Al-mg-si alloy sheet, and preparation method therefor and use thereof

Abstract

The present invention provides an Al-Mg-Si alloy sheet, and a preparation method therefor and a use thereof. The Al-Mg-Si alloy sheet comprises, in percentage by mass, 0.50%-1.5% of Mg, 0.49%-0.53% of Si, 0.11%-0.18% of Fe, 0.03%-0.05% of La, 0.005%-0.02% of B, less than or equal to 0.02% of impurities, and the balance being Al, wherein the mass ratio of Mg to Si is greater than 1.0. In the present invention, the Al-Mg-Si alloy sheet has relatively high strength, electrical conductivity and fatigue resistance.

Description

Al-Mg-Si alloy plate and preparation method and application thereof TECHNICAL FIELD

[0001] The application relates to an Al-Mg-Si alloy plate, in particular to an Al-Mg-Si alloy plate and a preparation method and application thereof, and belongs to the technical field of aluminum alloy profile manufacturing. BACKGROUND

[0002] In the fields of electric / electronic industry or automobile industry, most of conductive materials select copper and its alloy as main materials, but the copper has large density and high specific gravity, which increases the weight of the conductive material, especially in the field of automobile industry, the automobile energy consumption is significantly increased, which is not conducive to realizing the green and low-carbon requirement; due to the advantages of rich aluminum resources, light specific gravity and low price, the aluminum alloy is widely concerned, and the Al-Mg-Si series aluminum alloy becomes the first choice material due to the excellent easy processability.

[0003] The strength and the electrical conductivity of the Al-Mg-Si alloy plate and the fatigue resistance and the electrical conductivity are inversely proportional, so that the Al-Mg-Si alloy plate is difficult to have good electrical conductivity, strength and fatigue resistance.

[0004] An Al-Mg-Si alloy plate with good electrical conductivity, strength and fatigue resistance has good application prospect. SUMMARY

[0005] The application provides an Al-Mg-Si alloy plate and a preparation method and application thereof, which have good electrical conductivity, strength and fatigue resistance and have good application prospect.

[0006] The application provides an Al-Mg-Si alloy plate, which comprises the following components in percentage by mass: 0.50-1.5% of Mg, 0.49-0.53% of Si, 0.11-0.18% of Fe, 0.03-0.05% of La, 0.005-0.02% of B, not more than 0.02% of impurities and the balance of Al; wherein the mass ratio of the Mg to the Si is greater than 1.0.

[0007] Optionally, the mass ratio of the Mg to the Si is (1.0-3.0):1, and the mass ratio of the Mg to the Si is not equal to 1.

[0008] Optionally, the microstructure of the Al-Mg-Si alloy plate comprises Mg2Si phase and Mg5Si6 phase; the proportion of the Mg2Si phase in the microstructure of the Al-Mg-Si alloy plate is 0.5% to 1%, and the proportion of the Mg5Si6 phase in the microstructure of the Al-Mg-Si alloy plate is 10% to 15%.

[0009] Optionally, the Al-Mg-Si alloy plate has a strength of ≥400 MPa, an electrical conductivity of ≥58% IACS, and a crack propagation rate curve slope of ≤3.0.

[0010] Optionally, the Al-Mg-Si alloy plate is prepared by at least a method comprising the following processes: sequentially performing homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling processing on an ingot to obtain the Al-Mg-Si alloy plate, wherein the temperature of the aging heat treatment is 155-165℃, the time is 5-10h, and the deformation amount of the cold rolling processing is 40%-55%.

[0011] The application further provides a preparation method of the Al-Mg-Si alloy plate as described above, comprising the following steps: sequentially performing homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling processing on an ingot to obtain the Al-Mg-Si alloy plate; wherein the chemical composition of the ingot is Mg 0.50%-1.5%, Si 0.49%-0.53%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, and the balance being Al, and the mass ratio of Mg and Si is greater than 1.0.

[0012] Optionally, the temperature of the aging heat treatment is 155-165℃, the time is 5-7h, and the deformation amount of the cold rolling processing is 40%-55%.

