JPS61113752A - Manufacturing method of high-strength aluminum alloy material - Google Patents

Abstract

PURPOSE:To reduce unevenness of the mechanical characteristics of products among lots by subjecting an Al alloy material to be heat treated to soln. heat treatment and hardening, working it to produce a strain, and cold working the material. CONSTITUTION:An Al alloy material to be heat treated is subjected to soln. heat treatment and hardening, and it is worked at once with a tension leveler or the like to produce >=2% strain. The material is allowed to stand for an arbitrary time, cold worked at >=20% working rate, and age-hardened. By this method, unevenness of various characteristics of the alloy material after the cold working due to difference in the period in which the material is allowed to stand before the cold working is reduced or eliminated. Accordingly, a high strength Al alloy material of stable quality is obtd.

Description

Detailed Description of the Invention: fi+ Industrial Field of Application The present invention relates to a method for producing a high-strength aluminum alloy material, and more specifically, a method for producing a high-strength aluminum alloy material from a heat-treated aluminum alloy material in a stable manner. This relates to a method of manufacturing.

(2) Prior art and its problems High-strength aluminum alloy materials are produced by applying hot plastic working to heat-treated aluminum alloy ingots in the form of slabs and billets to obtain raw materials such as plates, rods, pipes, and shapes. After that, it is manufactured by combining heat treatment, age hardening, and cold working.

As the alloy type of this type of alloy material, At-Cu type 200
Various standard alloys represented by the 0 series alloy series, the ^t-Mg-8L series 6000 series alloy series, and the Mut-Zn-Mg series 7000 series alloy series, as well as manufacturers with properties equivalent to these. There are special alloys.

Furthermore.

3004 alloy and 3005 alloy among At-Mn alloys.

3105 alloy or 508 in kt-, -Kg alloy
Alloys such as 2 alloy and 5182 alloy can also be subjected to processing heat treatment due to the presence of Cu, 81, etc. as additive elements or impurities. The present invention is applicable to any of these alloy types, and these are collectively referred to as the "present alloy" hereinafter.
That's what it means.

The refining conditions for the material made of this alloy include JI8 standard HOOO1
There are various treatments such as "s +" 54 Tor" and t6 stipulated in No. 52-105509, Japanese Patent Application Laid-Open No. 57-149459, etc., but in these prior art, when T, treatment and tempering conditions that are suitable for T, treatment are applied, the process from solution treatment to cold working is When there is a standing period before the transition to It is known that the temperature changes depending on the length of the period of neglect.

In other words, if the storage period differs for each lot,
Even if the cold working rate is the same, there will be variations in the strength etc. of the two alloy materials in their final state.

It can be said that it is difficult to stably obtain products of the same quality.

For this reason, various countermeasures have been taken in conventional operations, but there are the following problems.

■ If the above-mentioned method of managing the storage period so that it is always constant, production management is complicated and productivity improvement is hindered.

(2) The method of leaving the product for a sufficient period of time (4 to 5 days) until the GP zone has grown sufficiently and no change in strength is observed increases the amount of work in progress, lengthens the number of production days, and deteriorates productivity.

■ It is possible to perform low-temperature aging treatment between solution treatment and cold working to accelerate the growth of the GP zone and stabilize the properties at an early stage, but this increases the production cost because the number of production steps increases.

(3) Purpose of the invention To reduce the lot-to-lot variation in mechanical properties of the final product, the alloy material, which is caused by the growth of GP and zones during the standing period from deep burying to cold working. With the aim of obtaining an alloy material of stable quality, the inventors of the present invention conducted solution treatment and quenching as a means of suppressing the growth of the GP zone.

We have shown that this problem can be solved by immediately introducing a processing process that introduces a strain of 2% or more.

(4) Structure of the invention ゛'The present invention involves subjecting an ingot such as a slab or billet to hot plastic working such as hot rolling or hot extrusion, and if desired, subsequent cold working such as rolling multiple drawing. Immediately after solution treatment and quenching (hereinafter referred to as "as soon as possible") of the formed material made of this alloy obtained by carrying out This method is characterized by obtaining an alloy material.

Strain introduction processing can be performed as quickly as possible by using a processing method that is directly connected to the quenching device. As usual, artificial aging treatment can be performed after cold working to further improve the strength. ' The following will be explained based on embodiments.

a) In the case of rolled raw material If the raw material is a plate-shaped material, it is heated at 400 to 63O
The slab-shaped main alloy ingot that has been homogenized for 8 hours is hot-rolled to the desired thickness at a rolling start temperature of 400 to 600°C and a rolling end temperature of 200 to 450°C. Then, if desired, further cold rolling is performed.

Subsequently, it is subjected to a solution treatment held at 400 to 620°C for within 3 hours, and then rapidly cooled.

The quenching treatment is carried out by immersion in oil in water or the like, or by forced air cooling. In this case, the cooling rate is desirably 100° C./min or more. Immediately after cooling, the strain introduction process is carried out using a tension leveler or roller m-shaler, which is usually used as a means for straightening and straightening plate-shaped objects.

