CN113005375A - Preparation method of Al-Mg-Zn-Cu alloy plate applied after paint baking and used for improving surface quality and strength - Google Patents
Preparation method of Al-Mg-Zn-Cu alloy plate applied after paint baking and used for improving surface quality and strength Download PDFInfo
- Publication number
- CN113005375A CN113005375A CN202110199354.3A CN202110199354A CN113005375A CN 113005375 A CN113005375 A CN 113005375A CN 202110199354 A CN202110199354 A CN 202110199354A CN 113005375 A CN113005375 A CN 113005375A
- Authority
- CN
- China
- Prior art keywords
- plate
- aging
- alloy
- temperature
- treatment
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/04—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon
- C22F1/047—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon of alloys with magnesium as the next major constituent
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D3/00—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
- B05D3/02—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by baking
- B05D3/0254—After-treatment
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C21/00—Alloys based on aluminium
- C22C21/06—Alloys based on aluminium with magnesium as the next major constituent
Abstract
The invention discloses a preparation method of an Al-Mg-Zn-Cu alloy plate which is applied after paint baking and is used for improving the surface quality and the strength, the yield strength of the plate prepared by the invention after paint baking can be improved by 44-77MPa compared with the yield strength of the plate prepared by the traditional treatment, the yield strength can reach 493MPa at most, and the paint baking increment can reach 180 MPa; compared with the traditional treatment, the tensile strength can be improved by 27-47MPa, and the maximum tensile strength can reach 561 MPa; the elongation is more than 8.0 percent; the traditional 5xxx series aluminum alloy has obvious sawtooth yield phenomenon, and the preparation method of the plate can reduce the sawtooth yield effect in the alloy, effectively improve the formability of the plate before baking finish and the surface quality and strength of the plate after baking finish, and ensure the service performance of the plate. Provides a new preparation method for the plate used after paint baking, and has wide industrial application prospect.
Description
Technical Field
The invention relates to the technical field of aluminum alloy plates, in particular to a preparation method of an Al-Mg-Zn-Cu alloy plate which is applied after paint baking and is used for improving the surface quality and the strength.
Background
With the rapid development of the automobile industry, the problems of ecological environment pollution, energy shortage, requirements of people on automobile safety performance and the like are increasingly highlighted, so that automobile manufacturers are forced to put the development core in the aspects of reducing the energy consumption of automobile products, reducing pollution, improving the automobile safety performance and the like, and the development and application of automobile lightweight technology and lightweight materials become hot problems of the current automobile industry.
The 5xxx series aluminum alloy has good formability, weldability, corrosion resistance and moderate strength, and is one of the best choices for lightweight automobile materials, but the surface of the punched 5xxx series aluminum alloy plate has surface defects such as Luders belt or orange peel, and is easy to soften in the paint baking process, so that the development of the 5xxx series aluminum alloy is greatly limited.
At present, in patent CN104862551, researchers have improved the strength of 5xxx series aluminum alloy after baking finish by adding a small amount of Cu and Zn elements, the increment of baking finish strength is about 50MPa, the baking finish hardening increment of the alloy sheet is improved by utilizing the aging precipitation strengthening capability of Cu and Zn atoms, and the adverse effect of natural aging caused by adding Cu and Zn at the same time on baking finish hardening is well avoided by pre-aging treatment, but the improvement degree of baking finish increment still cannot meet the requirements of the future automobile industry on the mechanical property and safety property of the alloy sheet. In order to better meet the requirements of practical application, the baking varnish hardening capacity and the surface quality of the alloy plate are urgently needed to be improved through component design and process regulation, and the method has important significance for rapidly promoting the lightweight process of an automobile and widely applying the high-strength 5xxx series aluminum alloy material to an automobile body outer plate.
Disclosure of Invention
The invention aims to provide a preparation method of an Al-Mg-Zn-Cu alloy plate which is applied after paint baking and improves the surface quality and the strength, so as to solve the problems in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme:
the preparation method of the Al-Mg-Zn-Cu alloy plate applied after paint baking and used for improving the surface quality and the strength comprises the following steps:
smelting → casting → homogenizing → milling face → hot rolling → cold rolling → improving the surface quality and strength, wherein the total rolling reduction rate is more than or equal to 90 percent, and the total cold rolling reduction rate is more than or equal to 80 percent.
Further, the improvement of the surface quality and the strength comprises the following steps:
the first step is as follows: directly carrying out solid solution on the cold-rolled aging-strengthened Al-Mg-Zn-Cu alloy plate (the temperature of the cold-rolled aging-strengthened Al-Mg-Zn-Cu alloy plate is kept for 10-30min in a salt bath furnace at 500-530 ℃ or kept for 15-120min in a medium temperature furnace at 460-490 ℃), wherein the quenching mode is direct water quenching;
the second step is that: performing pre-aging treatment immediately after quenching (keeping the temperature in an aging furnace at 60-100 ℃ for 8-50h), and standing the treated plate at room temperature (7-30 days);
the third step: pre-stretching the plate by 2 percent, and then simulating baking finish treatment (keeping the temperature at 180-185 ℃ for 20-30 min).