[0013] Optionally, the temperature of the homogenization treatment is 530-550℃, the time is 12-24h, and / or the temperature of the solid solution heat treatment is 510-530℃, the time is 2-7h.

[0014] Optionally, the mass ratio of Mg and Si is (1.0-3.0):1, and the mass ratio of Mg and Si is not equal to 1.

[0015] The application further provides an apparatus comprising the Al-Mg-Si alloy plate as described above or obtained by the preparation method as described above.

[0016] The application provides an Al-Mg-Si alloy plate and a preparation method and application thereof. BRIEF DESCRIPTION OF DRAWINGS

[0017] Fig. 1 is an electron microscope image of Mg2Si phase and Mg5Si6 phase in the Al-Mg-Si alloy plate of Example 1. DETAILED DESCRIPTION

[0018] In order to make the objects, technical solutions and advantages of the present application clearer, the following will combine the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0019] The embodiment of the present application provides an Al-Mg-Si alloy plate, and the Al-Mg-Si alloy plate comprises the following components in percentage by mass: Mg 0.50%-1.5%, Si 0.49%-0.53%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, and the balance is Al; wherein the mass ratio of Mg and Si is greater than 1.0.

[0020] According to the research and analysis of the inventor: the mass ratio of Mg / Si greater than 1.0 is beneficial to the precipitation of fine dispersed phases in the matrix of the Al-Mg-Si alloy plate, including Mg2Si phase and Mg5Si6 phase, so that the Al-Mg-Si alloy plate has higher strength and fatigue resistance, and is especially beneficial to obtaining fine Mg5Si6 phase, more significantly improving the fatigue crack propagation resistance of the Al-Mg-Si alloy plate, and reducing the fatigue crack propagation rate of the Al-Mg-Si alloy plate, which is specifically manifested as that the crack propagation rate curve slope of the Al-Mg-Si alloy plate is less than or equal to 3.0. The above-mentioned Mg and Si cooperate to improve the content of the above-mentioned dispersed phase, and at the same time, effectively refine and round the harmful coarse precipitated phases such as Al / Fe, further improving the workability and fatigue resistance of the Al-Mg-Si alloy plate; meanwhile, the addition of Fe is beneficial to improving the electrical conductivity of the Al-Mg-Si alloy plate; the addition of appropriate amount of La in the above-mentioned Al-Mg-Si alloy plate is beneficial to purifying the melt of the Al-Mg-Si alloy plate, reducing the grain size of the Al-Mg-Si alloy plate, and thus improving the electrical conductivity of the Al-Mg-Si alloy plate; the addition of B element helps to refine the grain of the Al-Mg-Si alloy plate, purify the grain boundary, and is beneficial to improving the strength and electrical conductivity of the Al-Mg-Si alloy plate; the embodiment of the present application limits Mg 0.50-1.5%, Si 0.49-0.53%, Fe 0.11-0.18%, La 0.03-0.05%, and B 0.005-0.02%, wherein the mass ratio of Mg and Si is greater than 1.0, so that the various elements cooperate more optimally, and thus the Al-Mg-Si alloy plate has better electrical conductivity, strength and fatigue resistance.

[0021] Exemplarily, in the Al-Mg-Si alloy plate, the mass percentage content of Mg can be 0.50%, 0.60%, 0.70%, 0.80%, 0.90%, 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, or a range consisting of any two of them, the mass percentage content of Si can be 0.49%, 0.50%, 0.51%, 0.52%, 0.53%, or a range consisting of any two of them, the mass percentage content of Fe can be 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, or a range consisting of any two of them, the mass percentage content of La can be 0.03%, 0.04%, 0.05%, or a range consisting of any two of them, and the mass percentage content of B can be 0.005%, 0.01%, 0.02%, or a range consisting of any two of them.

[0022] Further, the impurities include at least one of Ti, Mn, Cr, and V, and the mass percentage of Ti is ≤0.005%, the mass percentage of Mn is ≤0.005%, the mass percentage of Cr is ≤0.005%, and the mass percentage of V is ≤0.005% in the Al-Mg-Si alloy sheet, which helps to improve the electrical conductivity, strength, and fatigue resistance of the Al-Mg-Si alloy sheet.

