High-toughness aluminum-magnesium-silicon-copper alloy profile and preparation method thereof

Abstract

The invention relates to a preparation method of a high-toughness aluminum-magnesium-silicon-copper alloy profile, which comprises the following elements in percentage by mass: 1.50 to 1.70 percent of Si, less than or equal to 0.20 percent of Fe, 0.80 to 1.00 percent of Cu, 0.55 to 0.65 percent of Mn, 1.00 to 1.20 percent of Mg, 0.15 to 0.25 percent of Cr, 0.15 to 0.25 percent of Zn, 0.15 to 0.25 percent of Zr, 0.01 to 0.05 percent of Ti, 0.08 to 0.15 percent of V, 1.4 to 1.7 percent of Mg / Si and the balance of Al. The total content of each inevitable impurity element is lower than 0.05%, the total content of the inevitable impurity elements is smaller than 0.1%, the balance is Al, and the sum of the total content of the inevitable impurity elements is 100%. The preparation method comprises the steps of burdening, smelting, degassing and filtering, casting, soaking, sawing and turning, extruding, solid solution quenching, stretching, two-stage aging and the like. The high-performance aluminum alloy material has excellent tensile strength, yield strength and elongation, is good in extrudable performance, meets the requirements of carrying traffic vehicle body structural components and the like for high-performance aluminum alloy materials, and is stable in preparation process and suitable for large-scale production.

Description

Technical Field

[0001] The invention relates to the technical field of alloy smelting, and more particularly to a method for preparing a high-strength and tough aluminum-magnesium-silicon-copper alloy profile. Background Art

[0002] Aluminum-magnesium-silicon-aluminum alloy has the characteristics of high strength, high toughness, corrosion resistance, light weight, low cost and recyclability. The use of high-performance aluminum alloy is not only conducive to reducing fuel consumption and comfort, but also can better protect the driver's driving safety. At present, transportation lightweight materials are still mainly traditional alloys such as 6082, 6061, and 6005. With the development of lightweight materials, the above materials can no longer meet the increasingly high performance requirements in the field of transportation lightweighting. In order to meet the urgent demand for high-performance lightweight components, it is urgent to develop alloy materials with higher strength and better comprehensive performance.

[0003] Invention patent CN116083825B discloses a method for preparing a high-strength and high-toughness textured aluminum-magnesium-silicon alloy. The Al-Mg-Si aluminum alloy with ordinary composition is subjected to high-temperature smelting, high-temperature solution treatment, cyclic hot extrusion and low-temperature short-time aging to improve the strength and toughness of the Al-Mg-Si aluminum alloy material, and obtains a tensile strength of 380MPa. This performance meets the requirements of vehicle anti-collision guardrails, but cannot meet the requirements of heavy-loaded structural beams; Invention patent CN114086041B discloses a high-strength and high-toughness aluminum alloy and its preparation method, which is subjected to high-pressure water atomization, sintering, etc. The preparation method of powder metallurgy can obtain a high-strength aluminum alloy material with a tensile strength of 450MPa, but the process is complicated, the product size is limited, and it is not suitable for large-scale production; the invention patent CN114058889A introduces a method for improving the mechanical properties of aluminum alloys by adding rare earth elements, mainly through the process of adding rare earth elements Ce, La and Sc twice refining, to obtain a tensile strength of 355MPa, a yield strength of 282MPa, and an elongation of 10.9%, but its comprehensive mechanical properties still cannot meet the performance requirements of the structural profile of the transportation vehicle body. In addition, improving the performance by adding rare earth elements is complicated in practice.

[0004] Therefore, it is of great significance to develop an aluminum alloy with good mechanical strength and suitable for bearing large loads. Summary of the invention

[0005] In view of the above-mentioned technical problems, the purpose of the present invention is to provide a method for preparing a high-strength and tough aluminum-magnesium-silicon-copper alloy profile, so that the material exhibits good mechanical strength and processability, and is suitable for application scenarios of aluminum alloy structural parts that require a large load-bearing capacity, especially aluminum alloy structural parts of transportation vehicle bodies subject to tensile stress.