This can be done by one or more of the following methods, such as a skin bath and a stretcher.

This is done so that the amount of distortion is 2% or more.

Here is the amount of distortion.

The amount of distortion is 2% or more.

By performing processing to introduce a strain amount of preferably 3 to 7%, the effect of suppressing the growth of the GP zone can be appropriately expressed.

In this case, when the amount of distortion is 2% or less.

Only the effect of removing quenching strain is expressed, and the effect of suppressing the growth of the GP zone is insufficient.Although the amount of machining strain needs to be 2% or more, the effect of suppressing the growth of the CP zone is improved even if the amount of strain is 10 or more. It is not practical because there is no economic benefit. Therefore, in practice, the amount of distortion is appropriately selected within the range of 2 to 10%, depending on the capacity of the machine used and the tolerance of quality variation Φ required for the alloy material.

Conventionally, straightening processing has been performed following quenching after solution treatment, but this is for the purpose of correcting deformation distortion (becoming wavy) due to quenching and removing residual stress. It gives a distorted view of about 1%, and even at this level - it is not possible to exhibit the effect of suppressing GP Sole growth.

In this way, the strain-introducing processing of the present invention can simply increase the processing degree mechanically without requiring the addition of new equipment on the upper side of the manufacturing equipment, if a tension leveler or the like is conventionally used in the process. It can be implemented by simply adjusting. This is good.

The effect of straightening after quenching and the effect of inhibiting GP zone growth are simultaneously expressed.

After the strain introduction process, after an arbitrary standing period, cold rolling is performed at a working rate of 2'O% or more in order to increase the strength by work hardening. If the working rate is less than 20 inches, no improvement in strength due to active work hardening can be expected, and a working rate of 25 to 80% is usually practical, and if it is more than 80 inches, cracks may occur due to work hardening. I don't like it because it increases.

In this case, further strength can be added depending on the product application.
:1 When required, etc., K is a method of dividing cold rolling into two times and performing an intermediate aging treatment in which the temperature is maintained at 100 to 200°C for 2 hours, for example, or a final aging treatment of 100 to 280°C after cold rolling. A method of holding at ℃ for 5 hours or less may be used in combination.

By going through the above steps, the growth of the GP zone during the standing period between solution treatment and cold rolling is suppressed, the degree of age hardening of the formed material remains at a higher level, and the subsequent Because the work hardening C due to cold rolling remains at a constant level, the properties of the final alloy material (in this case, a plate) are uniform even if the lot differs, such as one can stock or automobile parts ( For example, it will be possible to provide products for body seats, wheels) with a high yield.

b) In the case of an extruded material When the material is an extruded material, two main embodiments can be adopted since the extrusion means can exhibit a solution treatment effect.

That is, as a first form, a hollow or solid billet ingot made of this alloy is subjected to a homogenization treatment at 400 to 630°C for 2 to 48 hours, kept at room temperature, and then extruded at a temperature of 400°C.
Method of preheating to ~500℃ and extrusion processing, or method of extrusion processing at ~500℃
After homogenization treatment at 640°C for 2-10 hours.

The product is cooled to the extrusion temperature and immediately extruded to obtain a desired shape, and the die end is quenched in the usual manner. 'The extrusion processing method in this case is the direct extrusion □ method.

Needless to say, either indirect extrusion or continuous extrusion may be used.

Next, the stretcher is immediately subjected to a strain-introducing process of 2% or more, and after an arbitrary standing period, cold working is performed at a working rate of 20% or more by means such as forging or drawing.

The present alloy material having the final desired shape is obtained. At this time, if desired, following the cold working, an artificial aging treatment in which the material is held at 100 to 250°C for 1 to 10 hours is performed.

In a second embodiment, which is carried out when the raw material is a bar-shaped body, cold working such as drawing is performed after the same embossing process as described above is performed. Subsequently, as the next step, solution treatment is carried out at 400 to 600°C for up to 3 hours, quenching is performed by forced air cooling with a fan, water spray, etc., and immediately more than 2 lines of strain are introduced on a stretcher. Thereafter, after an arbitrary standing period, cold working is performed by forging and drawing at a working rate of 20 inches or more to obtain an alloy material in a desired shape.

In two embodiments of such extruded material. The effect of the amount of strain introduced in the strain introduction process and the processing rate of cold working on the properties of the alloy material is the same as that described for the rolled material.

The present alloy material obtained from these extruded materials is 2, for example,
It can exhibit excellent properties for various applications such as ring roll materials, forged materials for bicycles, and dampers for automobiles.

As described above, one aspect of the present invention is to apply solution treatment to a heat-treated aluminum alloy formed material obtained by hot plastic working, although various embodiments may be adopted depending on the shape of the formed material. Immediately after the hardening process, strain introduction processing of 2 or more inches is performed.

