CN115074616A - Hot-dip aluminum-zinc steel plate for refrigerator bottom plate and manufacturing method thereof - Google Patents
Hot-dip aluminum-zinc steel plate for refrigerator bottom plate and manufacturing method thereof Download PDFInfo
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips of ferrous alloys
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0226—Hot rolling
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0236—Cold rolling
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- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
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- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
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- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
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- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
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- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
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- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
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- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
- C23C2/04—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor characterised by the coating material
- C23C2/12—Aluminium or alloys based thereon
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/005—Ferrite
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Abstract
The invention discloses a hot-dip aluminum-zinc plated steel plate for a refrigerator bottom plate and a manufacturing method thereof, and mainly solves the technical problems of high production cost, poor stamping performance and in-furnace hot buckling during annealing production by a horizontal continuous annealing furnace of the existing cold-rolled hot-dip aluminum-zinc plated steel plate for the refrigerator bottom plate with the thickness of 0.20-0.28 mm. The technical scheme is that the hot-dip aluminum-zinc steel plate for the bottom plate of the refrigeratorThe substrate comprises the following chemical components in percentage by weight: c: 0.0010-0.0025%, Si is less than or equal to 0.03%, Mn: 0.35-0.45%, P: 0.050% -0.070%, S is less than or equal to 0.020%, Alt: 0.020-0.050%, Ti: 0.040-0.060%, N is less than or equal to 0.0040%, and the balance is Fe and inevitable impurity elements; yield strength R of hot-dip aluminum-zinc steel plate P0.2 220 to 260 MPa; the refrigerator bottom plate is used.
Description
Technical Field
The invention relates to a hot-dip aluminum-zinc steel plate, in particular to a hot-dip aluminum-zinc steel plate for a refrigerator bottom plate and a manufacturing method thereof, and specifically relates to a cold-rolled hot-dip aluminum-zinc steel plate with the thickness of 0.20-0.28 mm and the yield strength of 220MPa, belonging to the technical field of iron-based alloy and cold-rolled continuous hot-dip aluminum-zinc steel plates.
Background
The hot-dip aluminum-zinc coating steel plate is widely applied to the fields of building industry, household appliance industry, industrial instrument industry, electrical cabinets, packaging industry and the like due to excellent corrosion resistance, coating property, processability and economy. Compared with pure zinc steel plates, the corrosion resistance of the zinc-plated steel plate is better, and particularly when the zinc-plated steel plate is applied to the household appliance industry, a plating layer thinner than pure zinc can be adopted to obtain better corrosion resistance, so that the manufacturing cost of the household appliance is reduced.
The cold-rolled hot-dipped aluminum-zinc steel plate with the thickness of 0.20-0.28 mm is commonly used for refrigerator bottom plates in recent years, and has the use characteristics that: shearing a cold-rolled hot-dip aluminum-zinc plated steel plate with the width of 700-1200 mm and coated with a fingerprint-resistant film into a proper size through a plate, and punching by an upper punching machine set; the refrigerator bottom plate has a specific shape, the convex hull is most easily punched and cracked, the height of the highest convex hull is 22mm, the finally formed refrigerator bottom plate cannot be punched and cracked, and then the refrigerator bottom plate is assembled with other parts, and a foaming agent is injected to finally produce a finished refrigerator product. In order to meet the function of bearing foaming agent, the aluminum-plated zinc plate is not allowed to have stamping cracking after being stamped and formed.
The Chinese patent application with the application publication number of CN1542158A discloses a hot-dip aluminum-zinc alloy steel plate and a manufacturing method thereof, mainly comprising the manufacturing method of the aluminum-zinc alloy steel plate, which is not specific to specific specifications and purposes, has the production speed of 30-120 m/min, too low speed and high production cost, and is not suitable for the production of aluminum-zinc alloy.
The application publication No. CN101352946A discloses a hot-dip aluminum-zinc plated steel plate/strip for deep drawing and a production method thereof, mainly comprising a hot-dip aluminum-zinc plated steel plate/strip for deep drawing and a production method thereof, wherein the yield strength of the product is 140-220 MPa, and the product cannot meet the requirement of the strength of a bottom plate of a refrigerator.