[0023] In some embodiments, the mass ratio of Mg to Si is (1.0-3.0):1, for example, 1.1:1, 1.5:1, 2.0:1, 2.5:1, 3.0:1, or a range consisting of any two of them, and the mass ratio of Mg to Si is not equal to 1, and the electrical conductivity, strength, and fatigue resistance of the Al-Mg-Si alloy sheet are better.

[0024] The microstructure of the Al-Mg-Si alloy sheet has a key impact on its performance.

[0025] The microstructure of the Al-Mg-Si alloy sheet includes Mg2Si phase and Mg5Si6 phase.

[0026] In some embodiments, the proportion of the Mg2Si phase in the microstructure of the Al-Mg-Si alloy sheet is 0.5%-1%, for example, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, or a range consisting of any two of them, and the proportion of the Mg5Si6 phase in the microstructure of the Al-Mg-Si alloy sheet is 10%-15%, for example, 10%, 11%, 12%, 13%, 14%, 15%, or a range consisting of any two of them, so that the Al-Mg-Si alloy sheet not only has good electrical conductivity but also has high strength and fatigue resistance.

[0027] The size range of the Mg2Si phase and the Mg5Si6 phase is 10-50 nm in diameter, 40-100 nm in length, and 0.5-3 nm in width, respectively. These fine dispersed phases help to improve the strength of the Al-Mg-Si alloy sheet. As can be seen from the proportion of the Mg2Si phase and the Mg5Si6 phase in the microstructure of the Al-Mg-Si alloy sheet, a fine dispersed phase with a high number density is formed in the crystal of the Al-Mg-Si alloy sheet, which reduces the propagation rate of the fatigue crack of the Al-Mg-Si alloy sheet, and the slope of the crack propagation rate curve of the Al-Mg-Si alloy sheet is ≤3.0, so that the Al-Mg-Si alloy sheet not only has good electrical conductivity but also has high strength and fatigue resistance.

[0028] The above proportions are volume fraction proportions, i.e. the volume percentage of Mg2Si phase to the volume of the microstructure of the Al-Mg-Si alloy sheet is 0.5% to 1%, and the volume percentage of Mg5Si6 phase to the volume of the microstructure of the Al-Mg-Si alloy sheet is 10% to 15%.

[0029] In some embodiments, the Al-Mg-Si alloy sheet has a strength ≥ 400 MPa, an electrical conductivity ≥ 58% IACS, and a crack propagation rate curve slope ≤ 3.0.

[0030] The crack propagation rate curve slope refers to the slope of the linear fitting line of the crack propagation rate da / dN and the stress field intensity factor ΔK, and the smaller the value, the better the fatigue resistance of the material. The crack propagation rate curve slope of the Al-Mg-Si alloy sheet of the present application is ≤ 3.0, indicating that the Al-Mg-Si alloy sheet has good fatigue resistance and thus has a longer service life.

[0031] The Al-Mg-Si alloy sheet has not only the advantages of light weight and good processing performance, but also good electrical conductivity, strength and fatigue resistance, and can be processed into an electrically conductive sheet and the like, and has good application prospects.

[0032] The Al-Mg-Si alloy sheet is prepared by a method comprising at least the following processes:

[0033] The ingot is subjected to homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling in sequence to obtain the Al-Mg-Si alloy sheet, wherein the aging heat treatment temperature is 155-165°C, such as 155°C, 156°C, 157°C, 158°C, 159°C, 160°C, 161°C, 162°C, 163°C, 164°C, 165°C or a range formed by any two of them, the aging heat treatment time is 5-10h, such as 5h, 6h, 7h, 8h, 9h, 10h or a range formed by any two of them, and the deformation amount of cold rolling is 40%-55%, such as 40%, 45%, 50%, 55% or a range formed by any two of them.

[0034] It can be understood that the chemical composition of the ingot satisfies Mg 0.50-1.5%, Si 0.49-0.53%, Fe 0.11-0.18%, La 0.03-0.05%, B 0.005-0.02%, impurities ≤ 0.02%, the balance being Al, and the mass ratio of Mg and Si is greater than 1.0.

