably subjected to a homogenized heat treatment because the deformability at a high temperature is increased. Homogenization heat treatment is performed for several hours at a temperature about 10 ° C. to 20 ° C. lower than the solidus line (
For example, 470 ° C. to 495 ° C., 1 hour to 5 hours depending on the alloy composition. ) Is held and then air-cooled.
When homogenization heat treatment cannot be performed, heating before rolling (for example, 400 ° C to 4 ° C depending on the alloy composition)
90 ° C. ) For 1 hour or more can be used as a substitute for homogenization heat treatment.

The continuous cast material before rolling is preferably surface-faced. When chamfering is not performed, surface cracks may occur during rolling due to segregation of the very surface. Face milling usually has a length of up to about 1 m, and lathe machining may be used. However, it is preferable to perform machining with a peeling machine because it is possible to chamfer long objects with high accuracy and automatically at high speed. . When using a peeling machine, it is advantageous because inspections such as eddy current flaw detection and ultrasonic flaw detection for defect inspection can be automatically performed continuously. When the surface casting surface is relatively good, the segregation layer on the surface may be removed by polishing such as centerless polishing instead of chamfering.
The cross-sectional shape can be adjusted to a circular shape by surface chamfering. Those having a circular cross-sectional shape are preferred in the subsequent processing.

In addition, when homogenizing heat treatment of a continuous cast material, it is preferable to perform it in the process before peeling, because it lowers the peeling load resistance and improves the surface chamfering.

Next, the continuous cast material obtained as described above is put into a rolling process step as a base material for rolling.
The rolling reduction is expressed as the ratio of the cross-sectional area.

Calculate as
When the rolling reduction is 75% or more, the cross-sectional recrystallized structure of the bar after rolling becomes fine particles (for example, an average particle size of 50 μm to 500 μm, more preferably 50 μm to 100 μm), coarse particles of 1 mm or more, and columnar shapes Goods are not seen. As a result, the structure after T6 is not coarsened, and the tensile properties, particularly 0.2% proof stress, are improved.

As the rolling mill, a multi-stage rolling mill that continuously rolls is used. For example, 2 directions or 3
It passes between rollers opposed to each other, and the previous stage and the next stage are arranged so that they are rotated by 90 degrees in the case of two directions and rotated by 60 degrees in the case of three directions. In this case, it is also possible to apply and use the aforementioned Properti type rolling mill so as to meet the object of the present invention.

For rolling, it is preferable to process the material on the front side at a high temperature because the load on the rolling mill is reduced. In the present alloy, the rolling is performed at the rolling entrance at a temperature lower than the solid phase temperature of the original material, but is preferably 5 ° C. lower than the solid phase temperature. This is because if the temperature is too high, elongation cannot catch up during deformation and grain boundary cracking may occur. Conversely, if the temperature is too low, the rolling mill load increases, and in extreme cases, rolling may not be possible. In this alloy, the temperature of the base material at the rolling entrance is preferably 400 ° C. or higher. When rolling in multiple stages, looking at the balance between the volume of the material and the amount of rolling oil, the stage from half to the previous stage makes the rolling oil squeezed so that the temperature drop is relatively small, and the further the stage goes It is preferable to apply a large amount of rolling oil. The outlet temperature is preferably 100 ° C to 300 ° C.

Efficient production can be achieved by heating in a batch furnace before rolling, taking out high-temperature rods one by one, or placing an induction heating furnace in the previous stage and heating and rolling continuously. Is possible.

The rolling rate per stage of the rolling mill is 5% to 30%. Here, the rolling rate is a cross-sectional area ratio before and after processing in each stage.
Also, rolling oil (coolant oil) is caused to flow on the roller surface in order to prevent seizure with the rolling roller. Therefore, at the end of rolling, the temperature is 100 ° C to 300 ° C depending on the diameter. If the outlet temperature is too high, the material may be damaged, so it is preferable that the outlet temperature is not too high. The outlet temperature is preferably 200 ° C. or lower. Therefore, if necessary, it is necessary to cool the material as it leaves the rolling mill.

The rolled material obtained in this way has both a rolled structure and a recrystallized structure, and a high-rolled structure that is not only a complete recrystallization remains, so that it is suitable when an annealing heat treatment is performed in the subsequent process. The hardness is reduced to a range, and the crystal grains are less than 1 mm. As a result, workability under cold conditions is improved, and cold work materials (for example, forging materials, drawing materials, It is preferable as a plastic working material and a cutting material.

In the conventional case where a simple cast material is used as it is, since the rolling process is not added, the hardness after annealing is much higher, whereas the bar material of the present invention has a low hardness after annealing. Become.

In the case of conventional extruded materials, since the extrusion process is performed at a high temperature, a coarse recrystallized structure is likely to occur in a portion with a low degree of processing. Furthermore, coarse recrystallization appears in the material after solution treatment, and the material In contrast, the rod of the present invention hardly causes a coarse recrystallized structure, and coarse recrystallization hardly appears in the solution-treated material.

In addition, the bar material by the conventional Properchi method has a rough cast structure, and the strength of the final bar is an extruded material,
Although it falls compared with a continuous casting material, the bar material of this invention has a fine cast structure, and the intensity | strength of the last bar material does not fall. Further, in the case of a bar material made by the Properti method, when a high concentration of Si, Cu, and Mg is an alloy having a wide temperature range during solidification, a nest is generated in the final solidified portion and remains as a rolling crack or an internal defect. However, since the bar of the present invention is an alloy having a high concentration of Si, Cu, and Mg and a wide temperature range during solidification, no solidification foci are generated, so it remains as a rolling crack or an internal defect. There is nothing. In addition, for the rod material by the Properti method, the final bar is cut and vertical forged forging (
Free forging without restraining the side. ), The bar of the present invention may be produced by rolling a continuous cast bar having a round cross section or a base material having a round cross section by surface chamfering. Therefore, when the final rod is cut and vertical upsetting forging is performed, a preferable circular shape can be obtained, which is suitable as a forging material that requires accuracy in forming dimensions.

The rolled material of the present invention can be cut to the required length immediately after leaving the rolling mill. In this case, a regular cutter may be used when the exit speed is slow with a thick object, but when the exit speed is fast with a fine article, it can be cut continuously with a shear cutter or a rotary cutter. You may cut it. If it is a thin object, it can be wound into a coil. Since this affects the conditions under which the diameter and temperature can be taken up, it is preferable to determine whether the cutting or the coil is performed according to the rolling exit conditions and the use conditions of the forging machine or the cutting machine.

It is also possible to attach an inspection device such as an eddy current flaw detector for defect inspection after rolling,
In general, there are many types that penetrate the search coil. In this case, if the rolling exit temperature is too high, the search coil is damaged, so the rolling exit temperature is preferably 200 ° C. or lower.

As a material for hot forging, a thin material having a diameter of 20 mmφ or less after rolling is often used for horizontal forging (for example, burr forging). It can be about several mm (for example, 0.2 mm to 0.3 mm), and can be used as it is after being cut into a required length while being rolled. In this case, the roundness of the cross section is not a problem, and the rolled cross section only needs to be a constant cross section in order to align the weight per unit of the standard cut product.