Further, the improvement of the surface quality and the strength comprises the following steps:
the first step is as follows: directly carrying out solid solution on the aging strengthening type Al-Mg-Zn-Cu alloy plate after cold rolling (keeping the temperature in a salt bath furnace at 530 ℃ for 10-30min or a medium temperature furnace at 490 ℃ for 15-120min), wherein the quenching mode is direct water quenching;
the second step is that: pre-aging treatment (keeping the temperature in an aging furnace at 60-100 ℃ for 8-50h) immediately after quenching;
the third step: 2% pre-stretching the plate, performing secondary aging treatment (keeping the temperature at 110-150 ℃ for 7-24h), and finally simulating paint baking treatment (keeping the temperature at 180-185 ℃ for 20-30 min);
further, the improvement of the surface quality and the strength comprises the following steps:
the first step is as follows: directly carrying out solid solution on the aging strengthening type Al-Mg-Zn-Cu alloy plate after cold rolling (keeping the temperature in a salt bath furnace at 530 ℃ for 10-30min or a medium temperature furnace at 490 ℃ for 15-120min), wherein the quenching mode is direct water quenching;
the second step is that: naturally aging (standing at-20-40 deg.C for 7-30 days) after quenching;
the third step: pre-stretching the plate by 2 percent, performing pre-aging treatment (keeping the temperature in an aging furnace at 60-100 ℃ for 8-50h), performing secondary aging treatment (keeping the temperature at 110-150 ℃ for 7-24h), and finally simulating paint baking treatment (keeping the temperature at 180-185 ℃ for 20-30 min);
further, the preparation method of the Al-Mg-Zn-Cu alloy plate which is applied after paint baking and used for improving the surface quality and the strength comprises the following chemical components in percentage by mass: 4.0 to 6.0 weight percent of Mg, 2.0 to 6.0 weight percent of Zn, 0 to 1.0 weight percent of Cu, less than or equal to 0.3 weight percent of Mn, less than or equal to 0.4 weight percent of Fe, less than or equal to 0.4 weight percent of Si, less than or equal to 0.1 weight percent of Cr, less than or equal to 0.3 weight percent of Zr, less than or equal to 0.1 weight percent of Ti, and the balance of Al and inevitable impurities, wherein the mass ratio of (Zn + Cu)/Mg is less than or equal to 1.5.
Compared with the prior art, the invention has the beneficial effects that:
1. the yield strength of the plate prepared by the invention after baking finish can be improved by 44-77MPa compared with the yield strength of the plate prepared by the traditional treatment, the yield strength can reach 493MPa at most, and the baking finish increment can reach 180 MPa; compared with the traditional treatment, the tensile strength can be improved by 27-47MPa, and the maximum tensile strength can reach 561 MPa; the elongation is more than 8.0 percent; the traditional 5xxx series aluminum alloy has obvious sawtooth yield phenomenon, and the preparation method of the plate can reduce the sawtooth yield effect in the alloy, effectively improve the formability of the plate before baking finish and the surface quality and strength of the plate after baking finish, and ensure the service performance of the plate. Provides a new preparation method for the plate used after paint baking, and has wide industrial application prospect.
2. The invention regulates and controls the strengthening phase T-Mg dispersed and distributed in the matrix by introducing the pre-aging and pre-stretching treatment method32(AlZnCu)49The size and number density of the phase enable the alloy treated by the new process to have higher baking finish performance, the addition of Cu element and the pre-aging treatment can improve the number density of GP zones in the alloy, and the GP zones are used as effective nucleation points of the T phase and can promote the dispersion and precipitation of the T phase.
3. The GP zone formed in the pre-aging process can consume a large amount of Mg solute atoms, so that the interaction between solid solution atoms and dislocation in the stamping process is reduced, the Luders effect and the sawtooth yield effect of the alloy are inhibited, the surface quality of the alloy is obviously improved, the deformation energy storage of the alloy can be improved by 2% pre-strain, the internal precipitated phase of the alloy is increased, and the aging precipitation effect of the alloy is improved.