[0035] The casting ingot is treated by homogenization, solid solution heat treatment, aging heat treatment and cold rolling, so that the treated casting ingot forms fine and dispersed phases such as Mg2Si phase and Mg5Si6 phase, and the electrical conductivity, strength and fatigue resistance of the Al-Mg-Si alloy plate are improved.

[0036] The embodiment of the present application also provides a preparation method of the Al-Mg-Si alloy plate, which comprises the following steps: sequentially performing homogenization, solid solution heat treatment, aging heat treatment and cold rolling on a casting ingot to obtain the Al-Mg-Si alloy plate; wherein the chemical composition of the casting ingot is Mg 0.50-1.5%, Si 0.49-0.53%, Fe 0.11-0.18%, La 0.03-0.05%, B 0.005-0.02%, impurities ≤0.02%, and the balance is Al, and the mass ratio of Mg to Si is greater than 1.0.

[0037] The homogenization, solid solution heat treatment, aging heat treatment and cold rolling are combined to achieve better synergistic effect, so that the Al-Mg-Si alloy plate has good electrical conductivity, strength and fatigue resistance. The preparation method of the Al-Mg-Si alloy plate is simple, low in cost and easy to popularize, and an Al-Mg-Si alloy plate with good electrical conductivity, strength and fatigue resistance can be obtained by the preparation method.

[0038] The embodiment of the present application does not limit the preparation process of the casting ingot, and the commonly used methods in the art can be used.

[0039] In some embodiments, the temperature of the aging heat treatment is 155-165℃, and the time is 5-7h; and the deformation amount of the cold rolling is 40%-55%. The aging heat treatment process causes alloy elements to further precipitate to form fine and dispersed phases such as Mg2Si phase and Mg5Si6 phase, which is beneficial to improving the strength of the Al-Mg-Si alloy plate and significantly reducing the fatigue crack propagation rate of the Al-Mg-Si alloy plate. By further limiting the temperature of the aging heat treatment to 155-165℃ and the time to 5-7h, the number density and uniformity of the fine and dispersed phases such as Mg2Si phase and Mg5Si6 phase are improved, and the strength and fatigue resistance of the Al-Mg-Si alloy plate are significantly improved. The cold rolling can improve the deformation energy storage of the Al-Mg-Si alloy plate and increase the dislocation number, thereby greatly improving the strength of the Al-Mg-Si alloy plate. By further limiting the deformation amount of the cold rolling to 40%-55%, the electrical conductivity, strength and fatigue resistance of the Al-Mg-Si alloy plate are improved.

[0040] Exemplarily, the temperature of the above-mentioned aging heat treatment can be 155℃, 158℃, 160℃, 162℃, 165℃, or a range formed by any two of them, and the time of the aging heat treatment can be 5h, 5.5h, 6h, 6.5h, 7h, or a range formed by any two of them, preferably 160℃, 7h, the fine and dispersed phase Mg2Si phase and Mg5Si6 phase are precipitated better, especially the Mg5Si6 phase is precipitated better, so that the electrical conductivity, strength and fatigue resistance of the Al-Mg-Si alloy plate are better improved.

[0041] The homogenization treatment can improve the uneven state of the above-mentioned ingot crystal structure, reduce or eliminate the intracrystalline segregation, and help the fine and dispersed phase Mg2Si phase and Mg5Si6 phase to be precipitated more uniformly.

[0042] In some embodiments, the temperature of the above-mentioned homogenization treatment is 530-550℃, and the time is 12-24h, which is more conducive to improving the uneven state of the above-mentioned ingot crystal structure, reducing or eliminating the intracrystalline segregation, and further helping the fine and dispersed phase Mg2Si phase and Mg5Si6 phase to be precipitated more uniformly.