When used as a material for cold forging, it is usually necessary to manage the volume relationship between the material and the molded product because a sliced material is put into a mold and vertical forging (for example, closed forging) is performed. In addition, the dimensional (diameter) accuracy of the material is severe. Therefore, when it is impossible to obtain the required accuracy with only the diameter accuracy of the rolling roller, it is necessary to perform drawing in a subsequent process. A diameter accuracy of about ± 0.1 mm or less can be achieved by drawing. In addition, centerless polishing can be used instead of this drawing step. This is to polish the surface by passing between rotating wheels.
The same accuracy as the drawing and the smoothness of the surface can be obtained. Further, in the case of drawing, it is necessary to discard the tip portion for pulling the tip, but centerless polishing is preferable because this is not necessary.

When cold forging is performed, the deformability is improved by reducing the hardness of the material as much as possible. For this reason, it is preferable to heat-treat the sliced blank material for annealing. Usually, in this alloy, the hardness is lowered by holding at a temperature of about 350 ° C. to 390 ° C. for several hours (for example, 2 hours to 4 hours) and performing furnace cooling (preferably about 10 ° C./hr or less). can get. In particular, by annealing the material after rolling as in the present invention, precipitation during annealing is promoted, and a material having a low hardness and good deformability is better than annealing a face-cast material of a continuous cast material without rolling. Is obtained.

Although the above has been described mainly with respect to the round bar material, by changing the roller shape in the rolling stage, it is also possible to produce a long bar having an irregular cross section.

An example of the manufacturing process of the blank material for cold forging is shown in FIG.
Moreover, an example of the manufacturing process of the raw material for hot forging is shown in FIG.
In FIG. 2, if a continuous soaking furnace is used in the heating process, both heating and homogenization can be performed. When the temperature is lowered to the rolling temperature without the furnace cooling process, the raw material can be taken out and rolled as it is. It is.

The apparatus and process of the present invention will be described below.
<< Description of equipment and process >>
<Integrated line: melting holding furnace → molten metal processing equipment → continuous casting equipment → synchronized cutting equipment → heat treatment equipment (
Homo) → peeling device → correction device → nondestructive inspection device → preheating device → rolling device → standard cutting device>

FIG. 3 is a process diagram showing an example of an aluminum alloy bar manufacturing facility of the present invention.
In FIG. 3, a melting and holding furnace (melting step) is for melting a raw material for an aluminum alloy to obtain a molten aluminum alloy.
The molten metal treatment apparatus (molten treatment process) is for removing in-line the aluminum oxide and hydrogen gas in the molten aluminum alloy from the melting and holding furnace.
The continuous casting apparatus (continuous casting process) is a horizontal continuous casting apparatus that casts an aluminum alloy continuous casting rod from the molten aluminum alloy supplied from the molten metal processing apparatus, as will be described later. .
The synchronized cutting device (cutting step) is for cutting an aluminum alloy continuous cast bar cast by a continuous casting device to a fixed size as described later.
The heat treatment device (heat treatment step) is for homogenizing heat treatment of a fixed aluminum alloy continuous cast bar cut by a synchronous cutting device.
The peeling device [periphery removing device (periphery removing step)] removes the outer peripheral portion of the aluminum alloy continuous cast bar heat-treated by the heat treatment device.
The straightening device [bending straightening device (rectifying process)] is capable of accurately inspecting the inside of an aluminum alloy continuous cast bar when the inside of the aluminum alloy continuous cast bar heat treated by the heat treatment device is inspected by the following nondestructive inspection device. Therefore, the bending of the aluminum alloy continuous casting rod is corrected.
The nondestructive inspection device (nondestructive inspection step) is for inspecting whether or not there is a defect inside the aluminum alloy continuous cast bar whose curvature has been corrected by a correction device.
A preheating apparatus preheats the rod material thrown into a rolling apparatus.
The rolling device forms a pre-heated bar material into a continuous rolled material by rolling.
A regular cutting apparatus manufactures a regular rolling material by cutting the continuous rolling material formed by the rolling apparatus.

Depending on the product specifications of the aluminum alloy bar, the correction device and the nondestructive inspection device can be omitted.
Moreover, it is also possible in the order of melting holding furnace → molten metal processing apparatus → continuous casting apparatus → synchronized cutting apparatus → peeling apparatus → heat treatment apparatus (also serving as homogenization and homogenization) → rolling apparatus → standard cutting apparatus.
Then, in FIG. 3, continuous casting of the cast material in the continuous casting apparatus is performed by disposing a melting and holding furnace, a continuous casting apparatus, a heat treatment apparatus (homo), a peeling apparatus, a rolling apparatus, and a regular cutting apparatus as a minimum system. , Heat treatment by a heat treatment device (homo), surface layer cutting of a cast material in a peeling device, formation of a continuous rolled material by rolling a bar material in a rolling device, production of a fixed rolling material by cutting a continuous rolled material in a fixed cutting device Can be performed continuously.

<Continuous casting equipment>
FIG. 4 is an explanatory view showing an example of a horizontal continuous casting apparatus.
In FIG. 4, 202 indicates a tundish for storing the molten aluminum alloy 1, and an opening 203 is provided on the side wall.
Reference numeral 204 denotes a refractory plate-like body, which is attached to the outside of the tundish 202 so as to surround the opening 203, and a pouring hole 205 communicating with the opening 203 is provided.
Reference numeral 302 denotes a cylindrical mold constituting the horizontal continuous casting apparatus 301, which is attached to the refractory plate 204 so that the central axis is substantially horizontal, and the circumference between the mold 302 and the molten aluminum alloy 1. Lubricating oil for supplying a lubricating oil on the circumference between the gas supply path 303 for supplying gas from between the refractory plate-like body 204 and the mold 302 and the circumference between the mold 302 and the aluminum alloy continuous casting rod 2 A supply path 304 and a cooling water supply path 305 for supplying cooling water to the periphery of the aluminum alloy continuous casting rod 2 at the outlet are provided.

Next, casting of the aluminum alloy continuous casting rod 2 will be described.
The molten aluminum alloy 1 supplied into the tundish 202 from the molten metal treatment apparatus (not shown) is contained in the mold 302 held from the pouring hole 205 of the refractory plate-like body 204 so that the central axis is substantially horizontal. And is forcibly cooled at the outlet of the mold 302 to form the aluminum alloy continuous casting rod 2.
Here, the composition of the molten aluminum alloy 1 stored in the tundish 202 will be described.
In particular, the molten aluminum alloy has a Si content of 8% by mass to 12% by mass (preferably 9% by mass to
11% by mass. ) Since the aluminum and silicon contained in the aluminum alloy continuous casting rod 2 form a layered structure called a fine eutectic, the mechanical properties are excellent and the wear resistance is improved by hard silicon. Therefore, it is preferable.
The composition ratio of the alloy components of the aluminum alloy continuous casting rod can be confirmed by a photoelectric photometric emission spectroscopic analyzer as described in JIS H 1305, for example.
The horizontal continuous casting apparatus has been described. However, as long as the cooling rate can be increased and a bar-shaped casting can be performed, the vertical continuous casting apparatus, the DC continuous casting apparatus, the hot top casting apparatus, and the gas pressurization type are also available. A hot top casting apparatus, an electromagnetic casting apparatus, etc. can be used.