Drawings
FIG. 1 is a schematic drawing of the tensile curve of an aluminum alloy plate prepared by the method for preparing an Al-Mg-Zn-Cu alloy plate for improving surface quality and strength, which is applied after paint baking;
FIG. 2 is a schematic view of the overall process of the method for preparing the Al-Mg-Zn-Cu alloy sheet with improved surface quality and strength after the baking finish of the invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1-2, the present invention provides a technical solution:
the preparation method of the Al-Mg-Zn-Cu alloy plate applied after paint baking and used for improving the surface quality and the strength comprises the following steps:
smelting → casting → homogenizing → milling → hot rolling → cold rolling → improving the surface quality and strength;
in the invention, the hot rolling total reduction rate is more than or equal to 90 percent, and the cold rolling total reduction rate is more than or equal to 80 percent.
In the invention, the improvement of the surface quality and the strength comprises the following steps:
the first step is as follows: directly carrying out solid solution on the cold-rolled aging-strengthened Al-Mg-Zn-Cu alloy plate (the temperature of the cold-rolled aging-strengthened Al-Mg-Zn-Cu alloy plate is kept for 10-30min in a salt bath furnace at 500-530 ℃ or kept for 15-120min in a medium temperature furnace at 460-490 ℃), wherein the quenching mode is direct water quenching;
the second step is that: performing pre-aging treatment immediately after quenching (keeping the temperature in an aging furnace at 60-100 ℃ for 8-50h), and standing the treated plate at room temperature (7-30 days);
the third step: 2% pre-stretching the plate, then simulating baking finish treatment (keeping the temperature at 180-185 ℃ for 20-30min)
In the invention, the improvement of the surface quality and the strength comprises the following steps:
the first step is as follows: directly carrying out solid solution on the aging strengthening type Al-Mg-Zn-Cu alloy plate after cold rolling (keeping the temperature in a salt bath furnace at 530 ℃ for 10-30min or a medium temperature furnace at 490 ℃ for 15-120min), wherein the quenching mode is direct water quenching;
the second step is that: pre-aging treatment (keeping the temperature in an aging furnace at 60-100 ℃ for 8-50h) immediately after quenching;
the third step: 2% pre-stretching the plate, performing secondary aging treatment (keeping the temperature at 110-150 ℃ for 7-24h), and finally simulating paint baking treatment (keeping the temperature at 180-185 ℃ for 20-30 min);
in the invention, the improvement of the surface quality and the strength comprises the following steps:
the first step is as follows: directly carrying out solid solution on the aging strengthening type Al-Mg-Zn-Cu alloy plate after cold rolling (keeping the temperature in a salt bath furnace at 530 ℃ for 10-30min or a medium temperature furnace at 490 ℃ for 15-120min), wherein the quenching mode is direct water quenching;
the second step is that: naturally aging (standing at-20-40 deg.C for 7-30 days) after quenching;
the third step: pre-stretching the plate by 2 percent, performing pre-aging treatment (keeping the temperature in an aging furnace at 60-100 ℃ for 8-50h), performing secondary aging treatment (keeping the temperature at 110-150 ℃ for 7-24h), and finally simulating paint baking treatment (keeping the temperature at 180-185 ℃ for 20-30 min);
in the invention, the preparation method of the Al-Mg-Zn-Cu alloy plate which is applied after paint baking and is used for improving the surface quality and the strength comprises the following chemical components in percentage by mass: 4.0 to 6.0 weight percent of Mg, 2.0 to 6.0 weight percent of Zn, 0 to 1.0 weight percent of Cu, less than or equal to 0.3 weight percent of Mn, less than or equal to 0.4 weight percent of Fe, less than or equal to 0.4 weight percent of Si, less than or equal to 0.1 weight percent of Cr, less than or equal to 0.3 weight percent of Zr, less than or equal to 0.1 weight percent of Ti, and the balance of Al and inevitable impurities, wherein the mass ratio of (Zn + Cu)/Mg is less than or equal to 1.5.