The Chinese patent application publication No. CN103320689A discloses a hot-dip aluminum-zinc deep-drawing steel with thickness greater than 1.2mm and a manufacturing method thereof, and mainly comprises an aluminum-zinc deep-drawing steel with thickness greater than 1.2mm and a manufacturing method thereof, which can not meet the thickness requirement of a bottom plate of a refrigerator.
The application publication No. CN105970105A discloses a hot-dip aluminum-zinc plate/belt for ultra-deep drawing and a preparation method thereof, mainly comprising the hot-dip aluminum-zinc plate/belt and the preparation method thereof, wherein the yield strength of the product is 130-190 MPa, and the requirement of the refrigerator bottom plate strength cannot be met.
The application publication No. CN108103429A discloses a production method of a hot-dip aluminum-zinc silicon steel plate, which mainly comprises a production method of a hot-dip aluminum-zinc silicon steel plate, wherein the yield strength of the product is 140-220 MPa, and the requirement of the strength of a bottom plate of a refrigerator cannot be met.
The application publication No. CN109332615A discloses a hot-dip aluminum-zinc plated steel plate/strip and a production method thereof, mainly comprising a low-cost hot-dip aluminum-zinc plated steel plate/strip and a production method thereof, wherein the thickness of the hot-dip aluminum-zinc plated steel plate/strip is 0.8-2.0 mm, and the requirement of the thickness of a bottom plate of a refrigerator can not be met.
The application publication No. CN107904490A discloses a thin hot-dip aluminum-zinc alloy steel plate for a structure and a preparation method thereof, and mainly comprises the thin hot-dip aluminum-zinc alloy steel plate for the structure and the preparation method thereof, wherein the chemical component C of the steel plate is 0.05-0.12 percent, and the steel plate cannot meet the requirement of the strength of a bottom plate of a refrigerator.
The application publication number is CN103510002A, and the Chinese patent application document mainly comprises a gapless atomic cold-rolled hot-dip galvanized steel sheet and a production method thereof, wherein the thickness of the gapless atomic cold-rolled hot-dip galvanized steel sheet is 0.3-1.2 mm, the yield strength is 165-200 MPa, and the requirements of the thickness and the strength of a steel sheet at the bottom of a refrigerator cannot be met.
The application publication number is CN106854729A, and the Chinese patent application document mainly comprises a phosphorus-containing interstitial free cold-rolled galvanized steel sheet and a manufacturing method thereof, wherein the thickness of the phosphorus-containing interstitial free cold-rolled galvanized steel sheet is 0.3-0.8 mm, the yield strength is 260-300 MPa, and the requirements of the thickness and the strength of a bottom steel sheet of a refrigerator cannot be met.
The cold-rolled hot-dip aluminum-zinc plated steel plate with the thickness of 0.20-0.28 mm is extremely thin, so that the strength of the steel plate is too low in the production process; the rolled hard strip steel after cold rolling is annealed in a horizontal continuous annealing furnace, the thermal buckling in the furnace can be generated in the annealing process, the requirement of continuous production cannot be met, and the production cost is overhigh.
In the process of manufacturing the refrigerator bottom plate by stamping, the cold-rolled hot-dip aluminum-zinc plated steel plate is easy to be stamped and cracked in the stamping process because the highest convex hull height of the refrigerator bottom plate is 22mm, so that the stamping processing requirement of the refrigerator bottom plate cannot be met, the qualification rate of the refrigerator bottom plate is low, and the production cost is high.
Disclosure of Invention
The invention aims to provide a hot-dip aluminum-zinc steel plate for a refrigerator bottom plate and a manufacturing method thereof, and mainly solves the technical problems of high production cost, poor stamping performance and furnace heat buckling during annealing production by a horizontal continuous annealing furnace of the conventional cold-rolled hot-dip aluminum-zinc steel plate for the refrigerator bottom plate with the thickness of 0.20-0.28 mm.
The hot-dip aluminum-zinc steel plate disclosed by the invention is punched and processed into the refrigerator bottom plate, when the highest punching height is 22mm, the hot-dip aluminum-zinc steel plate cannot crack, the punching performance of the hot-dip aluminum-zinc steel plate is good, and the punching processing requirement of the refrigerator bottom plate is met.