It is characterized by performing cold working at a processing rate of 20 inches or more after an arbitrary standing period, and after that, age hardening treatment by artificial aging may be carried out as appropriate, regardless of natural aging. be.

(5) Examples The present invention will now be specifically described with reference to examples, but the invention is not limited thereto.

Example 1 Adult 6009 equivalent aluminum alloy (MnQ.

729, 810.62%, Mg(L61%,
F@Q, 40%, Cuα21%, Zn0.01%+T
' O-021 + remainder At, all values are weight %.
ls9 o"cfo" 1m, l"l, i poor treatment 9 then rolling start temperature 550°C.

After hot rolling at a rolling finish temperature of 380°C,
Through cold rolling at a processing rate of 88%, a coiled material for can stock having a plate thickness of 0.8 mm was obtained.

Using a continuous solution treatment furnace, 55
Solution treatment is performed at 0°C for 1 minute, followed by water quenching, cooling to room temperature, and strain introduction using a tension leveler connected to the quenching tank to give the amount of strain introduced as shown in Table 1. Processed. Next, after being left at room temperature for a predetermined time (Table 1 shows the elapsed time from the completion of quenching), it was cold rolled to a plate thickness of 0.34 vmt (processing rate of 57
(equivalent to %). Table 1 shows the results of measuring the properties of the plate material thus obtained.

Table 1 (however, σ8 is tensile strength kP/+j), σ, 2
is the 0.2 inch proof stress (ky/mj), and δ is the elongation (chi).

(The same applies hereafter) Next, in order to further improve the strength and toughness of each treated material, 9
As an aging treatment, a heat holding treatment was performed at 205° C. for 10 minutes.

The results are shown in Table 2.

Table 2 From the results in Tables 1 and 2, according to the present invention, by performing strain introduction processing with a strain introduction amount of 2 inches or more,
It can be seen that the effect of inhibiting the growth of cpcy/ is expressed, the influence of the length of the left period is eliminated, and the management of the left period can be made unnecessary. Furthermore, it can be seen that when the application requires even higher strength and toughness, aging treatment may be performed after cold working.

Example 2 J I lit 7NO1 alloy (Zn437%, ME
j, 72%, Mn0.52%, P"@0.20%,
SI 0.11%.

A slab of 0.02% Cu, 02% TiO, balance A/) was subjected to homogenization treatment at 480°C for 12 hours, hot rolled at a rolling start temperature of 460°C to form a 10m thick plate, and then cooled. A plate with a thickness of 6 mm was produced by inter-rolling.

Next, after solution treatment at 450° C. for a minute with SO, water quenching, cooling to room temperature, and immediately strain introduction processing using a skin pass roll was performed to give a predetermined amount of strain introduction. After that, after leaving it at room temperature for a predetermined period of time, a thickness of 40 mm was formed using a rolling method with a processing rate of 33 mm.
I made a simple wheel.

Table 3 shows the results of characteristic tests conducted on the manufactured wheels.

The results in Table 5 also show that by employing strain-introducing processing, it is possible to obtain this alloy material with less variation in mechanical properties without having to control the standing period before cold working. .

Example 3 JIi92017 equivalent alloy (Cu3.96%, Mn09
74%, MfO, 63chi, S10.5a, F・0.2
7%, remainder AZ) extruded tube (outer diameter 5 (wall thickness 4 at 1 m,
Otm) was subjected to solution treatment at 510°C for 1 hour and water quenched.

Next, a predetermined strain introduction process was performed using a stretcher, and the material was left at room temperature for a predetermined period of time.

Cold drawing with a working degree of 40%, wall thickness 24w1
A drawn pipe with an outer diameter of 48 m+ was manufactured.

The Vickers hardness of the pipe was measured.

The results shown in Table 4 were obtained for each condition.

The present results in Table 4 also show that the strain introduction process can reduce variations in the properties of the alloy material due to differences in the standing period.

(6) Is it possible to reduce the occurrence of variations in the properties of the alloy material after cold working due to differences in the standing period before cold working by adding strain introduction processing immediately after the effect of the invention? It can be prevented.

This is presumed to be due to the fact that strain introduction processing reduces the amount of excess pores due to quenching and suppresses the growth of the GP zone.

The effects of the present invention can be summarized as follows.

■Eliminating the hassle of managing storage periods in on-site operations where storage periods often differ for each lot.

(2) Even if the standing period is different, the quality level of the alloy material manufactured by cold working is stable22, so the yield can be improved by 1.

■Therefore, the quality of the alloy material obtained through the subsequent artificial aging treatment is also stable.

Any high-strength alloy material can be stably obtained.

etc., the present invention is extremely useful industrially.

Claims (1)

[Claims] After the heat-treated aluminum alloy material is solution-treated and quenched, it is immediately processed to introduce a strain of 2% or more, and after being left for an arbitrary period of time, it is cold-worked at a processing rate of 20% or more. A method for producing high-strength aluminum alloy material.