<Synchronized cutting device>
5 (a) and 5 (b) are explanatory views showing an example of the synchronous cutting device, FIG. 5 (a) is a side view,
FIG. 5B corresponds to a plan view.
In FIG. 5, reference numeral 306 denotes a guide roller, which is provided near the exit of the mold 302 and supports and guides the row of aluminum alloy continuous cast bars 2.
Reference numeral 307 denotes a pinch roller which is provided downstream (adjacent to the guide roller 306 in the direction in which the aluminum alloy continuous casting rod 2 moves, hereinafter the same), and sandwiches the row of aluminum alloy continuous casting rods 2 with the upper and lower rollers. Then, the row of aluminum alloy continuous cast bars 2 is pulled out and transferred at the same speed as the casting speed of the mold 302 by a driving mechanism (not shown).
Reference numeral 402 denotes a synchronous clamp mechanism, which is provided downstream adjacent to the pinch roller 307,
The row of aluminum alloy continuous casting rods 2 is pressed and held by a hydraulic mechanism or released.
Reference numeral 403 denotes a drive mechanism, which is provided below the tuning clamp mechanism 402. The tuning clamp mechanism 402 is upstream along the row of aluminum alloy continuous casting rods 2 (in the direction opposite to the direction in which the aluminum alloy continuous casting rod 2 moves, The same shall apply hereinafter) and the movement of the tuning clamp mechanism 402 is made free.
Reference numeral 404 denotes a support roller, which is provided on the downstream side that does not hinder the movement of the tuning clamp mechanism 402, and supports the row of aluminum alloy continuous cast bars 2.
Reference numeral 405 denotes a moving frame, which is provided downstream of the support roller 404 and reciprocates along the row of aluminum alloy continuous cast bars 2.
Reference numerals 406A and 406B denote rails, and an aluminum alloy continuous cast bar 2 is attached to the movable frame 405.
Are provided at predetermined intervals perpendicular to the row.
Reference numerals 407A and 407B denote motors, and the motor 407A is provided on the movable frame 405 on the outer side in the width direction of the row of aluminum alloy continuous cast bars 2 in correspondence with the rail 406A.
7B is provided on the movable frame 405 on the outer side in the width direction of the row of aluminum alloy continuous cast bars 2 corresponding to the rail 406B.
Reference numerals 408A and 408B denote cutting machines, which are driven by the motors 407A and 407B to cut half of each row of the aluminum alloy continuous cast bar 2.
Reference numeral 409 denotes a movable gantry clamping mechanism, which is provided on the movable gantry 405 and presses and holds the row of aluminum alloy continuous cast bars 2 by a hydraulic mechanism or releases it.
Reference numeral 410 denotes a drive mechanism, which is provided below the movable mount 405 and drives the movable mount 405 upstream along the row of aluminum alloy continuous casting rods 2 or allows the movable mount clamp mechanism 409 to move freely. It is.
Reference numeral 411 denotes a length detector which is attached to the downstream side of the movable frame 405 and detects the length of the aluminum alloy continuous cast bar 2 to be cut.
The horizontal continuous casting apparatus 301 includes a mold 302 to a pinch roller 307.
The synchronized cutting device 401 includes a synchronized clamp mechanism 402 to a length detector 411.

Next, the cutting of the rows of aluminum alloy continuous cast bars 2 will be described.
First, the row of aluminum alloy continuous casting rods 2 coming out of the mold 302 is formed by guide rollers 306.
After being supported and guided by, it is pinched in a row by a pinch roller 307 and transferred at a casting speed by a driving force of a driving mechanism (not shown).
The row of aluminum alloy continuous casting rods 2 to be transferred is pressed and clamped by the tuning clamp mechanism 402. At this time, since the drive mechanism 403 freely moves the tuning clamp mechanism 402, the tuning clamp mechanism 402 moves as the row of the aluminum alloy continuous casting rods 2 moves.
During this time, the movable frame 405 is moved upstream by the drive mechanism 410, that is, the pinch roller 3.
Is moved in the direction of 07, reaches a predetermined position and stops, and the driving device 410 is moved to the moving frame 40.
5 is in a standby state where it can move freely.
The tip of the row of aluminum alloy continuous casting rods 2 being transferred is a length detector 411.
At the same time, the moving gantry clamp mechanism 409 grips the row of aluminum alloy continuous casting rods 2 and the cutting machines 408A and 408B operate, but the moving gantry 405 moves together with the row of aluminum alloy continuous casting rods 2. The aluminum alloy continuous cast bar 2 is cut at right angles to the transfer direction.
When the cutting is completed, the cutting machines 408A and 408B return to their original positions, and at the same time, the movable frame clamp mechanism 409 is released, and the movable frame 405 is moved upstream by the drive mechanism 410 to reach a predetermined position. Then, the driving device 410 becomes free to move and enters a standby state.
On the other hand, the tuning clamp mechanism 402 releases the row of aluminum alloy continuous casting rods 2 immediately after the movable gantry clamp mechanism 409 grips the row of aluminum alloy continuous casting rods 2, and is moved upstream by the drive mechanism 403. While reaching a predetermined position and stopping, the drive device 403 is free to move and enters a standby state.
In this standby state, the synchronized clamp mechanism 402 is finished immediately after the cutting of the rows of the aluminum alloy continuous cast bars 2 by the cutting machines 408A and 408B is completed, and immediately before the movable frame clamp mechanism 409 releases the rows of the aluminum alloy continuous cast bars 2. The row of the alloy continuous casting rods 2 is gripped and moved together with the row of the aluminum alloy continuous casting rods 2.

<Heat treatment equipment (homogenization treatment equipment)>
There are two types of homogenization furnaces: batch type and continuous type.
In the batch type, the material temporarily packed in a cart is loaded, and the cart is inserted into the furnace from the side. After raising the temperature and holding, it is usually replaced with an air-cooled cooling furnace. After cooling to room temperature in this cooling furnace, remove from the cart. In the case of the batch type, the temperature at the time of temperature rise varies depending on the loading position and the packing position, so it takes time until the whole material reaches the holding temperature after the atmosphere reaches the holding temperature. Accordingly, although the holding time can vary depending on the location, there is no problem if the setting is made so that the entire time is longer than a certain time.
In the continuous type, materials are sequentially inserted into the furnace from the entrance by a conveyor or the like, and kept at a constant temperature while passing through the soaking zone. Then, it passes through the cooling zone and cools to room temperature. Since the material is not packed, it moves in the same way in the soaking zone, so there is little variation in the temperature history of all materials. Moreover, since it can be taken out continuously, it is easy to make as a continuous line from the casting in the previous process to the peeling in the subsequent process.

<Peeling device (periphery removing device)>
Since the segregation layer generated on the surface has a high alloy component concentration, the subsequent rolling tends to cause cracks. If cracks stop in the segregation layer, they can be removed by peeling the cast rolled material, but if the cracks propagate to the inside of the cast rolled material, they cannot be removed by peeling, and there is no product value. Become. Therefore, if the segregation layer is removed before rolling, generation of cracks due to rolling can be prevented. Moreover, the lifetime reduction of the cutting blade which arises by cutting a rolling material with a segregation layer can also be prevented, and the quality of a cut surface can also be improved.