[0006] To achieve the above object, the present invention adopts the following scheme:

[0007] The invention discloses a preparation method of a high-strength and tough aluminum-magnesium-silicon-copper alloy profile, comprising: the aluminum alloy material comprises the following element components by mass percentage: Si: 1.50-1.70%, Fe≤0.20%, Cu: 0.80-1.00%, Mn: 0.55-0.65%, Mg: 1.00-1.20%, Cr: 0.15-0.25%, Zn: 0.15-0.25%, Zr: 0.15-0.25%, Ti: 0.01-0.05%, V: 0.08-0.15%, Mg / Si is controlled at 1.4-1.7; the Cu content is controlled at 0.3-0.35 times the total amount of Mg and Si, the total content of each unavoidable impurity element is less than 0.05%, and the total amount is less than 0.1%, and the remaining component is Al, and the sum of the total amounts of the components is 100%.

[0008] A method for preparing a high-strength and tough aluminum-magnesium-silicon-copper alloy profile comprises the following steps:

[0009] S1, ingredients, smelting;

[0010] S2, degassing and filtering;

[0011] S3, casting;

[0012] S4, heat treatment;

[0013] S5, sawing, car skin;

[0014] S6, extrusion;

[0015] S7, solution quenching: After extrusion molding, the extruded alloy profile is immediately sent to a vertical quenching furnace for water quenching, and the quenching medium is deionized water;

[0016] S8, stretching;

[0017] S9, double-stage aging treatment: the stretched alloy profile is subjected to primary aging treatment and secondary aging treatment.

[0018] Preferably, the Si is in the form of industrial crystalline silicon, Al-Si or Mg-Si master alloy, Mn and Zr are in the form of aluminum master alloy, and Ti is in the form of AlTi or AlTiB master alloy as grain refining additives.

[0019] Preferably, in S1, the ingredients are mixed and heated to 760-780° C. to melt the materials, and the temperature is kept for 5-7 hours.

[0020] Preferably, in S3, the aluminum liquid after degassing and filtration is poured and cooled to room temperature to obtain a round ingot with a diameter of 178 to 254 mm, wherein the casting temperature is 695 to 740°C.

[0021] Preferably, in said S4, after the ingot is placed in a soaking furnace for heating and insulation, a soaking heat treatment is performed, and the insulation temperature is 545-555° C. and the insulation time is 5-10 hours.

[0022] Preferably, in S6, the processed ingot is preheated in a permanent magnet heating furnace, and the ingot is extruded into shape after preheating. The first section of the ingot is extruded using an alloy as a guide ingot. The preheating temperature in the permanent magnet heating furnace is 510-520°C, the time is 120s, the extrusion ratio ranges from 30 to 60, and the extrusion speed is 2.5-3.0mm / s. The first section of the ingot is extruded using an alloy with an ingot yield strength of 100MPa to 120MPa as a guide ingot.

[0023] Preferably, the solution temperature in S7 is 545-550°C, and the quenching cooling rate is 370-400°C / min.

[0024] Preferably, the elongation rate of the alloy profile in S8 is controlled to be 0.5% to 1.5% when straightening.

[0025] Preferably, in the two-stage aging treatment in S9, the first-stage aging is at a temperature of 85-95° C. and is kept warm for 4-6 hours; the second-stage aging is at a temperature of 170-180° C. and is kept warm for 8-10 hours.