The invention adopts the technical scheme that the hot-dip aluminum-zinc steel plate for the refrigerator bottom plate comprises the following chemical components in percentage by weight: c: 0.0010-0.0025%, Si is less than or equal to 0.03%, Mn: 0.35-0.45%, P: 0.050% -0.070%, S is less than or equal to 0.020%, Alt: 0.020-0.050%, Ti: 0.040-0.060 percent, less than or equal to 0.0040 percent of N, and the balance of Fe and inevitable impurity elements.
The metallographic structure of the hot-dip aluminum-zinc steel plate is ferrite, the grain size grade of the ferrite structure is I9-11 grade, and the yield strength R of the hot-dip aluminum-zinc steel plate with the thickness of 0.20-0.28 mm P0.2 220 to 260MPa, tensile strength R m 340-420 MPa, elongation after break A 80mm 25 to 38 percent, 1The bending test at 80 degrees shows that d is 0 a; the thickness of the fingerprint-resistant film of the hot-dip aluminum-zinc plated steel plate is 0.8-1.4 g/m 2 The dynamic friction coefficient of the fingerprint-resistant film is 0.10-0.20.
The dynamic friction coefficient of the invention is the ratio between the friction force and the positive pressure when objects in contact with each other do relative motion.
The reason why the chemical composition of the substrate of the hot-dip aluminized zinc steel sheet for a refrigerator bottom plate according to the present invention is limited to the above range is as follows:
carbon: the content of C in the IF steel is reduced, so that excellent stamping performance is obtained, high elongation can be obtained at low annealing temperature, and the stamping performance of the material is ensured. However, too low a C content is difficult to achieve in industrial production, and significantly increases the steel-making cost. The content range of C is preferably set to be 0.0010-0.0025% in consideration of the aspects of cost and performance.
Silicon: the silicon has a large contribution degree to the strength, but the heating process of the direct-fired section of the horizontal annealing furnace is an oxidizing atmosphere, silicon elements in a steel plate are easily oxidized and are unfavorable for the binding force of an aluminum-zinc-plated coating, according to the test result, no silicon alloy is added in the production and manufacturing process, and the content of Si is designed to be 0-0.03%.
Manganese: important solid solution strengthening elements are added to ensure the comprehensive strength of steel, proper Mn is added to improve the strength of the steel plate, the mechanical property of the steel plate is considered, and the low cost requirement is also considered, wherein the Mn content control range is as follows: 0.35 to 0.45 percent.
Phosphorus: p is generally dissolved in ferrite, the strengthening effect of the P element is remarkable, and the tensile strength P has a positive linear relationship. However, with the addition of the solid solution strengthening element, the micropore forming rate during metal drawing is increased, and the elongation of the strip steel is reduced. In addition, the addition of solid solutions also causes a decrease in the n-value and r-value. According to the comprehensive balance of strength and elongation, the content of P is preferably P: 0.050% -0.070%.
Sulfur: the S in the invention is an impurity element, and the control range of the S is required to be less than or equal to 0.020% according to the actual steelmaking production capacity.
Aluminum: the aluminum element mainly plays a role in removing oxygen in the steel, avoiding the formation of non-metallic inclusions in the solidification process, and simultaneously fixing nitrogen in the steel in the form of aluminum nitride, but the excessive aluminum affects the coating adhesion of the steel. Therefore, the aluminum content is preferably 0.020% to 0.050%.
Nitrogen: n is an unavoidable impurity element, and a reduction in the nitrogen content is advantageous for the workability of the aluminum-zinc plate, and the amount of titanium alloy added can be reduced, so that a smaller amount is better. The invention sets the nitrogen content less than or equal to 0.0040 percent by integrating the steelmaking capacity.
Titanium: ti element is a strong carbon and nitride forming element, can completely fix interstitial atoms such as carbon, nitrogen and the like in steel to form interstitial-free steel so as to ensure non-timeliness and ultra-deep drawing property. Since the precipitation of Ti (C, N) is a kinetic process, in order to completely fix C, N atoms into compounds, an excess of Ti must be added, which is in the form of titanium sulfide (TiS, Ti) 4 C 2 S 2 ) In the steel, either in the form or in solid solution, but when the titanium excess is too great (. gtoreq.0.040%), the steel exhibits non-ageing properties. In combination with cost and aging performance, the invention requires that the titanium content is preferably Ti: 0.040% -0.060%.