6 (a) and 6 (b) are explanatory views showing an example of an outer periphery removing (peeling) device. FIG.
a) is a perspective view excluding the cutting blade drive mechanism, and FIG. 6B corresponds to a side view showing the support roller.
In FIG. 6, reference numeral 611 denotes a conveying roller, which is composed of four parts that convey and hold the aluminum alloy continuous casting rod 3 in a vertically divided manner when viewed from the side, and the adjacent conveying rollers 611 communicate with each other. The predetermined interval is set in accordance with the length of the.
Reference numeral 616 denotes a cutting blade, which is arranged on the circumference of the aluminum alloy continuous casting rod 3 conveyed in the longitudinal direction by the conveying roller 611 so that the outer peripheral portion can be cut without being left uncut and divided by 90 degrees. The rotary blade is rotated by a cutting blade drive mechanism (not shown).
Reference numeral 617 denotes a support roller that supports the aluminum alloy continuous casting rod 3 whose outer periphery is removed so as not to rattle, and 618 denotes a support roller that supports the aluminum alloy continuous casting rod 4 whose outer periphery is removed so as not to rattle, The aluminum alloy continuous cast bars 3 and 4 are supported in 60 degree divisions.
The outer periphery removal (peeling) device 601 includes a conveyance roller 611, a cutting blade 616 to a support roller 618, and the like.

Next, the outer periphery removal of the aluminum alloy continuous casting rod 3 using this apparatus 601 will be described.
First, each conveyance roller 611 is rotated by a driving mechanism (not shown), and the cutting blade 616 is rotated by a cutting blade driving mechanism (not shown).
Then, by introducing the aluminum alloy continuous casting rod 3 between the conveying rollers 611, the aluminum alloy continuous casting rod 3 is sequentially sent to the left side by the conveying roller 611, and the outer peripheral portion (for example, non-uniform structure) is rotated by the rotating cutting blade 616. Is cast without leaving uncut portions, and the aluminum alloy continuous cast bar 4 having a predetermined outer diameter is obtained.

According to this outer periphery removing device, the object to be cut (aluminum alloy continuous cast bar) does not rotate, the cutting mechanism (cutter head, cutting blade) rotates, and the object to be cut is less than a conventional lathe. Since the driving force is given by the pair of transport rollers and the cutting is completed by passing through the cutting mechanism, it can be continuously processed with zero handling time. Although the length of the cutting body is finite, this peeling process is theoretically infinite in the length of the body to be cut, so that the productivity is good and a peeling machine is advantageous. In particular, in the case of a small diameter material (for example, 20 mmφ to 80 mmφ), the workpiece itself has a large bend, and therefore, the peeling process is more advantageous than the turning process of the object to be cut, which is liable to cause uncut material.
In addition, it is preferable that chips generated when removing the casting surface in the outer periphery removing process are continuously crushed and returned to the melting process. For example, the chips are made fine using a chip crusher, and the fine chips are pumped using pressurized air. As a result, since the generated chips are temporarily stored and there is no need to carry the chips stored by the operator with a hook lift or the like, the continuous continuous operation can be more easily performed.

The peeling device preferably has a roundness of cross section of less than 0.1 mm as a result of cutting the surface of the continuous cast bar. Here, the roundness is defined as the maximum diameter difference including the cross section and the length direction. This is because if the roundness exceeds this range, there is a risk that the inspection accuracy of eddy current flaw detection as a non-destructive inspection in the subsequent process may be reduced and the rolling length may be varied.

<Correction device>
The cast aluminum alloy continuous cast bar has a bend in the length direction. When heat treatment is performed after casting, the bend is further increased. For example, in a small diameter of 60 mmφ or less, it is put into a nondestructive inspection apparatus. At this time, it becomes a level that cannot be ignored. For example, the bend is 5m
When m / 1000 mm or more, there is a possibility that the detection results may vary due to variations in the gap between the detector and the side of the aluminum alloy continuous casting rod, which is the surface to be inspected, in an ultrasonic inspection apparatus as a nondestructive inspection apparatus. . In addition, when passing through a guide bush provided at the inlet of a non-destructive inspection device or the like for suppressing gap variation, the surface of the aluminum alloy continuous casting rod may be damaged by contact with the guide bush. There is.
Here, 5 mm / 1000 mm means that the bending amount is 5 mm with respect to the longitudinal direction of 1000 mm.
It means that.

For example, if the bend is 5 mm / 1000 mm or more, the backlash of the aluminum alloy continuous casting rod is large, and the material permeability when passing through the guide bush is deteriorated.
Problems such as detection of bottom waves as defect echoes arise. Therefore, the bend is 5mm / 1.
It is desirable to be less than 000 mm (more preferably 2 mm / 1000 mm or less). As a result, stable and continuous operation can be performed more easily.

As described above, it is preferable to use a roller straightening machine as a straightening machine for correcting the bending of the aluminum alloy continuous casting rod. This is to reduce bending by passing an aluminum alloy continuous cast rod between a roller whose side surface (circumferential surface) is concave in the axial direction and a roller whose side surface (circumferential surface) is convex in the axial direction. It is. The processing conditions are set by adjusting the roll angle, the rolling load, and the rotation speed of the roller. As a result, since bending is reduced, troubles in loading and unloading to the apparatus during transportation are reduced, so that continuous continuous operation can be performed more easily.

In addition, if the aluminum alloy continuous cast rod, which is a material to be cut in the outer peripheral surface machining in the outer peripheral removal (peeling) process, has a bend of, for example, 5 mm / 1000 mm or more, eccentricity occurs during outer peripheral cutting, and the outer peripheral portion remains uncut. Or cause uneven cutting. Therefore, in order to continuously produce an aluminum alloy continuous cast bar having a constant surface quality, the bending of the aluminum alloy continuous cast bar is less than 5 mm / 1000 mm (preferably,
2 mm / 1000 mm or less. It is desirable to put in the outer periphery removing step in the state of

7A and 7B are explanatory views showing an example of the correction device, FIG. 7A is a plan view, and FIG.
(B) corresponds to a side view.
In FIG. 7, reference numeral 702 denotes a roller pair, which is composed of a pair of upper and lower concave rollers 703 and convex rollers 704 arranged so that the axes intersect when viewed in a plane. It is set to an optimum value corresponding to the outer diameter of the aluminum alloy continuous casting rod 4 to be processed.
α represents a roll angle.
The straightening device 701 includes a roller pair 702 and the like.

Next, correction of the bending of the aluminum alloy continuous casting rod 4 using the present apparatus 701 will be described.
First, at least one of the rollers 703 and 704 of each roller pair 702 is rotated by a drive mechanism (not shown).
Then, for example, by introducing the aluminum alloy continuous cast rod 4 between the rollers 703 and 704 of the roller pair 702 at the right end, the aluminum alloy continuous cast rod 4 is sent to the left side while rotating, and the bending is corrected. , Corrected to a perfect circle.