[0026] The present invention discloses the following technical effects:

[0027] 1. In the aluminum alloy of the present invention, Si, Mg and Cu work together to form Mg 2 Si phase and Al-Cu-Mg-Si phase intermetallic compounds, thereby significantly enhancing the precipitation strengthening effect of the alloy; at the same time, adding an appropriate amount of Zr component can increase the recrystallization temperature during solution treatment, refine the grains, and improve the strength of the metal by refining the grain size to achieve fine grain strengthening; adding Zn elements can effectively increase the plasticity and toughness of the alloy;

[0028] 2. The aluminum alloy prepared by the present invention has excellent performance and meets the requirements of large-scale production. The tensile strength reaches more than 450Mpa, the yield strength reaches more than 400Mpa, and the elongation reaches more than 13%. It has excellent performance and achieves good extrudability, which greatly meets the application requirements of materials in the load-bearing structure of transportation vehicles;

[0029] 3. The alloy elements used in the present invention are all common and relatively low in cost, which reduces the cost of materials and is more suitable for large-scale manufacturing. At the same time, the stable preparation process reduces the scrap rate and rework rate in the production process, improves production efficiency, and has significant cost advantages while ensuring high performance, which is more conducive to promotion and use in the market, and provides an economically feasible solution for the strong quantitative development of the transportation industry;

[0030] 4. The high-strength and tough aluminum-magnesium-silicon-copper alloy profile of the present invention has outstanding environmental benefits. Since aluminum alloy has the recyclable property, the aluminum-magnesium-silicon-copper alloy profile can be conveniently recycled and reused after being scrapped, which reduces the demand for mining new resources, reduces resource consumption, and reduces the pollution of waste metals to the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0032] Figure 1 A flow chart is prepared for the present invention;

[0033] Figure 2 This is a comparison table of performance item test results in Examples 1-4 of the present invention;

[0034] Figure 3 The following is a comparison table of the test results of the performance items in Comparative Examples 1-5 of the present invention. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] Example 1

[0038] Refer to the attached Figure 1-3, a method for preparing a high-strength and tough aluminum-magnesium-silicon-copper alloy profile, comprising: the aluminum alloy material contains the following elemental components by mass percentage: Si: 1.70%, Fe: 0.15%, Cu: 1.00%, Mn: 0.65%, Mg: 1.20%, Cr: 0.25%, Zn: 0.15%, Zr: 0.25%, Ti: 0.05%, V: 0.08%; the total content of each unavoidable impurity element is less than 0.05%, and the total amount is less than 0.1%, and the remaining component is Al, and the sum of the total amounts of each component is 100%.

[0039] The preparation method of high-strength and tough aluminum-magnesium-silicon-copper alloy profile specifically comprises the following steps:

[0040] S1. Batching and smelting: Batching the aluminum alloy material according to the percentage, wherein Si is in the form of industrial crystalline silicon, Al-Si or Mg-Si master alloy, Mn, Zr, and aluminum-containing master alloy, and Ti is added in the form of AlTiB master alloy as a grain refining additive; after mixing, heating to 780° C. to melt the material and keeping the temperature for 7 hours;

[0041] S2, degassing and filtering: degas the molten alloy liquid, and then filter the insoluble matter to obtain aluminum liquid;

[0042] S3, casting: pouring the degassed and filtered aluminum liquid, cooling it to room temperature, and obtaining a round ingot with a diameter of 254 mm, wherein the casting temperature is 740°C;

[0043] S4, soaking treatment: placing the ingot in a soaking furnace for heating and insulation, the insulation temperature is 550°C, the insulation time is 10h, and the soaking heat treatment is performed;

[0044] S5, sawing and lathing: the ingot after the soaking treatment is transported to the sawing machine and lathe for sawing and lathing;

[0045] S6, extrusion: preheat the processed ingot in a permanent magnet heating furnace, the preheating temperature is 520°C, the time is 120s, and the ingot is extruded after preheating, the extrusion ratio range is 55, the extrusion speed is 2.5mm / s, and the first section of the ingot is extruded using an alloy with an ingot yield strength of 120MPa as a guide ingot;

[0046] S7, solution quenching: After the ingot is extruded, the extruded alloy profile is immediately sent to a vertical quenching furnace for water quenching. The solution temperature is 540°C, the quenching medium is deionized water, and the quenching cooling rate is 390°C / min;

[0047] S8, stretching: when the alloy profile is straightened, the stretching rate is controlled to be 1.2%;

[0048] S9. Double-stage aging treatment: The stretched alloy profiles are subjected to double-stage aging treatment, the first-stage aging treatment is at a temperature of 85°C and is kept warm for 6 hours; the second-stage aging treatment is at a temperature of 175°C and is kept warm for 10 hours.