A method for manufacturing a hot-dip aluminum-zinc steel plate for a refrigerator bottom plate comprises the following steps:
the method comprises the following steps of continuously casting molten steel to obtain a continuous casting slab, wherein the molten steel comprises the following chemical components in percentage by weight: c: 0.0010-0.0025%, Si is less than or equal to 0.03%, Mn: 0.35-0.45%, P: 0.050% -0.070%, S is less than or equal to 0.020%, Alt: 0.020-0.050%, Ti: 0.040% -0.060%, N is less than or equal to 0.0040%, and the balance is Fe and inevitable impurity elements;
heating the continuous casting plate blank to 1190-1230 ℃ by a heating furnace, and then carrying out hot rolling, wherein the hot rolling is a two-section rolling process, the rough rolling is 5-pass continuous rolling, and the finish temperature of the rough rolling is 1040-1100 ℃; the finish rolling is 7-pass continuous rolling, and the finish rolling finishing temperature is 900-940 ℃; after finish rolling, the thickness of the steel plate is 2.3-2.8 mm, laminar cooling adopts front-section cooling, and the coiling temperature is 660-700 ℃ to obtain a hot-rolled steel coil;
hot rolled steel coil is uncoiled again, and then is subjected to acid cleaning, cold rolling, annealing by a horizontal continuous annealing furnace and hot dippingLeveling and coating a fingerprint-resistant film on the aluminum-zinc alloy, and coiling to obtain a hot-dip aluminum-zinc plated steel plate with the thickness of 0.20-0.28 mm; the cold rolling reduction rate is 90-92%; annealing the cold-rolled strip steel in a hard rolling state in a horizontal continuous annealing furnace at the annealing speed of 121-140 m/min, wherein the temperature of the strip steel in a direct-fired section of the horizontal continuous annealing furnace is 630-670 ℃, the time of the strip steel in the direct-fired section is 9.5-11.0 s, the annealing temperature of the strip steel in a soaking section of the horizontal continuous annealing furnace is 760-800 ℃, and the annealing time of the strip steel in the soaking section is 25-30 s; the leveling elongation is 0.4% -0.8%; after roller coating, baking and curing, the fingerprint-resistant film thickness of the hot-dip aluminum-zinc steel plate is 0.8-1.4 g/m 2 The dynamic friction coefficient of the fingerprint-resistant film is 0.10-0.20.
The hot rolling process adopted by the invention is based on the component system and the phase transformation point calculated by a simulation test.
The production process adopted by the invention has the following reasons:
1. setting of heating temperature of continuous casting slab
In order to ensure the dissolution of second phase particles such as AlN and Ti (C, N) in the heating process of the continuous casting slab and prevent the strip steel from being naturally cooled in the hot rolling process so as not to meet the requirement of finish rolling, higher slab heating temperature is required. However, if the heating temperature is too high, it is not favorable for the precipitation of the second phase particles in the coiling process, besides increasing the energy consumption cost, and it will increase the burden for the subsequent annealing process. In order to ensure the requirements of complete austenitization and subsequent hot working, and in consideration of economic requirements, the heating temperature is preferably set to 1190 to 1230 ℃.
2. Setting of roughing finishing temperature
The rough rolling process is controlled to be rolling above the austenite recrystallization temperature, and austenite grains in the casting blank are refined by rough rolling. If the rough rolling finishing temperature is too high, the grain refining effect is not good, and if the finishing temperature is too low, the finish rolling finishing temperature cannot be ensured. In order to facilitate the continuous processing of the subsequent finishing mill group and the control of the iron scale, the finishing temperature of rough rolling is preferably 1040-1100 ℃.