<Non-destructive inspection equipment>
If there is a defect inside the aluminum alloy continuous cast rod that has been corrected in this way,
Since a rolled product becomes a defective product, it is desirable to inspect whether or not there is a defect inside the aluminum alloy continuous cast bar with a nondestructive inspection device.
It is preferable to use an ultrasonic flaw detection inspection apparatus as this nondestructive inspection apparatus. This is because the ultrasonic flaw detection can perform an internal inspection based on the behavior of the ultrasonic inspection object irradiated from the probe, that is, the aluminum alloy continuous casting rod. Other internal inspection methods include X-ray transmission inspection, but it takes time to manage the equipment, such as the need for a high-voltage device to generate X-rays. In addition, the X-ray transmission inspection has a high detection capability for defects having a volume such as a foreign substance in principle, but the detection capability for defects such as cracks that have a small volume and greatly affect quality characteristics is inferior.
On the other hand, ultrasonic flaw detection has a high detection capability even for cracks, and by processing the detected electrical signal, automatic determination of defects can be easily made compared to X-rays that require image processing,
Highly accurate inspection and stable inspection.

<Heat treatment equipment (preheating)>
A batch processing furnace or a tunnel type induction superheating furnace can be used.
Moreover, it is preferable that the temperature of the cast material (aluminum alloy continuous cast bar) introduced into the rolling device is maintained at a certain level. If it is high temperature, the deformation resistance at the time of rolling will be reduced, the load of a rolling roller will become small, and it will become difficult to produce wear and damage of a rolling roller. However, when the temperature is excessively high, the deformation resistance becomes too small, and the surface shape of the rolling roller may be difficult to be transferred. Moreover, in order to raise | generate a grain boundary crack, the temperature of the cast material introduce | transduced into a rolling device has preferable 400 to (solid phase temperature), and 450 to 480 degreeC is preferable especially in this alloy.

<Rolling equipment>
8 (a) and 8 (b) are explanatory views showing an example of a rolling device, and FIG. 8 (a) is the front side, FIG.
(B) corresponds to the rear side.
In FIG. 8, a rolling device 1001 includes a plurality of rolling rollers 10 for forming a continuous cross section.
The rolling stand 1011A includes 12A as a set, and the rolling stand 1011B includes a plurality of rolling rollers 1012B for forming a continuous cross section.
As shown in FIGS. 8A and 8B, the rolling stands 1011A and 1011B have a rotating shaft 1
Three rolling rollers 1012A and 1012B that rotate at 016A and 1016B and have flange portions 1014A and 1014B at both ends in the rotational direction are arranged every 120 degrees and rolled from three directions. Further, a plurality of installed rolling stands 1011A, 1011
Since the arrangement of the rolling rollers 1012A and 1012B of B is changed in the next stage,
The rolling direction is different from the preceding stage. And rolling roller 1012A, 1012B
Rolling rollers 1012A, 10 of a plurality of rolling stands 1011A, 1011B.
Since the diameter of 12B is increased as it goes to the subsequent stage, the diameter of the rolled material (aluminum alloy continuous cast bar 4) is gradually reduced. In addition, a method of gradually changing the shape of the forming surface of the rolling roller, for example, gradually changing the radius of curvature may be used.
In addition, the rolling stand which comprises a rolling apparatus is not limited to two, What is necessary is just at least 2 or more. And the number of rolling rollers which comprise one rolling stand is not limited. Further, rolling is performed at a rolling rate of 5% to 30% in one rolling stand. In the rolling of a plurality of stages, it is preferable in terms of reducing the deformation resistance that the rolling rate is large on the starting side and gradually decreases toward the regular cutting side. Moreover, since the roundness of the cross section of the obtained rolled material (aluminum alloy continuous cast bar) is improved, it is preferable.

In FIG. 9, rolling rollers are arranged in three directions every 120 degrees, and the rolled material (aluminum alloy continuous cast bar 4) from which the surface layer portion has been cut is rolled in multiple stages to continuously roll the rolled material (aluminum alloy continuous). A rolling example for producing a cast bar 5) is shown.

<Drawing device (drawing device)>
Drawing is usually used to make a circular tolerance by aligning the diameter tolerance with a super steel die made of an aluminum extrudate.
A squeezing operation is performed in order to make the tip of the rolled product slightly narrow so as to enter the die. The splicer is
A method of forging by striking the tip of a material is generally used. After kissing, put the tip into the die, grab it from the opposite side and pull it out. This is usually performed while feeding the material (aluminum alloy continuous cast bar) at a place where the mouth-attaching machine and the drawing machine are adjacent to each other. The diameter of the drawing is 0.5m
It is enough to drop about m. At the time of drawing, mineral oil is used as the lubricating oil.
It is also possible to use a peeling die instead of a normal die. This is intended to aggressively cut the surface instead of aligning the diameter by reducing the surface of a normal drawing die. In this case, the surface shaving allowance is 0. A few mm is the limit.

<Centerless polishing equipment (centerless polishing equipment)>
The surface state can be improved by performing centerless polishing instead of drawing. As shown in FIG. 10, a workpiece (abrasive material, aluminum alloy continuous casting rod 5) is sandwiched between a grinding wheel 1101 and an adjustment wheel 1102, and the workpiece is moved while rotating the wheels 1101, 1102. Rotating on the support 1106 and polishing. If a feeding device is provided at the front and rear, it can be continuously fed, and the tip does not need to be processed.
Thereby, by selecting appropriate conditions, the roundness can be equal to or higher than that of the drawing.

<Standard cutting device>
FIG. 11 is an explanatory view showing an example of a standard cutting device.
The fixed cutting device 1201 cuts a continuously rolled material (aluminum alloy continuous cast bar 5) that is continuously rolled into a fixed length rolled material (aluminum alloy continuous cast bar) having a required length. However, the speed of the continuous rolled material (aluminum alloy continuous cast bar 5) may be changed by adjusting the rolling speed according to the casting speed or by roller sliding during rolling, and the speed of the continuous rolled material is not necessarily constant. Therefore, the cutting length may vary when cutting is performed at regular time intervals. For this reason, it is preferable to set the cutting timing while always measuring the actual feed amount of the continuous rolled material (aluminum alloy continuous cast bar 5) in order to accurately cut the length. The length measuring means is not limited in any way, but a length measuring roller 1202 for measuring the feed amount by bringing a roller with an encoder into contact with a continuously rolled material (aluminum alloy continuous cast bar 5) or a non-contact type laser length measuring device is exemplified. The length measuring roller 1202 can be recommended because it can accurately measure the length.

The traveling speed of the carriage at the time of cutting is preferably the same as the speed of the continuous rolled material (aluminum alloy continuous cast bar 5) before cutting. It is more preferable that the speed of the continuously rolled material is ± 5%. The traveling speed of the continuously rolled material (aluminum alloy continuous cast bar 5) can be measured by the length measuring means described above. In order to cut the continuously rolled material (aluminum alloy continuous cast bar 5) that travels, for example, as shown in FIG. 11, a cutting means may be attached to the carriage and run in synchronization with the movement of the continuously rolled material. The rolling material can be cut without delay without reducing the traveling speed. In the illustrated example, a continuous rolled material (aluminum alloy continuous cast bar 5) is sandwiched between upper and lower restraining jigs 1203a and 1203b, and a roller is attached to the lower restraining jig 1203b so that it can run. 1
The shear 1204 attached to 203a is lowered to perform cutting by shearing. Further, by restraining the continuous rolled material (aluminum alloy continuous cast bar 5), the continuous rolled material can be cut without causing problems such as bending. The driving method of the traveling unit is not limited, and examples thereof include an air cylinder, a hydraulic cylinder, an electric motor and a gear, an electric motor and a ball screw. In these driving devices, the traveling speed is controlled based on the measurement result (the traveling speed of the continuously rolled material) by the length measuring unit described above.