[0049] Example 2

[0050] The invention discloses a method for preparing a high-strength and tough aluminum-magnesium-silicon-copper alloy profile, comprising: the aluminum alloy material comprises the following elemental components by mass percentage: Si: 1.50%, Fe: 0.11%, Cu: 0.80%, Mn: 0.62%, Mg: 1.00%, Cr: 0.16%, Zn: 0.25%, Zr: 0.15%, Ti: 0.05%, V: 0.08%; the total content of each unavoidable impurity element is less than 0.05%, and the total amount is less than 0.1%, and the remaining component is Al, and the sum of the total amounts of each component is 100%.

[0051] The preparation method of high-strength and tough aluminum-magnesium-silicon-copper alloy profile specifically comprises the following steps:

[0052] S1. Batching and smelting: Batching the aluminum alloy material according to the percentage, wherein Si is in the form of industrial crystalline silicon, Al-Si or Mg-Si master alloy, Mn, Zr, and aluminum-containing master alloy, and Ti is added in the form of AlTiB master alloy as a grain refining additive; after mixing, heating to 760° C. to melt the material and keeping the temperature for 5 hours;

[0053] S2, degassing and filtering: degas the molten alloy liquid, and then filter the insoluble matter to obtain aluminum liquid;

[0054] S3, casting: pouring the degassed and filtered aluminum liquid, cooling it to room temperature, and obtaining a round ingot with a diameter of 178 mm, wherein the casting temperature is 695-740° C.;

[0055] S4, soaking treatment: placing the ingot in a soaking furnace for heating and insulation, the insulation temperature is 550°C, the insulation time is 5h, and the soaking heat treatment is performed;

[0056] S5, sawing and lathing: the ingot after the soaking treatment is transported to the sawing machine and lathe for sawing and lathing;

[0057] S6, extrusion: preheat the processed ingot in a permanent magnet heating furnace, the preheating temperature is 520°C, the time is 120s, and the ingot is extruded after preheating, the extrusion ratio range is 35, the extrusion speed is 3.0mm / s, and the first section of the ingot is extruded using an alloy with an ingot yield strength of 110MPa as a guide ingot;

[0058] S7, solution quenching: After the ingot is extruded, the extruded alloy profile is immediately sent to a vertical quenching furnace for water quenching. The solution temperature is 540°C, the quenching medium is deionized water, and the quenching cooling rate is 370°C / min;

[0059] S8, stretching: when the alloy profile is straightened, the stretching rate is controlled to be 0.5%;

[0060] S9. Double-stage aging treatment: The stretched alloy profiles are subjected to double-stage aging treatment, the first-stage aging treatment is at a temperature of 90°C and is kept warm for 4 hours; the second-stage aging treatment is at a temperature of 175°C and is kept warm for 8 hours.

[0061] Example 3

[0062] The invention discloses a method for preparing a high-strength and tough aluminum-magnesium-silicon-copper alloy profile, comprising: the aluminum alloy material comprises the following elemental components by mass percentage: Si: 1.60%, Fe: 0.12%, Cu: 0.80%, Mn: 0.62%, Mg: 1.10%, Cr: 0.20%, Zn: 0.20%, Zr: 0.20%, Ti: 0.03%, V: 0.10%; the total content of each unavoidable impurity element is less than 0.05%, and the total amount is less than 0.1%, and the remaining component is Al, and the sum of the total amounts of each component is 100%.