3. Setting of finish Rolling finishing temperature
In order to obtain certain strength and higher forming performanceAnd a flat steel plate, the iron scale on the surface of the hot coil is difficult to control when the finish rolling temperature is too high, and the two-phase region rolling and the edge wave formation are easy to occur when the finish rolling temperature is too low; the product is ultra-low carbon steel, Ar 3 The phase transformation point is higher, and the finishing temperature is set to be higher in order to prevent the finish rolling from rolling in a two-phase region; however, the finish rolling temperature cannot be too high from the viewpoint of refining austenite grain size and promoting coarsening of precipitates. Therefore, the finishing temperature of finish rolling is controlled to be 900-940 ℃ in comprehensive consideration.
4. Setting of laminar cooling system and hot rolling coiling temperature
The coiling temperature mainly affects the recrystallization temperature and the press formability of the material. If a lower coiling temperature is adopted, the recrystallization temperature of the material is increased, which is not beneficial to the subsequent annealing; and the coiling temperature is lower, so that the yield strength of the material is higher, the elongation is reduced, and the stamping performance of the material is not facilitated. However, if the coiling temperature is too high, a large amount of scale will be generated on the surface after coiling, which is not favorable for the subsequent pickling. Comprehensively considering, the laminar cooling adopts front-section cooling, and the coiling temperature is 660-700 ℃ to obtain the hot-rolled steel coil.
5. Setting of Cold Rolling reduction
After the hot rolled steel coil is uncoiled again and the surface iron oxide scale is washed off by acid, the hot rolled steel coil is limited by rolling capacity after being subjected to cold rolling for multiple times on a cold continuous rolling mill or a reciprocating single-stand rolling mill, the cold rolling reduction rate is 90-92%, and the cost performance is good.
6. Setting of annealing speed, annealing temperature and annealing time
In order to fully recover and recrystallize the steel plate, the steel plate is heated by a horizontal continuous annealing furnace, the strength of the steel plate is comprehensively considered, and the preferable range is as follows: in order to take the strength and the production efficiency of the strip steel into consideration, the annealing speed is preferably 121-140 m/min, the temperature of the strip steel in a direct-fired section of the horizontal continuous annealing furnace is 630-670 ℃, and the time of the strip steel in the direct-fired section is 9.5-11.0 s; the annealing temperature of the strip steel in the soaking section of the horizontal continuous annealing furnace is 760-800 ℃, and the annealing time of the strip steel in the soaking section is 25-30 s.
7. Setting of the Flat elongation
The main purpose of leveling is mainly to adjust the surface roughness; too low a flattening ratio will result in poor surface quality, too high a flattening ratio will exceed the capacity of the leveler, and preferably the flattening elongation is 0.4% to 0.8%.
8. Setting of fingerprint-resistant film thickness and fingerprint-resistant film dynamic friction coefficient
The hot-dip aluminum-zinc steel plate not only meets the foaming requirement of the bottom steel plate, the binding power between the steel plate and the foam is more than or equal to 150kPa, but also meets the requirement of no cracking during stamping; when the hot-dip aluminum-zinc steel plate is coated with the fingerprint-resistant film, if the dynamic friction coefficient is too low, the foaming performance is influenced, and if the dynamic friction coefficient is too high, the stamping cracking is caused; if the film thickness is too low, the stamping process is easy to damage, if the film thickness is too high, the cost is obviously increased, and preferably, after the hot-dip aluminum-zinc steel plate is cured by roller coating and baking, the fingerprint-resistant film thickness of the hot-dip aluminum-zinc steel plate is 0.8-1.4 g/m 2 The dynamic friction coefficient of the fingerprint-resistant film is 0.10-0.20.
The metallographic structure of the hot-dip aluminum-zinc steel plate produced by the method is ferrite, the grain size grade of the ferrite structure is I9-11 grade, and the yield strength R of the hot-dip aluminum-zinc steel plate P0.2 220 to 260MPa, tensile strength R m 340-420 MPa, elongation after break A 80mm 25-38%, and passing through a 180 DEG bending test with d being 0 a.
The hot-dip aluminum-zinc steel plate produced by the method is punched into the refrigerator bottom plate, when the highest punching height is 22mm, the hot-dip aluminum-zinc steel plate does not crack, the punching performance of the hot-dip aluminum-zinc steel plate is good, and the punching processing requirement of the refrigerator bottom plate is met.