[0043] Since the heating speed and cooling speed of the homogenization treatment also affect the effect of the homogenization treatment and further affect the performance of the product, when the heating speed of the above-mentioned homogenization treatment is 100-300℃ / h, such as 100℃ / h, 150℃ / h, 200℃ / h, 250℃ / h, 300℃ / h, or a range formed by any two of them, and the cooling speed is 50-70℃ / s, such as 50℃ / s, 55℃ / s, 60℃ / s, 65℃ / s, 70℃ / s, or a range formed by any two of them, the effect of the homogenization treatment is better, and further the performance of the product is improved.

[0044] The solid solution heat treatment is to obtain the maximum supersaturation so as to facilitate the effect of the subsequent aging heat treatment, and the excess phase in the Al-Mg-Si alloy plate is fully dissolved into the matrix through the solid solution heat treatment, and the eutectic silicon phase is spheroidized, so that the Al-Mg-Si alloy plate has better strength and fatigue resistance. Selecting appropriate solid solution temperature and holding time can ensure that the Al-Mg-Si alloy plate matrix is strengthened to a greater extent. When the temperature of the above-mentioned solid solution heat treatment is 510-530℃, such as 510℃, 515℃, 520℃, 525℃, 530℃, or a range formed by any two of them, and the time of the solid solution heat treatment is 2-7h, such as 2h, 3h, 4h, 5h, 6h, 7h, or a range formed by any two of them, the effect of the solid solution heat treatment is better.

[0045] The third aspect of the present application provides a device comprising the above-mentioned Al-Mg-Si alloy plate or the Al-Mg-Si alloy plate obtained by the above-mentioned preparation method.

[0046] The application will be described in more detail below with reference to specific examples and comparative examples.

[0047] Example 1

[0048] The embodiment provides a preparation method of an Al-Mg-Si alloy plate, comprising the following steps:

[0049] The cast ingot is sequentially subjected to homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling processing to obtain the Al-Mg-Si alloy plate; wherein the chemical composition of the cast ingot is Mg 0.8%, Si 0.53%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, the balance being Al, and the mass ratio of Mg and Si is 1.5; the temperature of the aging heat treatment is 155°C, and the time is 7h; the deformation amount of the cold rolling processing is 55%; the temperature of the homogenization treatment is 530°C, and the time is 24h; the temperature of the solid solution heat treatment is 510°C, and the time is 7h.

[0050] Example 2

[0051] The embodiment provides a preparation method of an Al-Mg-Si alloy plate, comprising the following steps:

[0052] The cast ingot is sequentially subjected to homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling processing to obtain the Al-Mg-Si alloy plate; wherein the chemical composition of the cast ingot is Mg 0.8%, Si 0.53%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, the balance being Al, and the mass ratio of Mg and Si is 1.5; the temperature of the aging heat treatment is 155°C, and the time is 7h; the deformation amount of the cold rolling processing is 55%; the temperature of the homogenization treatment is 530°C, and the time is 24h; the temperature of the solid solution heat treatment is 510°C, and the time is 7h.

[0053] Example 3

[0054] The embodiment provides a preparation method of an Al-Mg-Si alloy plate, comprising the following steps:

[0055] The cast ingot is sequentially subjected to homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling to obtain an Al-Mg-Si alloy plate; wherein the chemical composition of the cast ingot is Mg 1.5%, Si 0.49%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, the balance being Al, and the mass ratio of Mg and Si is 3.06; the aging heat treatment temperature is 155℃, and the time is 7h; the deformation amount of the cold rolling is 55%; the homogenization treatment temperature is 530℃, and the time is 24h; and the solid solution heat treatment temperature is 510℃, and the time is 7h.

[0056] Example 4

[0057] The present embodiment provides a preparation method of an Al-Mg-Si alloy plate, comprising the following steps:

[0058] The cast ingot is sequentially subjected to homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling to obtain an Al-Mg-Si alloy plate; wherein the chemical composition of the cast ingot is Mg 1.5%, Si 0.49%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, the balance being Al, and the mass ratio of Mg and Si is 3.06; the aging heat treatment temperature is 155℃, and the time is 7h; the deformation amount of the cold rolling is 55%; the homogenization treatment temperature is 530℃, and the time is 24h; and the solid solution heat treatment temperature is 510℃, and the time is 7h.