Moving speed of continuous rolled material (aluminum alloy continuous cast bar 5) (speed of the workpiece to be cut)
Has a width depending on various conditions, final diameter, and the like, but is higher than the moving speed of the cast material, for example, 5 m / min to 300 m / min. Specifically, when a 50 mmφ rod is rolled to 10 mmφ, the speed of the continuously rolled material (aluminum alloy continuous cast bar 5) is 25 times the inlet speed of the cast material. Even in such a continuously rolled material (aluminum alloy continuous cast bar 5) traveling at a high speed, the cutting length and the cut surface accuracy can be stabilized by performing cutting control based on actual measurement of continuous rolled material feed by the length measuring means. Can be achieved.

An example of control of the operation of the cutting carriage and cutting timing will be described.
(A) Continuously rolled material (aluminum alloy continuous casting rod 5) by a movement detector 1205 (for example, a length measuring means for detecting the amount of movement, a length measuring device, a length measuring roller, etc.) installed in front of the standard cutting device 1201. ) Is measured. The movement detector 1205 or the control device 1206 calculates the movement speed from the detected movement amount. You may use what can detect a moving speed directly with a movement detector.
(B) The control device 1206 sets the cutting timing based on the measurement result of the movement detector 1205 and the cutting length preset on the control device 1206.
(C) The carriage starts to run and accelerates until it reaches the same speed as the continuous rolled material (aluminum alloy continuous cast bar 5) so as to cut at the cutting timing set in (b).
(D) The continuous rolled material (aluminum alloy continuous cast bar 5) is clamped and cut at the set cutting timing.
(E) The continuous rolled material (aluminum alloy continuous cast bar 5) is unclamped with the end of cutting, and then the carriage is decelerated and brakes are applied as necessary.
(F) The carriage travels in the direction opposite to the traveling direction of the continuously rolled material (aluminum alloy continuous cast bar 5) in order to return to the initial position for the next cutting.
Return to (g) (b) and repeat.

Here, the cutting timing set in the control device 1206 and the movement of the carriage are the following (a) to (
Setting processing is performed as in f).
(A) The accelerating ability and acceleration curve of the bogie are investigated in advance, and the data is obtained from the control device 120.
6 is input.
(B) A cutting position for executing the cutting operation is set.
(C) The time required for the carriage to move to the cutting position is calculated from the data of (a) and (b).
(D) On the other hand, from the length measurement result and speed calculation (or measurement) result of the continuous rolled material (aluminum alloy continuous cast bar 5), it is calculated when the cut portion of the continuous rolled material reaches the cutting position.
(E) The bogie movement start time is set by calculating back the timing so that the bogie reaches the cutting position at the cutting time calculated in (d).
(F) The cutting position in (b) and the stand-by position of the carriage are adjusted so as to meet the above cycle as necessary.

Moreover, you may implement control to the cutting cart like (g)-(h) below.
(G) The speed of the carriage is controlled by monitoring whether or not the speed is the same as that of the continuously rolled material (aluminum alloy continuous cast bar 5). For example, a speed detector is mounted on the carriage to detect and monitor the speed of the continuously rolled material, and the carriage speed is controlled so that the relative speed becomes zero. Or the detector which detects a speed separately is provided in a continuous rolling material and a trolley, each speed is detected and monitored, and a trolley speed is controlled so that the difference may become zero.
(H) With the speed controlled in this way, the cutting start position is set to the following (h1) to (h
Trace and find as in 4), clamp and cut.
(H1) At the time when the movement detector detects the cutting position corresponding to the cutting length, the measurement of the speed of the continuous rolled material (aluminum alloy continuous cast bar 5) is started from that time (for example, a timer is set in the controller). ), And calculate and trace the moving position of the cutting point from the time and speed.
(H2) Or, once the cutting point is detected by the movement detector, the marking device uses a continuous rolling material (
Aluminum alloy continuous cast bar 5) Mark the surface, and on the other hand, a detector for detecting the mark is mounted on the cutting carriage, and the moving position of the cutting location is monitored.
(H3) On the other hand, once the cutting location is detected by the movement detector, the cart is started in consideration of the stand-by position and acceleration capability of the cart, and when the moving cutting location is reached, the cart and the continuous rolling material (
The carriage is accelerated so that the speed of the aluminum alloy continuous cast bar 5) is the same.
(H4) Clamping is started at the time (cutting timing) when the speed becomes the same and the cut portion is caught, and cutting is started.

The cutting means is not limited, and examples include cutting by shearing with a shear, cutting with a saw blade, and the like.
The material of these cutting means is not particularly limited, but as the shearing blade, it is possible to recommend a high-speed steel or a cemented carbide material, or a material obtained by subjecting them to a surface treatment such as TiN, TiC, TiAlN, CrN, or DLC. These materials and surface treatments are excellent in wear resistance, and the material to be cut (aluminum alloy continuous cast bar 5) is less likely to adhere and can have a long life.
Although the outer diameter and material of the saw blade are not limited, a tip saw in which a carbide tip is brazed to the blade tip portion can be recommended. With these saw blades, the cutting edge portion is less likely to wear. Moreover, it is possible to recommend high-speed steel or cemented carbide, or those obtained by subjecting them to surface treatment such as TiN, TiC, TiAlN, CrN, or DLC. These materials and surface treatments are excellent in wear resistance, and the material to be cut (aluminum alloy continuous cast bar 5) is less likely to adhere and can have a long life.
Further, the outer diameter of the saw blade may be appropriately selected according to the diameter of the material to be cut (aluminum alloy continuous cast bar 5). For example, if the material to be cut is 100 mmφ or less, a material having a diameter of 200 mm to 610 mmφ can be recommended. When the diameter of the saw blade is reduced, the outer peripheral length is shortened and the number of blades is reduced.
The life of the saw blade is shortened because the number of times of cutting of one blade is increased. On the other hand, when the diameter is increased, the rigidity of the saw blade is lowered, so that the accuracy of the cut surface is deteriorated. In addition, the number of rotations of the saw blade is 1000 rpm depending on the diameter of the saw blade. p. m-3500 r. p. m can be recommended. This is because if the rotational speed is excessively high, the cutting surface accuracy may be deteriorated due to the resonance of the saw blade itself, and if the rotational speed is excessively low, the cutting time becomes long.