Compared with the prior art, the invention has the following positive effects: 1. the hot-dip aluminum-zinc plated steel plate has the optimal mechanical property, namely the yield strength R of the hot-dip aluminum-zinc plated steel plate with the thickness of 0.20-0.28 mm, which is obtained by controlling reasonable components, a hot rolling process, a cold rolling process, an annealing process and an aluminum-zinc plating process P0.2 220 to 260MPa, tensile strength R m 340-420 MPa, elongation after break A 80mm 25-38%, and passing through a 180-degree bending test with d being 0 a; the dynamic friction coefficient of the fingerprint-resistant film is 0.10-0.20, and the requirements on the strength degree and the foaming of the refrigerator bottom plate are met. 2. The components of the substrate through which the hot-dip aluminum-zinc plated steel sheet of the invention passes,The annealing process and the fingerprint-resistant film dynamic friction coefficient are optimally designed, the manufacturability is strong, the production cost is low, and the manufacturing process is simple. 3. In the production process of the hot-dip aluminum-zinc coated steel plate, when the strip steel in a hard rolling state after cold rolling is annealed in the horizontal continuous annealing furnace, the buckling of the strip steel in the furnace can not occur, the requirement of continuous production is met, and the production cost is low; the cold-rolled hot-dipped aluminum-zinc steel plate is processed into the refrigerator bottom plate by stamping, when the highest stamping height is 22mm, the cold-rolled hot-dipped aluminum-zinc steel plate can not crack, the stamping performance of the cold-rolled hot-dipped aluminum-zinc steel plate is good, and the stamping processing requirement of the refrigerator bottom plate is met.
Drawings
FIG. 1 is a photograph showing a metallographic structure of a hot-dip aluminum-zinc plated steel sheet according to example 1 of the present invention.
Detailed Description
The present invention is further described with reference to examples 1 to 5, which are shown in tables 1 to 5.
Table 1 shows the chemical composition (in weight%) of the substrate of the hot-dip aluminum-zinc coated steel sheet according to the example of the present invention, and the balance Fe and inevitable impurities.
Table 1 chemical composition of substrate of hot-dip aluminum-zinc coated steel sheet of example of the present invention, unit: and (4) weight percentage.
The method comprises the steps of smelting in a converter to obtain molten steel meeting the requirement of chemical components, blowing argon and adding alloy elements to obtain the molten steel meeting the requirement of the chemical components, and continuously casting the molten steel to obtain a continuous casting slab, wherein the thickness of the continuous casting slab is 210-230 mm, the width of the continuous casting slab is 800-1250 mm, and the length of the continuous casting slab is 5000-10000 mm.
Sending the fixed-length plate blank produced in the steel-making process to a heating furnace for reheating, taking out of the furnace for dephosphorization, and sending the plate blank to a continuous hot continuous rolling mill for rolling; controlling rolling by a rough rolling mill and a finish rolling continuous rolling unit, adopting front-section cooling for laminar cooling, and then coiling to produce a hot rolled steel coil, wherein the thickness of the hot rolled steel coil is 2.3-2.8 mm; the hot rolling process control is shown in Table 2.
TABLE 2 Hot Rolling Process control parameters of the inventive examples
And (2) uncoiling the hot rolled steel coil again, carrying out acid pickling and edge cutting, carrying out cold rolling on a 5-stand cold continuous rolling mill or a reciprocating single-stand rolling mill, wherein the cold rolling reduction rate is 90-92%, annealing the steel strip in a hard rolling state after cold rolling through a horizontal continuous annealing furnace, hot-plating aluminum and zinc, flattening, coating a fingerprint-resistant film, and coiling to obtain a finished cold-rolled hot-plated aluminum and zinc steel coil with the thickness of 0.20-0.28 mm. The annealing process comprises the following steps: annealing the cold-rolled hard strip steel in a horizontal continuous annealing furnace at the annealing speed of 121-140 m/min, wherein the temperature of the strip steel in a direct-fired section of the horizontal continuous annealing furnace is 630-670 ℃, the time of the strip steel in the direct-fired section is 9.5-11 s, the annealing temperature of the strip steel in a soaking section of the horizontal continuous annealing furnace is 760-800 ℃, and the annealing time of the strip steel in the soaking section is 25-30 s; the leveling elongation is 0.4-0.8%; the thickness of the fingerprint-resistant film of the hot-dip aluminum-zinc plated steel plate is 0.8-1.4 g/m 2 The coefficient of dynamic friction of the fingerprint-resistant film is 0.10-0.20. The technological control parameters of cold rolling, annealing, flattening and roller coating of the fingerprint-resistant film are shown in table 3.