The ingot casting adopted by the invention is formed by casting industrial high-purity aluminum (Al: 99.90%, and others: 0.10%), industrial pure Mg, industrial pure Zn, Al-50 wt% Cu alloy, Al-10 wt% Mn alloy, Al-5 wt% Cr alloy, Al-10 wt% Zr, Al-10 wt% Ti and grain refiner Al-5 wt% Ti-1 wt% B;
the specific chemical components of the alloy of the embodiment are shown in the table 1;
TABLE 1 specific chemical composition of alloy (mass%; wt%)
The alloy ingot of the invention is homogenized in a medium temperature furnace, and then is milled, hot rolled, cold rolled and intermediate annealed, solution quenched and pre-aged, and the specific embodiment is as follows:
homogenizing 1#, 2#, 3# ingots, and the concrete process comprises the following steps: heating the fused and cast alloy from room temperature to 470 ℃ at the heating rate of 30 ℃/h, preserving the heat for 24h, and then cooling to room temperature at the cooling rate of 30 ℃/h; after milling the surface of the cast ingot after homogenization treatment, carrying out hot rolling at the temperature of 450 ℃ with the total rolling reduction rate of more than or equal to 90 percent to obtain a hot rolled plate with the thickness of 6 mm; then, carrying out first cold rolling with the total reduction rate of 50% to obtain a 3mm cold-rolled sheet, then carrying out intermediate annealing at 450 ℃ for 1h, and then carrying out second cold rolling with the total reduction rate of 67% to finally obtain a 1mm cold-rolled sheet of the alloy No. 1, 2 and 3;
comparative example 1
Carrying out solution treatment on a 1mm cold-rolled sheet of the 1# alloy obtained by the method in a salt bath furnace at 525 ℃ for 10min, and then directly carrying out water quenching; placing the quenched cold-rolled sheet into an aging furnace for pre-aging treatment at 80 ℃ for 12h, and then placing the cold-rolled sheet at room temperature for 7 days to obtain a T4P state; the other group of pre-aging is placed at room temperature for 7 days, and then is subjected to artificial aging treatment at 180 ℃ for 30min (simulating baking finish) to obtain a baking finish state; finally, tensile experiments are carried out on the T4P-state alloy and the baking varnish-state alloy, the strength increment before and after the alloy is baked with varnish is measured, and the specific results are shown in table 2; the baking finish process is also simulated in an aging furnace; the tensile curves before and after paint baking are shown in FIG. 1.
Comparative example 2
Carrying out solution treatment on a 1mm cold-rolled sheet of the 2# alloy obtained by the method in a salt bath furnace at 525 ℃ for 10min, and then directly carrying out water quenching; placing the quenched cold-rolled sheet into an aging furnace for pre-aging treatment at 80 ℃ for 12h, and then placing the cold-rolled sheet at room temperature for 7 days to obtain a T4P state; the other group of pre-aging is placed at room temperature for 7 days, and then is subjected to artificial aging treatment at 180 ℃ for 30min (simulating baking finish) to obtain a baking finish state; finally, tensile experiments are carried out on the T4P-state alloy and the baking varnish-state alloy, the strength increment before and after the alloy is baked with varnish is measured, and the specific results are shown in table 2; the tensile curves before and after paint baking are shown in FIG. 1.
Comparative example 3
Carrying out solution treatment on a 1mm cold-rolled sheet of the 3# alloy obtained by the method at 525 ℃ for 10min in a salt bath furnace, and then directly carrying out water quenching; placing the quenched cold-rolled sheet into an aging furnace for pre-aging treatment at 80 ℃ for 12h, and then placing the cold-rolled sheet at room temperature for 7 days to obtain a T4P state; the other group of pre-aging is placed at room temperature for 7 days, and then is subjected to artificial aging treatment at 180 ℃ for 30min (simulating baking finish) to obtain a baking finish state; finally, tensile experiments are carried out on the T4P-state alloy and the baking varnish-state alloy, the strength increment before and after the alloy is baked with varnish is measured, and the specific results are shown in the table; the tensile curves before and after paint baking are shown in FIG. 1.
Example 1
Carrying out solution treatment on a 1mm cold-rolled sheet of the 1# alloy obtained by the method at 480 ℃ for 30min in a medium temperature furnace, and then directly carrying out water quenching; placing the quenched cold-rolled sheet into an aging furnace for pre-aging treatment at 80 ℃ for 12h, and then placing for 7 days to obtain a T4P state; another group of pre-aging is placed at room temperature for 7 days, then 2% pre-stretching treatment is carried out, heat preservation is carried out at 180 ℃ for 30min (simulating baking finish), artificial aging treatment is carried out, strength increment before and after alloy baking finish is measured, and specific results are shown in table 2; the tensile curves before and after paint baking are shown in FIG. 1.
Example 2
Carrying out solution treatment on a 1mm cold-rolled sheet of the 1# alloy obtained by the method at 480 ℃ for 30min in a medium temperature furnace, and then directly carrying out water quenching; placing the quenched cold-rolled plate into an aging furnace for pre-aging treatment at 80 ℃ for 12h, and then placing the plate at room temperature; after the other group of pre-aging, 2% pre-stretching treatment is carried out, then the heat preservation is carried out for 13h secondary aging treatment at 140 ℃, the heat preservation is carried out for 30min (simulating baking finish) artificial aging treatment at 180 ℃, the strength increment before and after the alloy baking finish is measured, and the specific result is shown in table 2; the tensile curves before and after paint baking are shown in FIG. 1.
Example 3
Carrying out solution treatment on a 1mm cold-rolled sheet of the 1# alloy obtained by the method at 480 ℃ for 30min in a medium temperature furnace, and then directly carrying out water quenching; naturally aging and placing the quenched cold-rolled sheet at 20 ℃ for 14 days; after another group of natural aging, 2% pre-stretching treatment is carried out, then 90 ℃ heat preservation is carried out for 48h pre-aging treatment, then heat preservation is carried out at 140 ℃ for 13h secondary aging treatment, heat preservation is carried out at 180 ℃ for 30min (simulating baking finish) artificial aging treatment, the strength increment before and after alloy baking finish is measured, and the specific result is shown in table 2; the tensile curves before and after paint baking are shown in FIG. 1.