[0063] The preparation method of high-strength and tough aluminum-magnesium-silicon-copper alloy profile specifically comprises the following steps:

[0064] S1. Ingredients and smelting: Ingredients are prepared according to the percentage of the aluminum alloy material, wherein Si is in the form of industrial crystalline silicon, Al-Si or Mg-Si master alloy, Mn, Zr, aluminum-containing master alloy, and Ti is in the form of AlTiB 0.5 Add in the form of master alloy as a grain refining additive; after mixing, heat to 780℃ to melt the material and keep it warm for 7h;

[0065] S2, degassing and filtering: degas the molten alloy liquid, and then filter the insoluble matter to obtain aluminum liquid;

[0066] S3, casting: pouring the degassed and filtered aluminum liquid, cooling it to room temperature, and obtaining a round ingot with a diameter of 254 mm, wherein the casting temperature is 740°C;

[0067] S4, soaking treatment: placing the ingot in a soaking furnace for heating and insulation, the insulation temperature is 550°C, the insulation time is 8h, and the soaking heat treatment is performed;

[0068] S5, sawing and lathing: the ingot after the soaking treatment is transported to the sawing machine and lathe for sawing and lathing;

[0069] S6, extrusion: preheat the processed ingot in a permanent magnet heating furnace, the preheating temperature is 520°C, the time is 120s, and the ingot is extruded after preheating, the extrusion ratio range is 35, the extrusion speed is 3.0mm / s, and the first section of the ingot is extruded using an alloy with an ingot yield strength of 110MPa as a guide ingot;

[0070] S7, solution quenching: After the ingot is extruded, the extruded alloy profile is immediately sent to a vertical quenching furnace for water quenching. The solution temperature is 540°C, the quenching medium is deionized water, and the quenching cooling rate is 400°C / min;

[0071] S8, stretching: when the alloy profile is straightened, the stretching rate is controlled to be 1.0%;

[0072] S9. Double-stage aging treatment: The stretched alloy profiles are subjected to double-stage aging treatment, the first-stage aging treatment is at a temperature of 90°C and is kept warm for 6 hours; the second-stage aging treatment is at a temperature of 175°C and is kept warm for 10 hours.

[0073] Example 4

[0074] The invention discloses a method for preparing a high-strength and tough aluminum-magnesium-silicon-copper alloy profile, comprising: the aluminum alloy material comprises the following elemental components by mass percentage: Si: 1.60%, Fe: 0.13%, Cu: 0.90%, Mn: 0.60%, Mg: 1.1%, Cr: 0.20%, Zn: 0.20%, Zr: 0.25%, Ti: 0.03%, V: 0.15%; the total content of each unavoidable impurity element is less than 0.05%, and the total amount is less than 0.1%, and the remaining component is Al, and the sum of the total amounts of each component is 100%.

[0075] The preparation method of high-strength and tough aluminum-magnesium-silicon-copper alloy profile specifically comprises the following steps:

[0076] S1. Ingredients and smelting: Ingredients are prepared according to the percentage of the aluminum alloy material, wherein Si is in the form of industrial crystalline silicon, Al-Si or Mg-Si master alloy, Mn, Zr, aluminum-containing master alloy, and Ti is in the form of AlTiB 0.5 Add in the form of master alloy as a grain refining additive; after mixing, heat to 780℃ to melt the material and keep it warm for 7h;

[0077] S2, degassing and filtering: degas the molten alloy liquid, and then filter the insoluble matter to obtain aluminum liquid;

[0078] S3, casting: pouring the degassed and filtered aluminum liquid, cooling it to room temperature, and obtaining a round ingot with a diameter of 254 mm, wherein the casting temperature is 740°C;

[0079] S4, soaking treatment: placing the ingot in a soaking furnace for heating and insulation, the insulation temperature is 550°C, the insulation time is 8h, and the soaking heat treatment is performed;

[0080] S5, sawing and lathing: the ingot after the soaking treatment is transported to the sawing machine and lathe for sawing and lathing;

[0081] S6, extrusion: preheat the processed ingot in a permanent magnet heating furnace, the preheating temperature is 520°C, the time is 120s, and the ingot is extruded after preheating, the extrusion ratio range is 30, the extrusion speed is 3.0mm / s, and the first section of the ingot is extruded using an alloy with an ingot yield strength of 120MPa as a guide ingot;

[0082] S7, solution quenching: After the ingot is extruded, the extruded alloy profile is immediately sent to a vertical quenching furnace for water quenching. The solution temperature is 540°C, the quenching medium is deionized water, and the quenching cooling rate is 400°C / min;

[0083] S8, stretching: when the alloy profile is straightened, the stretching rate is controlled to be 1.0%;

[0084] S9. Double-stage aging treatment: The stretched alloy profiles are subjected to double-stage aging treatment, the first-stage aging treatment is at a temperature of 90°C and is kept warm for 6 hours; the second-stage aging treatment is at a temperature of 175°C and is kept warm for 10 hours.