The temperature of the material to be cut (aluminum alloy continuous casting rod 5) at the time of cutting is not particularly limited, but is preferably from room temperature to 300 ° C, particularly preferably from 100 ° C to 300 ° C. The cutting resistance decreases as the temperature rises. However, if the temperature is 100 ° C. or higher, the cutting resistance is significantly reduced, and the life of the cutting blade can be improved. Moreover, if it is 300 degrees C or less, it will be hard to get a damage | wound at the time of carrying out the cut regular rolling material (aluminum alloy continuous cast bar). Such temperature adjustment is performed by a rolling device 1001.
Can be carried out by adjusting the supply amount of the lubricating oil used in the above, for example, emulsion type lubricating oil, or cooling after rolling. As a cooling method after rolling, continuously rolled material (
A method of immersing or bathing the aluminum alloy continuous cast rod 5) in water, oil, or an emulsion type lubricating oil used in a rolling part can be exemplified.

Although the cut regular rolled material (aluminum alloy continuous cast bar) is discharged from the manufacturing apparatus by the carry-out device, the carry-out method is not limited at all. As a carrying-out method, the cut rolled material (
A method of dropping an aluminum alloy continuous casting rod) onto a conveyor and carrying it out, or dropping it onto a slope and rolling it out can be exemplified. It is also preferable to prevent contact between the regular rolled materials (aluminum alloy continuous cast bars) using a partition conveyor so that the surface is not damaged. Moreover, a regular rolling material (aluminum alloy continuous casting rod) can be stored directly under the regular cutting device 1201 and can be carried out collectively.

Moreover, a support means can also be provided on the side of the cut product (fixed rolled material, aluminum alloy continuous cast bar) of the continuous rolled material (aluminum alloy continuous cast bar). The support means only needs to be capable of stably supporting at least a workpiece to be moved at high speed during cutting. For example, the cutting carriage is provided with a support clamp, or the cutting carriage and the support clamping carriage are separated. The thing connected so that it is possible can be mentioned. The support means, after cutting, may be transported as it is in some cases, then releases the cut product and delivers the cut product to the next step. The next process can be a conveyor, a loading table, an articulated robot, or the like.

<< Description of other devices and processes >>
<Melting and holding furnace → continuous casting device → synchronized cutting device → peeling device → heat treatment device (homo, homogenization) → rolling device>
The peeling process can also be performed (processed) before the heat treatment process. In that case, it is preferable that the heat treatment step is performed once, since the heat treatment for homogenization and the heat treatment before rolling can be performed together, and the steps can be omitted.

<When rolling to irregular shape>
Another shape of the rolled material in the present invention will be described.
When rolling bars, rolling to a non-continuous surface where the shape of the cross section perpendicular to the longitudinal direction changes in the longitudinal direction makes it possible to continuously produce the final product shape or near-net-shaped deformed material. An example of the rolling apparatus to be used will be described.

In FIG. 12, a rolling device 1001 has at least one rolling stand 1021 that includes a plurality of rolling rollers 1022 for forming a non-continuous cross section.
The rolling stand 1021 has three rolling rollers 1022 arranged every 120 degrees and rolled from three directions. Further, as shown in FIG. 13, each rolling roller 1022 is a roller in which the distance from the rotation shaft 1026 to the circumferential surface changes in the circumferential direction in the cross section of the roller main body portion 1023. Aluminum alloy continuous casting rod 4)
A small-diameter forming portion 1023a that rolls the cast material to a small diameter and a large-diameter forming portion 1023b that rolls the cast material to a large diameter with a small distance are formed. And by the rotation of the rolling roller 1022,
The small diameter forming portion 1023a and the large diameter forming portion 1023b are alternately in contact with the cast material (aluminum alloy continuous cast bar 4), and the cast material is rolled to transfer these shapes. FIG. 12A shows a state where the large-diameter forming portion 1023b rolls the cast material (aluminum alloy continuous casting rod 4), and FIG. 12B shows a state where the small-diameter forming portion 1023a rolls the cast material. By this rolling, FIG.
As shown in FIG. 4, the large-diameter portions 51 and the small-diameter portions 52 are alternately and continuously formed into an infinitely long deformed material (aluminum alloy continuous cast bar 5A) having a discontinuous cross section. In FIG. 12, 1
Reference numeral 024 denotes flange portions provided at both ends of the roller main body 1023 in the rotation axis direction.

Further, before forming into a discontinuous cross section, the rolling roller 10 having a circular cross section as shown in FIG.
A rolling stand 1031 having 32 can be arranged and reduced in diameter and rolled into a continuous cross section. In particular, when the cast material (aluminum alloy continuous casting rod 4) is trapezoidal or pentagonal, it is better to form it into a shape close to the final cross-sectional shape before rolling to a non-continuous cross section (aluminum alloy continuous casting). It becomes easy to ensure the correctness of the shape of the rod.
In FIG. 15, reference numeral 1036 denotes the rotation axis of the rolling roller 1032.

The rolling to the continuous cross section and the rolling to the non-continuous cross section described above are both performed by a set of rolling rollers, and a plurality of rolling stands are installed and formed in multiple stages using a plurality of sets of rolling rollers. Can do. The illustrated rolling apparatus includes three rolling stands 1031 for forming a continuous section and one rolling stand 1021 for forming a non-continuous section. It is also optional to dispose two or more rolling stands 1021 for forming a non-continuous cross section, and it is also optional to perform only rolling to a non-continuous cross section without rolling to a continuous cross section. Moreover, it is not necessary to drive all of these rolling rollers, and there is no problem if the material is caught in the rolling rollers by the driving force of the preceding and following rolling rollers.

Moreover, the number of rolling rollers which comprise one rolling stand is not limited, A discontinuous cross-sectional shape can also be set arbitrarily. The rolling stand 1041 illustrated in FIG.
The roller main body portion 1043 has a small-diameter molding portion 1043a and a large-diameter molding portion 1043b, and a projection 1043c protruding outward is formed at the center in the circumferential direction of the small-diameter molding portion 1043a. Has been. When rolled using the rolling roller 1042, the deformed material (aluminum alloy continuous cast bar 5B) shown in FIG.
4 and the constriction 55 having a reduced diameter is formed at the center of the small diameter portion 54.
In FIG. 16 or FIG. 17, 1044 is a flange portion provided at both ends of the roller main body portion 1043 in the rotation axis direction, and 1046 is a rotation shaft of the rolling roller 1042.

The rolling rollers 1022, 1032, and 1042 shown above are symmetrical in shape, but the rolling rollers 1022, 1032, and 1042 may be asymmetric rolling materials by combining rolling rollers having different shapes.
Further, when rolling to a non-continuous cross section, it is not always necessary to deform the cast material (aluminum alloy continuous cast rod 4) around the entire circumference of the rolling roller. The cast material is deformed at a part of the circumference and cast at the other part. It is also possible to travel without deforming the material. For example, FIG. 12, FIG.
15 is used, the rolling roller 103 for continuous section forming in FIG. 15 is used.
2, the cast material (aluminum alloy continuous cast bar 4) is reduced in diameter to the diameter of the large diameter part 51 and formed into a round bar having a continuous cross section, and then the small diameter molded part is formed by a rolling roller 1022 for non-continuous cross section forming. 1
The shape of 023a is transferred to reduce the diameter, and the small diameter portion 52 is formed. At this time, the rolling roller 102
The second large-diameter molded portion 1023b functions as a feed roller without reducing the diameter of the cast material. Since the large-diameter forming portion 1023b does not reduce the diameter of the cast material (aluminum alloy continuous cast rod 4), it is not always necessary to contact the cast material. However, due to the material flow from the small-diameter molded portion 1023a, the diameter may be increased at and near the boundary between the small-diameter molded portion 1023a and the large-diameter molded portion 1023b. In order to prevent such a phenomenon, the large-diameter molded portion 1023b
Even when the diameter is not reduced, the large-diameter forming portion 1023b is a cast material (aluminum alloy continuous cast bar 4).
It is preferable to design the large-diameter molded portion 1023b so as to come into contact with and to restrain the cast material with the large-diameter molded portion 1023b.
In addition, the shape of the rolling surface of the rolling roller 1022 is preferably a shape that can obtain a volume balance in consideration of the flow of the material in the forming process. For example, the recessed part and / or convex part for forming the surplus part for volume balance adjustment can be provided in the rolling surface corresponding to the joint location of a molded article.