Example 4
Carrying out solution treatment on a 1mm cold-rolled sheet of the 2# alloy obtained by the method at 480 ℃ for 30min in a medium temperature furnace, and then directly carrying out water quenching; placing the quenched cold-rolled sheet into an aging furnace for pre-aging treatment at 80 ℃ for 12h, and then placing for 7 days to obtain a T4P state; another group of pre-aging is placed at room temperature for 7 days, then 2% pre-stretching treatment is carried out, heat preservation is carried out at 180 ℃ for 30min (simulating baking finish), artificial aging treatment is carried out, strength increment before and after alloy baking finish is measured, and specific results are shown in table 2; the tensile curves before and after paint baking are shown in FIG. 1.
Example 5
Carrying out solution treatment on a 1mm cold-rolled sheet of the 2# alloy obtained by the method at 480 ℃ for 30min in a medium temperature furnace, and then directly carrying out water quenching; placing the quenched cold-rolled plate into an aging furnace for pre-aging treatment at 80 ℃ for 12h, and then placing the plate at room temperature; after the other group of pre-aging, 2% pre-stretching treatment is carried out, then the heat preservation is carried out for 13h secondary aging treatment at 140 ℃, the heat preservation is carried out for 30min (simulating baking finish) artificial aging treatment at 180 ℃, the strength increment before and after the alloy baking finish is measured, and the specific result is shown in table 2; the tensile curves before and after paint baking are shown in FIG. 1.
Example 6
Carrying out solution treatment on a 1mm cold-rolled sheet of the 2# alloy obtained by the method at 480 ℃ for 30min in a medium temperature furnace, and then directly carrying out water quenching; naturally aging and placing the quenched cold-rolled sheet at 20 ℃ for 14 days; after another group of natural aging, 2% pre-stretching treatment is carried out, then 90 ℃ heat preservation is carried out for 48h pre-aging treatment, then heat preservation is carried out at 140 ℃ for 13h secondary aging treatment, heat preservation is carried out at 180 ℃ for 30min (simulating baking finish) artificial aging treatment, the strength increment before and after alloy baking finish is measured, and the specific result is shown in table 2; the tensile curves before and after paint baking are shown in FIG. 1.
Example 7
Carrying out solution treatment on a 1mm cold-rolled sheet of the 3# alloy obtained by the method at 480 ℃ for 30min in a medium temperature furnace, and then directly carrying out water quenching; placing the quenched cold-rolled sheet into an aging furnace for pre-aging treatment at 80 ℃ for 12h, and then placing for 7 days to obtain a T4P state; another group of pre-aging is placed at room temperature for 7 days, then 2% pre-stretching treatment is carried out, heat preservation is carried out at 180 ℃ for 30min (simulating baking finish), artificial aging treatment is carried out, strength increment before and after alloy baking finish is measured, and specific results are shown in table 2; the tensile curves before and after paint baking are shown in FIG. 1.
Example 8
Carrying out solution treatment on a 1mm cold-rolled sheet of the 3# alloy obtained by the method at 480 ℃ for 30min in a medium temperature furnace, and then directly carrying out water quenching; placing the quenched cold-rolled plate into an aging furnace for pre-aging treatment at 80 ℃ for 12h, and then placing the plate at room temperature; after the other group of pre-aging, 2% pre-stretching treatment is carried out, then the heat preservation is carried out for 13h secondary aging treatment at 140 ℃, the heat preservation is carried out for 30min (simulating baking finish) artificial aging treatment at 180 ℃, the strength increment before and after the alloy baking finish is measured, and the specific result is shown in table 2; the tensile curves before and after paint baking are shown in FIG. 1.
Example 9
Carrying out solution treatment on a 1mm cold-rolled sheet of the 3# alloy obtained by the method at 480 ℃ for 30min in a medium temperature furnace, and then directly carrying out water quenching; naturally aging and placing the quenched cold-rolled sheet at 20 ℃ for 14 days; after another group of natural aging, 2% pre-stretching treatment is carried out, then 90 ℃ heat preservation is carried out for 48h pre-aging treatment, then heat preservation is carried out at 140 ℃ for 13h secondary aging treatment, heat preservation is carried out at 180 ℃ for 30min (simulating baking finish) artificial aging treatment, the strength increment before and after alloy baking finish is measured, and the specific result is shown in table 2; the tensile curves before and after paint baking are shown in FIG. 1.