[0059] Example 5

[0060] The present embodiment provides a preparation method of an Al-Mg-Si alloy plate, comprising the following steps:

[0061] The cast ingot is sequentially subjected to homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling to obtain an Al-Mg-Si alloy plate; wherein the chemical composition of the cast ingot is Mg 1.5%, Si 0.49%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, the balance being Al, and the mass ratio of Mg and Si is 3.06; the aging heat treatment temperature is 155℃, and the time is 7h; the deformation amount of the cold rolling is 55%; the homogenization treatment temperature is 530℃, and the time is 24h; and the solid solution heat treatment temperature is 510℃, and the time is 7h.

[0062] Example 6

[0063] The present embodiment provides a preparation method of an Al-Mg-Si alloy plate, comprising the following steps:

[0064] The cast ingot is sequentially subjected to homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling to obtain an Al-Mg-Si alloy plate; wherein the chemical composition of the cast ingot is Mg 1.0%, Si 0.5%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, the balance being Al and the mass ratio of Mg and Si being 2; the temperature of the aging heat treatment is 155℃, and the time is 7h; the deformation of the cold rolling is 55%; the temperature of the homogenization treatment is 550℃, and the time is 12h; the temperature of the solid solution heat treatment is 510℃, and the time is 7h.

[0065] Example 7

[0066] The present embodiment provides a preparation method of an Al-Mg-Si alloy plate, comprising the following steps:

[0067] The cast ingot is sequentially subjected to homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling to obtain an Al-Mg-Si alloy plate; wherein the chemical composition of the cast ingot is Mg 1.0%, Si 0.5%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, the balance being Al and the mass ratio of Mg and Si being 2; the temperature of the aging heat treatment is 155℃, and the time is 7h; the deformation of the cold rolling is 55%; the temperature of the homogenization treatment is 530℃, and the time is 24h; the temperature of the solid solution heat treatment is 530℃, and the time is 2h.

[0068] Example 8

[0069] The present embodiment provides a preparation method of an Al-Mg-Si alloy plate, comprising the following steps:

[0070] The cast ingot is sequentially subjected to homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling to obtain an Al-Mg-Si alloy plate; wherein the chemical composition of the cast ingot is Mg 1.0%, Si 0.5%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, the balance being Al and the mass ratio of Mg and Si being 2; the temperature of the aging heat treatment is 155℃, and the time is 7h; the deformation of the cold rolling is 55%; the temperature of the homogenization treatment is 560℃, and the time is 24h; the temperature of the solid solution heat treatment is 510℃, and the time is 7h.

[0071] Example 9

[0072] The present embodiment provides a preparation method of an Al-Mg-Si alloy plate, comprising the following steps:

[0073] The Al-Mg-Si alloy plate is obtained by sequentially performing homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling on the ingot; wherein the chemical composition of the ingot is Mg 1.0%, Si 0.5%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, and the balance of Al, and the mass ratio of Mg and Si is 2; the temperature of the aging heat treatment is 155℃, and the time is 7h; the deformation of the cold rolling is 55%; the temperature of the homogenization treatment is 530℃, and the time is 24h; the temperature of the solid solution heat treatment is 550℃, and the time is 7h.

[0074] Example 10

[0075] The embodiment provides a preparation method of an Al-Mg-Si alloy plate, which comprises the following steps:

[0076] The Al-Mg-Si alloy plate is obtained by sequentially performing homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling on the ingot; wherein the chemical composition of the ingot is Mg 0.8%, Si 0.53%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, and the balance of Al, and the mass ratio of Mg and Si is 1.5; the temperature of the aging heat treatment is 180℃, and the time is 3h; the deformation of the cold rolling is 55%; the temperature of the homogenization treatment is 530℃, and the time is 24h; the temperature of the solid solution heat treatment is 510℃, and the time is 7h.