[0085] Comparative Example 1

[0086] The aluminum alloy material contains the following elemental components in percentage by mass: Si: 1.30%, Fe: 0.15%, Cu≤0.10%, Mn: 0.65%, Mg: 1.20%, Cr: 0.25%, Zn: 0.20%, Zr: 0.25%, Ti: 0.05%, V: 0.08%; the total content of each unavoidable impurity element is less than 0.05%, and the total amount is less than 0.1%, the remaining component is Al, the sum of the total amounts of each component is 100%, and the other steps are the same as those in Example 1.

[0087] Comparative Example 2

[0088] The aluminum alloy material contains the following elemental components in percentage by mass: Si: 1.00%, Fe: 0.15%, Cu: 1.00%, Mn: 0.65%, Mg: 1.20%, Cr: 0.25%, Zn: 0.15%, Zr: 0.25%, Ti: 0.05%, V: 0.08%; the total content of each unavoidable impurity element is less than 0.05%, and the total amount is less than 0.1%, the remaining component is Al, the sum of the total amounts of each component is 100%, and the other steps are the same as those in Example 1.

[0089] Comparative Example 3

[0090] The aluminum alloy material contains the following elemental components in percentage by mass: Si: 1.70%, Fe: 0.15%, Cu: 1.00%, Mn: 0.65%, Mg: 0.60%, Cr: 0.23%, Zn: 0.15%, Zr: 0.25%, Ti: 0.05%, V: 0.08%; the total content of each unavoidable impurity element is less than 0.05%, and the total amount is less than 0.1%, the remaining component is Al, the sum of the total amounts of each component is 100%, and the other steps are the same as those in Example 1.

[0091] Comparative Example 4

[0092] A high-strength and toughness aluminum alloy profile and a preparation method thereof. In the aging treatment, the stretched profile is subjected to a single-stage aging treatment, the single-stage aging temperature is 175° C., and the heat preservation is 16 hours. The other steps are the same as those in Example 1.

[0093] Comparative Example 5

[0094] A high-strength and toughness aluminum alloy profile and a preparation method thereof, wherein online water quenching is adopted during the solid solution quenching process, and other steps are the same as those in Example 1.

[0095] The aluminum alloy profiles obtained in Examples 1-4 were tested for tensile strength, yield strength and elongation. Figure 2 As shown, the present invention can prepare an aluminum alloy profile with excellent comprehensive mechanical properties of tensile strength of more than 450MPa, yield strength of more than 400MPa, and elongation of 13% or more; the aluminum alloy profiles finally obtained in Comparative Examples 1-5 are tested for performance items of tensile strength, yield strength and elongation, as shown in FIG. Figure 3 As shown in the comparative example, when the magnesium-silicon content is reduced, Mg can not be provided during the aging precipitation process. 2 Si phase, thus affecting the strength improvement of aluminum alloy profiles. When the Cu content is very low, the strengthening effect in the alloy is mainly achieved through the precipitation strengthening of Mg and Si. With the addition of Cu element content, Cu will be completely dissolved into the aluminum matrix during the homogenization heat treatment process, and form Al-Cu-Mg-Si phase with a certain amount of Mg and Si elements during the precipitation process, which can greatly improve the strength of the alloy. At the same time, the addition of Cu can also reduce the rate of natural aging of aluminum alloys, thereby reducing the adverse effects of strength reduction caused by aging hysteresis. Since the improvement of the comprehensive mechanical properties of alloy materials is a comprehensive manifestation of the synergistic effect of phase precipitation strengthening, a suitable aging heat treatment process can improve the strength and toughness of aluminum alloys.