The mechanical properties of the 1#, 2#, and 3# alloys in different states are measured.
Table 2 mechanical properties of alloy sheets with different compositions after different heat treatments, examples 1, 4, and 7 are the first process, examples 2, 5, and 8 are the second process, and examples 3, 6, and 9 are the third process.
As can be seen from Table 2, the alloy plate material prepared by the invention has the advantages that the mass ratio of (Zn + Cu)/Mg of the 1#, 2#, 3# -Al-Mg-Zn-Cu alloys is less than 1.5, the yield strength and the tensile strength of the 1# alloy after the first process baking finish can reach 406MPa and 479MPa, the yield strength and the tensile strength of the 2# alloy after the first process baking finish can reach 457MPa and 522MPa, and the yield strength and the tensile strength of the 3# alloy after the first process baking finish can reach 493MPa and 545 MPa; the yield strength and tensile strength of the alloy 1 subjected to second-process paint baking can reach 431MPa and 494MPa, the yield strength and tensile strength of the alloy 2 subjected to second-process paint baking can reach 466MPa and 535MPa, and the yield strength and tensile strength of the alloy 3 subjected to second-process paint baking can reach 493MPa and 561 MPa; after the paint baking of the third process, the yield strength and the tensile strength of the alloy of the No. 1 alloy can reach 423MPa and 487MPa, after the paint baking of the third process, the yield strength and the tensile strength of the alloy of the No. 2 alloy can reach 466MPa and 540MPa, and after the paint baking of the third process, the yield strength and the tensile strength of the alloy of the No. 3 alloy can reach 488MPa and 555 MPa. The strength was significantly improved compared to comparative examples 1, 2 and 3, and the alloy saw teeth yield significantly less as seen from the shape of the teeth of the stretched wire saw in fig. 1.
As can be seen from Table 2 and FIG. 1, the yield strength of the panel of the invention can be improved by more than 150MPa after the panel is subjected to paint baking; in conclusion, the alloy components and the preparation process designed by the invention greatly improve the baking finish hardening capacity of the alloy, fully improve the baking finish softening problem of the traditional 5xxx series aluminum alloy, and improve the number density of GP zones in the alloy through the pre-aging and the addition of Cu elements, thereby promoting the precipitation of T-phase strengthening phases, improving the adverse effect of natural aging on the later baking finish treatment and improving the baking finish hardening capacity of the alloy; the pre-strain increases the deformation energy storage of the alloy, leads to increase of the internal precipitated phase of the alloy and improves the aging precipitation effect of the alloy.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (4)
1. The preparation method of the Al-Mg-Zn-Cu alloy plate applied after paint baking and used for improving the surface quality and the strength comprises the following processing steps:
smelting → casting → homogenizing → milling → hot rolling → cold rolling → improving the surface quality and strength. Wherein the hot rolling total reduction rate is more than or equal to 90 percent, and the cold rolling total reduction rate is more than or equal to 80 percent;
the method is characterized by comprising the following subsequent processing steps:
the first step is as follows: directly carrying out solid solution on the cold-rolled aging-strengthened Al-Mg-Zn-Cu alloy plate (the temperature of the cold-rolled aging-strengthened Al-Mg-Zn-Cu alloy plate is kept for 10-30min in a salt bath furnace at 500-530 ℃ or kept for 15-120min in a medium temperature furnace at 460-490 ℃), wherein the quenching mode is direct water quenching;
the second step is that: performing pre-aging treatment immediately after quenching (keeping the temperature in an aging furnace at 60-100 ℃ for 8-50h), and standing the treated plate at room temperature (7-30 days);
the third step: 2% pre-stretching is carried out on the plate, then baking finish treatment is simulated (heat preservation is carried out for 20-30min at 180-185 ℃), the baking finish increment can reach 170MPa after the plate is treated, and the plate has good surface quality.
2. The panel of claim 1, characterized by the subsequent processing steps of:
the first step is as follows: directly carrying out solid solution on the cold-rolled aging-strengthened Al-Mg-Zn-Cu alloy plate (the temperature of the cold-rolled aging-strengthened Al-Mg-Zn-Cu alloy plate is kept for 10-30min in a salt bath furnace at 500-530 ℃ or kept for 15-120min in a medium temperature furnace at 460-490 ℃), wherein the quenching mode is direct water quenching;
the second step is that: performing pre-aging treatment immediately after quenching (keeping the temperature in an aging furnace at 60-100 ℃ for 8-50 h);
the third step: the method comprises the steps of pre-stretching the plate by 2%, performing secondary aging treatment (keeping the temperature at 110-150 ℃ for 7-24 hours), and finally simulating baking finish treatment (keeping the temperature at 180-185 ℃ for 20-30 minutes), wherein the baking finish increment after the plate treatment can reach 170MPa, and the plate has good surface quality.