[0077] Example 11

[0078] The embodiment provides a preparation method of an Al-Mg-Si alloy plate, which comprises the following steps:

[0079] The Al-Mg-Si alloy plate is obtained by sequentially performing homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling on the ingot; wherein the chemical composition of the ingot is Mg 0.8%, Si 0.53%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, and the balance of Al, and the mass ratio of Mg and Si is 1.5; the temperature of the aging heat treatment is 155℃, and the time is 7h; the deformation of the cold rolling is 35%; the temperature of the homogenization treatment is 530℃, and the time is 24h; the temperature of the solid solution heat treatment is 510℃, and the time is 7h.

[0080] Example 12

[0081] The embodiment is basically the same as the embodiment 10, and the difference lies in that:

[0082] The temperature of the aging heat treatment is 145℃.

[0083] The present embodiment provides a preparation method of an Al-Mg-Si alloy plate, comprising the following steps:

[0084] The cast ingot is sequentially subjected to homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling to obtain an Al-Mg-Si alloy plate; wherein the chemical composition of the cast ingot is Mg 0.8%, Si 0.53%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, the balance being Al and the mass ratio of Mg and Si being 1.5; the temperature of the aging heat treatment is 145℃ and the time is 3h; the deformation amount of the cold rolling is 55%; the temperature of the homogenization treatment is 530℃ and the time is 24h; the temperature of the solid solution heat treatment is 510℃ and the time is 7h.

[0085] Example 13

[0086] The present embodiment is basically the same as Example 10, except that:

[0087] The deformation amount of the cold rolling is 65%.

[0088] The present embodiment provides a preparation method of an Al-Mg-Si alloy plate, comprising the following steps:

[0089] The cast ingot is sequentially subjected to homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling to obtain an Al-Mg-Si alloy plate; wherein the chemical composition of the cast ingot is Mg 0.8%, Si 0.53%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, the balance being Al and the mass ratio of Mg and Si being 1.5; the temperature of the aging heat treatment is 145℃ and the time is 3h; the deformation amount of the cold rolling is 55%; the temperature of the homogenization treatment is 530℃ and the time is 24h; the temperature of the solid solution heat treatment is 510℃ and the time is 7h.

[0090] Comparative Example 1

[0091] The present embodiment provides a preparation method of an Al-Mg-Si alloy plate, comprising the following steps:

[0092] The cast ingot is sequentially subjected to homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling to obtain an Al-Mg-Si alloy plate; wherein the chemical composition of the cast ingot is Mg 0.8%, Si 0.8%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, the balance being Al and the mass ratio of Mg and Si being 1; the temperature of the aging heat treatment is 155°C and the time is 7h; the deformation of the cold rolling is 55%; the temperature of the homogenization treatment is 530°C and the time is 24h; the temperature of the solid solution heat treatment is 510°C and the time is 7h.

[0093] Comparative Example 2

[0094] The present embodiment provides a preparation method of an Al-Mg-Si alloy plate, comprising the following steps:

[0095] The cast ingot is sequentially subjected to homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling to obtain an Al-Mg-Si alloy plate; wherein the chemical composition of the cast ingot is Mg 0.5%, Si 0.55%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, the balance being Al and the mass ratio of Mg and Si being 0.9; the temperature of the aging heat treatment is 155°C and the time is 7h; the deformation of the cold rolling is 55%; the temperature of the homogenization treatment is 530°C and the time is 24h; the temperature of the solid solution heat treatment is 510°C and the time is 7h.

[0096] Comparative Example 3

[0097] The present embodiment provides a preparation method of an Al-Mg-Si alloy plate, comprising the following steps:

[0098] The cast ingot is sequentially subjected to homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling to obtain an Al-Mg-Si alloy plate; wherein the chemical composition of the cast ingot is Mg 0.5%, Si 0.55%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, the balance being Al and the mass ratio of Mg and Si being 0.9; the temperature of the aging heat treatment is 155°C and the time is 7h; the deformation of the cold rolling is 55%; the temperature of the homogenization treatment is 530°C and the time is 24h; the temperature of the solid solution heat treatment is 510°C and the time is 7h.