TABLE 3 control parameters of the cold rolling, annealing and leveling processes of the examples of the present invention
Referring to fig. 1, the metallographic structure of the hot-dip aluminum-zinc steel plate obtained by the method is ferrite, the grain size grade of the ferrite structure is I9-11 grade, and the yield strength R of the hot-dip aluminum-zinc steel plate P0.2 220 to 260MPa, tensile strength R m 340-420 MPa, elongation after break A 80mm 25-38%, and passing through a 180 DEG bending test with d being 0 a.
And (3) carrying out a hot-dip aluminum-zinc plated steel plate produced by the method according to part 1 of a GB/T228.1-2010 metal material tensile test: and (3) performing a tensile test according to a room temperature test method, testing the adhesive force of the coating according to a 180-degree bending test method specified in GB/T232-2010 metal material bending test method, wherein the bending core diameter d is 0a, and determining that the coating is qualified if no coating peeling occurs on the outer surface of the sample after the bending test, otherwise determining that the sample is unqualified, wherein the mechanical properties of the steel plate are shown in Table 4.
TABLE 4 mechanical properties of hot-dip aluminum-zinc plated steel sheets according to embodiments of the present invention
The hot-dip aluminum-zinc plated steel plate is used for a refrigerator bottom steel plate, the strength meets the requirement, the steel plate does not crack during stamping, and the use requirement is met.
In addition to the above embodiments, the present invention may have other embodiments. All technical solutions formed by adopting equivalent substitutions or equivalent transformations fall within the protection scope of the present invention.
Claims (6)
1. A hot-dip aluminum-zinc steel plate for a refrigerator bottom plate comprises the following chemical components in percentage by weight: c: 0.0010-0.0025%, Si is less than or equal to 0.03%, Mn: 0.35-0.45%, P: 0.050% -0.070%, S is less than or equal to 0.020%, Alt: 0.020-0.050%, Ti: 0.040% -0.060%, N is less than or equal to 0.0040%, and the balance is Fe and inevitable impurity elements; yield strength R of hot-dip aluminum-zinc steel plate with thickness of 0.20-0.28 mm P0.2 220 to 260MPa, tensile strength R m 340-420 MPa, elongation after break A 80mm 25-38%, and passing through a 180-degree bending test with d being 0 a; the thickness of the fingerprint-resistant film of the hot-dip aluminum-zinc plated steel plate is 0.8-1.4 g/m 2 The dynamic friction coefficient of the fingerprint-resistant film is 0.10-0.20.
2. The hot-dip aluminized and galvanized steel sheet for a refrigerator bottom plate according to claim 1, wherein the metallographic structure of the hot-dip aluminized and galvanized steel sheet is ferrite, and the grain size of the ferrite structure is I9-11 grade.
3. The hot-dip aluminized and galvanized steel sheet for a refrigerator bottom plate according to claim 1, wherein the hot-dip aluminized and galvanized steel sheet is press-formed into a refrigerator bottom plate, and when the maximum press height is 22mm, the hot-dip aluminized and galvanized steel sheet does not crack.