3. The panel of claim 1, wherein the subsequent processing steps are:
the first step is as follows: directly carrying out solid solution on the cold-rolled aging-strengthened Al-Mg-Zn-Cu alloy plate (the temperature of the cold-rolled aging-strengthened Al-Mg-Zn-Cu alloy plate is kept for 10-30min in a salt bath furnace at 500-530 ℃ or kept for 15-120min in a medium temperature furnace at 460-490 ℃), wherein the quenching mode is direct water quenching;
the second step is that: naturally aging (standing at-20-40 ℃ for 7-30 days) after quenching;
the third step: the method comprises the steps of pre-stretching 2% of a plate, pre-aging treatment (keeping the temperature in an aging furnace at 60-100 ℃ for 8-50 hours), secondary aging treatment (keeping the temperature at 110-150 ℃ for 7-24 hours), and finally simulating baking finish treatment (keeping the temperature at 180-185 ℃ for 20-30 minutes), wherein the baking finish increment after the plate treatment can reach 180MPa, and the plate has good surface quality.
4. An Al-Mg-Zn-Cu aluminum alloy sheet with good mechanical properties after paint baking as claimed in claims 1-3, wherein the alloy comprises the following chemical components by mass percent: 4.0 to 6.0 wt% of Mg, 2.0 to 6.0 wt% of Zn, 0 to 1.0 wt% of Cu, less than or equal to 0.3 wt% of Mn, less than or equal to 0.4 wt% of Fe, less than or equal to 0.4 wt% of Si, less than or equal to 0.1 wt% of Cr, less than or equal to 0.3 wt% of Zr, less than or equal to 0.1 wt% of Ti, and the balance of Al and inevitable impurities, wherein the mass ratio of (Zn + Cu)/Mg is less than or equal to 1.5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110199354.3A CN113005375A (en) | 2021-02-22 | 2021-02-22 | Preparation method of Al-Mg-Zn-Cu alloy plate applied after paint baking and used for improving surface quality and strength |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110199354.3A CN113005375A (en) | 2021-02-22 | 2021-02-22 | Preparation method of Al-Mg-Zn-Cu alloy plate applied after paint baking and used for improving surface quality and strength |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113005375A true CN113005375A (en) | 2021-06-22 |
Family
ID=76406784
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110199354.3A Pending CN113005375A (en) | 2021-02-22 | 2021-02-22 | Preparation method of Al-Mg-Zn-Cu alloy plate applied after paint baking and used for improving surface quality and strength |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113005375A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115110012A (en) * | 2022-06-20 | 2022-09-27 | 中国航发北京航空材料研究院 | Preparation method of 2024 aluminum alloy sheet for aircraft chemical milling part |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103255324A (en) * | 2013-04-19 | 2013-08-21 | 北京有色金属研究总院 | Aluminum alloy material suitable for manufacturing car body panel and preparation method |
| CN104018040A (en) * | 2014-06-23 | 2014-09-03 | 北京科技大学 | Automotive high-formability aluminum alloy material and preparation method thereof |
| CN104862551A (en) * | 2015-05-21 | 2015-08-26 | 北京科技大学 | Al-Mg-Cu-Zn series aluminum alloy and preparation method of aluminum alloy sheet |
| CN108359920A (en) * | 2018-01-25 | 2018-08-03 | 北京科技大学 | A kind of short route prepares the deformation heat treatment method of the anti-corrosion Al-Mg-Zn aluminium alloys of high-strength height |
| EP3305926B1 (en) * | 2016-10-05 | 2019-07-24 | Aleris Rolled Products Germany GmbH | Welded structural member and method of manufacturing and use thereof |
| CN110453121A (en) * | 2019-09-09 | 2019-11-15 | 广西南南铝加工有限公司 | A kind of 7xxx line aluminium alloy plate of high brightness and preparation method thereof |
| CN110541096A (en) * | 2019-09-11 | 2019-12-06 | 北京科技大学 | High-strength easy-to-weld Al-Mg-Zn-Cu alloy and preparation method thereof |
| WO2020185920A1 (en) * | 2019-03-13 | 2020-09-17 | Novelis Inc. | Age-hardenable and highly formable aluminum alloys, monolithic sheet made therof and clad aluminum alloy product comprising it |
| CN111705274A (en) * | 2020-06-15 | 2020-09-25 | 北京科技大学 | Processing method of Al-Zn-Mg- (Cu) alloy material |
-
2021
- 2021-02-22 CN CN202110199354.3A patent/CN113005375A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103255324A (en) * | 2013-04-19 | 2013-08-21 | 北京有色金属研究总院 | Aluminum alloy material suitable for manufacturing car body panel and preparation method |