[0099] Test Example

[0100] 1. The Al-Mg-Si alloy plate of the above embodiments and comparative examples is detected for the following parameters:

[0101] 1) Strength: Universal testing machine tensile test method; see Table 1 for specific results;

[0102] 2) Electrical conductivity: bridge method; see Table 1 for specific results;

[0103] 3) Crack propagation rate curve slope: tension-compression cyclic loading method; see Table 1 for specific results;

[0104] 4) Mg2Si phase and Mg5Si6 phase proportion: Image Pro statistical method; see Table 1 for specific results;

[0105] 5) Electron microscope images of Mg2Si phase and Mg5Si6 phase: The electron microscope images of the Mg2Si phase and the Mg5Si6 phase in the Al-Mg-Si alloy sheet of Example 1 are shown in Figure 1;

[0106] 6) Chemical composition: Fluorescence spectroscopy test method, see Table 2 for specific results.

[0107] 2, Test results

[0108] Table 1 Properties of Al-Mg-Si alloy sheet

[0109] Data analysis:

[0110] From the above table, it can be seen that the Al-Mg-Si alloy sheet of Examples 1-13 of the present application has good electrical conductivity, strength and fatigue resistance.

[0111] Table 2 Chemical composition of Al-Mg-Si alloy sheet (mass percentage of each element (%))

[0112] Note: The mass percentage of each element in Examples 1-13 and Comparative Examples 1-3 is the average value of multiple repeated measurements.

[0113] Data analysis:

[0114] The chemical composition of the Al-Mg-Si alloy sheet of the present application helps to improve the electrical conductivity, strength and fatigue resistance of the Al-Mg-Si alloy sheet.

[0115] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. An Al-Mg-Si alloy sheet, characterized by, The Al-Mg-Si alloy plate comprises, by mass percentage, Mg 0.50%-1.5%, Si 0.49%-0.53%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, and the balance of Al; wherein the mass ratio of Mg to Si is greater than 1.

0.

2. The Al-Mg-Si alloy sheet according to claim 1, characterized in that The mass ratio of Mg to Si is (1.0-3.0):1, and the mass ratio of Mg to Si is not equal to 1.

3. The Al-Mg-Si alloy plate according to claim 1, characterized in that, The microstructure of the Al-Mg-Si alloy plate comprises Mg2Si phase and Mg5Si6 phase; The proportion of the Mg2Si phase in the microstructure of the Al-Mg-Si alloy plate is 0.5%-1%, and the proportion of the Mg5Si6 phase in the microstructure of the Al-Mg-Si alloy plate is 10%-15%.

4. The Al-Mg-Si alloy plate according to claim 1, characterized in that, The strength of the Al-Mg-Si alloy plate is ≥400 MPa, the electrical conductivity is ≥58% IACS, and the crack propagation rate curve slope is ≤3.

0.

5. A method of producing the Al-Mg-Si alloy sheet as claimed in any one of claims 1 to 4, characterized by, The method comprises the following steps: The Al-Mg-Si alloy plate is obtained by sequentially performing homogenization treatment, solid solution heat treatment, aging heat treatment and cold rolling on a cast ingot; The chemical composition of the cast ingot comprises Mg 0.50%-1.5%, Si 0.49%-0.53%, Fe 0.11%-0.18%, La 0.03%-0.05%, B 0.005%-0.02%, impurities ≤0.02%, and the balance of Al, and the mass ratio of Mg to Si is greater than 1.

0.

6. The preparation method according to claim 5, characterized in that, The temperature of the aging heat treatment is 155-165℃, and the time is 5-7h; The deformation amount of the cold rolling is 40%-55%.

7. The preparation method according to claim 5, characterized in that, The temperature of the homogenization treatment is 530-550℃, and the time is 12-24h; And / or, the temperature of the solid solution heat treatment is 510-530℃, and the time is 2-7h.

8. The method of any one of claims 5-7, wherein, The mass ratio of Mg to Si is (1.0-3.0):1, and the mass ratio of Mg to Si is not equal to 1.

9. An apparatus, comprising: The Al-Mg-Si alloy plate according to any one of claims 1-4 or obtained by the preparation method according to any one of claims 5-8.

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