4. A method for manufacturing a hot-dip aluminum-zinc steel plate for a refrigerator bottom plate is characterized by comprising the following steps:
the method comprises the following steps of continuously casting molten steel to obtain a continuous casting slab, wherein the molten steel comprises the following chemical components in percentage by weight: c: 0.0010-0.0025%, Si is less than or equal to 0.03%, Mn: 0.35-0.45%, P: 0.050% -0.070%, S is less than or equal to 0.020%, Alt: 0.020-0.050%, Ti: 0.040% -0.060%, N is less than or equal to 0.0040%, and the balance is Fe and inevitable impurity elements;
heating the continuous casting plate blank to 1190-1230 ℃ by a heating furnace, and then carrying out hot rolling, wherein the hot rolling is a two-section rolling process, the rough rolling is 5-pass continuous rolling, and the finish temperature of the rough rolling is 1040-1100 ℃; the finish rolling is 7-pass continuous rolling, and the finish rolling finishing temperature is 900-940 ℃; after finish rolling, the thickness of the steel plate is 2.3-2.8 mm, laminar cooling adopts front-section cooling, and the coiling temperature is 660-700 ℃ to obtain a hot-rolled steel coil;
the hot rolled steel coil is uncoiled again, then is subjected to acid pickling, cold rolling, annealing in a horizontal continuous annealing furnace, hot-dip aluminum-zinc plating, flattening, fingerprint-resistant film coating and coiling to obtain a hot-dip aluminum-zinc plated steel plate with the thickness of 0.20-0.28 mm; the cold rolling reduction rate is 90-92%; annealing the cold-rolled strip steel in a hard rolling state in a horizontal continuous annealing furnace at the annealing speed of 121-140 m/min, wherein the temperature of the strip steel in a direct-fired section of the horizontal continuous annealing furnace is 630-670 ℃, the time of the strip steel in the direct-fired section is 9.5-11.0 s, the annealing temperature of the strip steel in a soaking section of the horizontal continuous annealing furnace is 760-800 ℃, and the annealing time of the strip steel in the soaking section is 25-30 s; the leveling elongation is 0.4% -0.8%; after roller coating, baking and curing, the fingerprint-resistant film thickness of the hot-dip aluminum-zinc steel plate is 0.8-1.4 g/m 2 The dynamic friction coefficient of the fingerprint-resistant film is 0.10-0.20.
5. As in claimThe method of manufacturing a hot-dip Al-Zn alloy steel sheet for a refrigerator base plate according to claim 4, wherein the metallographic structure of the hot-dip Al-Zn alloy steel sheet is ferrite, the grain size of the ferrite structure is I9 to 11 grades, and the yield strength R of the hot-dip Al-Zn alloy steel sheet is R P0.2 220 to 260MPa, tensile strength R m 340-420 MPa, elongation after break A 80mm 25-38%, and passing through a 180 DEG bending test with d being 0 a.
6. The method of manufacturing an Al-Zn-plated steel sheet for a refrigerator bottom plate according to claim 4, wherein the Al-Zn-plated steel sheet is press-formed into a refrigerator bottom plate without cracking when the maximum press height is 22 mm.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080083477A1 (en) * | 2004-10-20 | 2008-04-10 | Arcelor France | Hot-Dip Coating Method in a Zinc Bath for Strips of Iron/Carbon/Manganese Steel |
| CN103510002A (en) * | 2012-06-29 | 2014-01-15 | 上海梅山钢铁股份有限公司 | Gapless atom cold-rolled hot-galvanized steel plate and production method thereof |
| CN104593674A (en) * | 2015-01-21 | 2015-05-06 | 首钢总公司 | Hot-dip galvanized ultra-low carbon bake-hardening steel and production method thereof |
| CN106854729A (en) * | 2015-12-09 | 2017-06-16 | 上海梅山钢铁股份有限公司 | A kind of phosphorous gap-free atom cold-rolling galvanization steel plate and its manufacture method |
-
2021
- 2021-03-16 CN CN202110280721.2A patent/CN115074616A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080083477A1 (en) * | 2004-10-20 | 2008-04-10 | Arcelor France | Hot-Dip Coating Method in a Zinc Bath for Strips of Iron/Carbon/Manganese Steel |
| CN103510002A (en) * | 2012-06-29 | 2014-01-15 | 上海梅山钢铁股份有限公司 | Gapless atom cold-rolled hot-galvanized steel plate and production method thereof |
| CN104593674A (en) * | 2015-01-21 | 2015-05-06 | 首钢总公司 | Hot-dip galvanized ultra-low carbon bake-hardening steel and production method thereof |
| CN106854729A (en) * | 2015-12-09 | 2017-06-16 | 上海梅山钢铁股份有限公司 | A kind of phosphorous gap-free atom cold-rolling galvanization steel plate and its manufacture method |
Non-Patent Citations (1)
| Title |
|---|
| 马源 等: "固体润滑剂对镀铝锌耐指纹钢板表面摩擦特性的影响" * |
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