| CN104018040A (en) * | 2014-06-23 | 2014-09-03 | 北京科技大学 | Automotive high-formability aluminum alloy material and preparation method thereof |
| CN104862551A (en) * | 2015-05-21 | 2015-08-26 | 北京科技大学 | Al-Mg-Cu-Zn series aluminum alloy and preparation method of aluminum alloy sheet |
| EP3305926B1 (en) * | 2016-10-05 | 2019-07-24 | Aleris Rolled Products Germany GmbH | Welded structural member and method of manufacturing and use thereof |
| CN108359920A (en) * | 2018-01-25 | 2018-08-03 | 北京科技大学 | A kind of short route prepares the deformation heat treatment method of the anti-corrosion Al-Mg-Zn aluminium alloys of high-strength height |
| WO2020185920A1 (en) * | 2019-03-13 | 2020-09-17 | Novelis Inc. | Age-hardenable and highly formable aluminum alloys, monolithic sheet made therof and clad aluminum alloy product comprising it |
| CN110453121A (en) * | 2019-09-09 | 2019-11-15 | 广西南南铝加工有限公司 | A kind of 7xxx line aluminium alloy plate of high brightness and preparation method thereof |
| CN110541096A (en) * | 2019-09-11 | 2019-12-06 | 北京科技大学 | High-strength easy-to-weld Al-Mg-Zn-Cu alloy and preparation method thereof |
| CN111705274A (en) * | 2020-06-15 | 2020-09-25 | 北京科技大学 | Processing method of Al-Zn-Mg- (Cu) alloy material |
Non-Patent Citations (1)
| Title |
|---|
| 黄元春等: "预处理对Al-Mg-Si合金成形性能和烘烤硬化性能的影响", 《热加工工艺》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115110012A (en) * | 2022-06-20 | 2022-09-27 | 中国航发北京航空材料研究院 | Preparation method of 2024 aluminum alloy sheet for aircraft chemical milling part |
| CN115110012B (en) * | 2022-06-20 | 2023-10-20 | 中国航发北京航空材料研究院 | Preparation method of 2024 aluminum alloy sheet for chemically-milled parts of aircraft |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2015127805A1 (en) | High temperature baking hardened aluminum alloy material used for automobile body and preparation method thereof | |
| CN105441837B (en) | Treatment method for improving forming properties and strengths of 7xxx-series aluminium alloy thin plates | |
| WO2015109893A1 (en) | Al-mg-si-cu-zn series alloy of fast ageing response type and preparation method therefor | |
| CN106521253A (en) | High-formability Al-Mg-Si alloy and manufacturing method thereof | |
| CN104313413B (en) | A kind of Al-Mg-Zn system alloy and the preparation method of sheet alloy thereof | |
| CN111424197A (en) | Corrosion-resistant aluminum alloy for aviation and preparation method thereof | |
| CN112458344B (en) | High-strength corrosion-resistant aluminum alloy and preparation method and application thereof | |
| CN110629083B (en) | Marine 5083 aluminum alloy plate and preparation process thereof | |
| CN114058885B (en) | 6XXX series aluminum alloy plate and preparation method and welding method thereof | |
| CN107723634A (en) | Realize the heat treatment method and aviation alloyed aluminium sheet material of T77 three-step agings | |
| CN107354351A (en) | A kind of appearance member aluminium alloy and its processing method | |
| CN110453121A (en) | A kind of 7xxx line aluminium alloy plate of high brightness and preparation method thereof | |
| CN112195376A (en) | 6xxx series aluminum alloy plate for high-strength automobile body and preparation method thereof | |
| CN113913654A (en) | Preparation method of 6-series aluminum plate for battery pack lower shell of electric automobile | |
| CN113278825B (en) | Preparation method of single-side high-glossiness 6061-H22 state aluminum alloy mirror panel | |
| CN113005375A (en) | Preparation method of Al-Mg-Zn-Cu alloy plate applied after paint baking and used for improving surface quality and strength | |
| CN110396628B (en) | Aluminum alloy and preparation method thereof | |
| CN112522550B (en) | Aluminum alloy with rapid aging response and preparation method and application thereof | |
| WO2024051856A1 (en) | Manufacturing method for improving edge fitting properties of 6016 automobile stamped sheets | |
| CN108913925B (en) | 6-series alloy anodized aluminum plate strip for mobile phone frame and preparation method thereof | |
| CN108193101B (en) | Er, Zr and Si microalloyed Al-Mg-Cu alloy and thermomechanical treatment process thereof | |
| CN112095039B (en) | Aluminum alloy plate for automobile body and preparation method thereof | |
| CN110656268B (en) | High-strength anti-fatigue aluminum alloy and preparation method thereof | |
| JPS6389649A (en) | Manufacture of al-mg-zn alloy material having superior formability | |
| JPH0547615B2 (en) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210622 |