As an example of the present invention, a 50 mmφ horizontal continuous cast product cast at a cooling rate of 5 ° C./sec with the composition shown in Table 1 is homogenized at 490 ° C. × 3 hr, peeled to 48 mm φ, cut to a length of 1 m, predetermined (No. 1, 4, 8). The rolling mill was a seven-stage rolling with a three-way roller and a rolling rate of 15% to 25% for each stage. 50mmφ 1mm surface
After peeling, it was finally rolled to 20.5 mmφ, so the rolling reduction was 82%.
The rolled product was 20.5 mmφ, and was subsequently drawn to 20.0 mmφ using a drawing die. A part of the drawn material obtained was cut, heated to 400 ° C., supported at 2 points, and 9 at the center.
It was pushed and bent at 0 degrees. At this time, the presence or absence of cracks in the bent part (◯: no crack, x: cracked) was observed. Separately, a part of the test piece was cut for a tensile test, heat-treated at 495 ° C. × 2 hr, cooled with water, and subjected to aging at 170 ° C. × 8 hr (solution treatment). Thereafter, a part of the end face cut for the tensile test was taken, and the cross-sectional macrostructure was visually observed. The entire surface was fine granular crystals of 1 mm or less. Then, it processed into the test piece for tension tests, and tested.

Further, the drawn material is separately sawn to a thickness of 20 mm (length in the longitudinal direction) and 370 ° C. × 4
After the heat treatment of hr, annealing heat treatment was performed by cooling in the furnace as it was, and the cross-sectional hardness and roundness were measured. Furthermore, the upsetting rate was changed and the upsetting was performed at room temperature in the longitudinal direction, and a compression test was performed as an example of forging. The upsetting rate when a crack was seen on the side of the upset product was measured, and the upsetting rate was used to facilitate cold forging.
here,

It was. After upsetting, the cross-sectional shape was observed to determine whether a sufficient circular shape was obtained.

As a comparative example, a billet of 200 mmφ was cast, homogenized, and extruded into a hand 20.5 mmφ rod using a four-hole extrusion die. Using a drawing die, 2
Pulled out to 0.0 mmφ. The obtained bar was tested in the same manner as above (No. 2, 5, 9
). After the same T6 treatment (solution treatment) as before, a part of the end face cut for the tensile test was taken, and the cross-sectional macrostructure was visually observed, but a large number of coarse recrystallized crystals of several mm were observed.
At the same time, as another comparative example, obtained by casting and rolling with a Properti continuous rolling mill, 20.
A bar of 5 mmφ was obtained. Thereafter, it was drawn to 20.0 mmφ with a drawing die, and the same test as above was performed (No. 3, 6, 10). In the inspection after the T6 treatment (solution treatment) as before, the cross-sectional macrostructure was a structure in which coarse crystal grains of several mm and granular crystals of 1 mm or less were mixed.
Furthermore, as another comparative example, a horizontal continuous casting product of 50 mmφ is homogenized and then 20.5 mm.
Face removal was performed with a peeling machine up to φ, and a 20.0 mmφ bar was obtained by cutting. This was processed into the same test material and tested in the same manner as described above (No. 7, 11). This is a T6 process (
Solution treatment), and the cross-sectional macrostructure was visually observed.
It was a structure mixed with coarse granular crystals.

As a result, the alloy rod of the present invention has a low hardness after annealing and a high upsetting rate, so the deformability during cold forging is good, Compared to T6
Excellent tensile test characteristics after treatment. Furthermore, since the characteristics are not inferior due to hot bending, it can be seen that the material can be used for hot forging without any problems.

1 Molten aluminum alloy
2-5B Aluminum alloy continuous casting rod 51 Large diameter portion 52 Small diameter portion 53 Large diameter portion 54 Small diameter portion 55 Constriction 202 Tundish 203 Opening 204 Refractory plate-like body 205 Pouring hole 301 Horizontal continuous casting device 302 Mold 303 Gas supply Road 304 Lubricating oil supply path 305 Cooling water supply path 306 Guide roller 307 Pinch roller 401 Synchronized cutting device 402 Synchronized clamp mechanism 403 Drive mechanism 404 Support roller 405 Moving stand 406A Rail 406B Rail 407A Motor 407B Motor 408A Cutting machine 408B Cutting machine 409 Mount clamp mechanism 410 Drive mechanism 411 Length detector 601 Perimeter removal device 611 Conveying roller 616 Cutting blade 617 Support roller 618 Support roller 701 Straightening device 702 Roller pair 703 Concave roller 704 Convex roller 1001 Rolling apparatus 1011A Rolling stand 1011B Rolling stand 1012A Rolling roller 1012B Rolling roller 1014A Collar portion 1014B Collar portion 1016A Rotating shaft 1016B Rotating shaft 1021 Rolling stand 1022 Rolling roller 1023 Roller body portion 1023a Small diameter forming portion 1023b Collar portion 1026 Rotating shaft 1031 Rolling stand 1032 Rolling roller 1036 Rotating shaft 1041 Rolling stand 1042 Rolling roller 1043 Roller body portion 1043a Small diameter forming portion 1043b Large diameter forming portion 1043c Projection 1044 Brim portion 1046 Rotating shaft 1101 Grinding wheel 1102 Adjusting grindstone 1106 1201 Standard cutting device 1202 Measuring roller 1203a Upper restraining jig 1203b Lower restraining jig 204 Shah 1205 motion detector 1206 controller α roll angle

Claims (1)

8 mass% to 12 mass% of Si, 2 mass% to 5 mass% of Cu, 0.2 mass% to 1.0 mass% of Mg, 0.2 mass% to 0.4 mass% of Fe, and An alloy having a composition containing 0.2% by mass to 0.4% by mass of Mn and the balance being inevitable impurities and aluminum, with a cooling rate of 1 ° C./sec to 15 ° C./sec and a diameter of 100 mmφ or less Horizontal continuous casting process;
A step of performing a heat treatment before rolling that is held at 400 ° C. to 490 ° C. for 1 hour or more performed as a substitute for the homogenization heat treatment under the conditions of 470 ° C. to 495 ° C. for 1 hour to 5 hours, or
A step of surface chamfering or surface polishing after heat treatment before rolling;
Including a step of rolling multiple times at a rolling rate of 5% to 30%, with a rolling reduction of 75% or more,
Producing aluminum alloy rods of 20.0 mmφ or less,
A method for producing an aluminum alloy rod characterized by the above.

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