[0096] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0097] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A high-strength and tough aluminum-magnesium-silicon-copper alloy profile, characterized in that: include: The aluminum alloy material contains the following elemental components in percentage by mass: Si: 1.50-1.70%, Fe≤0.20%, Cu: 0.80-1.00%, Mn: 0.55-0.65%, Mg: 1.00-1.20%, Cr: 0.15-0.25%, Zn: 0.15-0.25%, Zr: 0.15-0.25%, Ti: 0.01-0.05%, V: 0.08-0.15%, Mg / Si is controlled at 1.4-1.7; the Cu content is controlled at 0.3-0.35 times the total amount of Mg and Si, the total content of each unavoidable impurity element is less than 0.05%, and the total amount is less than 0.1%, and the remaining component is Al, and the sum of the total amounts of each component is 100%.

2. A method for preparing a high-strength and tough aluminum-magnesium-silicon-copper alloy profile according to claim 1, characterized in that: The following steps are involved: S1, ingredients, smelting; S2, degassing and filtering; S3, casting; S4, heat treatment; S5, sawing, car skin; S6, extrusion; S7, solution quenching: After extrusion molding, the extruded alloy profile is immediately sent to a vertical quenching furnace for water quenching, and the quenching medium is deionized water; S8, stretching; S9, double-stage aging treatment: the stretched alloy profile is subjected to primary aging treatment and secondary aging treatment.

3. The method for preparing a high-strength and tough aluminum-magnesium-silicon-copper alloy profile according to claim 1, characterized in that: The Si is in the form of industrial crystalline silicon, Al-Si or Mg-Si master alloy, Mn and Zr are in the form of aluminum-containing master alloy, and Ti is in the form of AlTi or AlTiB master alloy, which are used as grain refining additives.

4. The method for preparing a high-strength and tough aluminum-magnesium-silicon-copper alloy profile according to claim 2, characterized in that: In S1, the ingredients are mixed and heated to 760-780° C. to melt the materials, and the temperature is kept for 5-7 hours.

5. The method for preparing a high-strength and tough aluminum-magnesium-silicon-copper alloy profile according to claim 2, characterized in that: In S3, the aluminum liquid after degassing and filtration is poured and cooled to room temperature to obtain a round ingot, wherein the diameter of the round ingot is 178 to 254 mm and the casting temperature is 695 to 740°C.

6. The method for preparing a high-strength and tough aluminum-magnesium-silicon-copper alloy profile according to claim 2, characterized in that: In S4, the ingot is placed in a soaking furnace for heating and insulation, and then subjected to a soaking heat treatment, the insulation temperature being 545-555° C. and the insulation time being 5-10 hours.

7. The method for preparing a high-strength and tough aluminum-magnesium-silicon-copper alloy profile according to claim 2, characterized in that: In the S6, the processed ingot is preheated in a permanent magnet heating furnace, and the ingot is extruded after preheating. The first section of the ingot is extruded using an alloy as a guide ingot. The preheating temperature in the permanent magnet heating furnace is 510-520°C, the time is 120s, the extrusion ratio ranges from 30 to 60, and the extrusion speed is 2.5-3.0mm / s. The first section of the ingot is extruded using an alloy with an ingot yield strength of 100MPa to 120MPa as a guide ingot.

8. The method for preparing a high-strength and tough aluminum-magnesium-silicon-copper alloy profile according to claim 2, characterized in that: The solution temperature in S7 is 545-550°C, and the quenching cooling rate is 370-400°C / min.

9. The method for preparing a high-strength and tough aluminum-magnesium-silicon-copper alloy profile according to claim 2, characterized in that: When the alloy profile in S8 is straightened, the elongation rate is controlled to be 0.5% to 1.5%.

10. The method for preparing a high-strength and tough aluminum-magnesium-silicon-copper alloy profile according to claim 2, characterized in that: In the two-stage aging treatment in S9, the first-stage aging is at a temperature of 85-95° C. and is kept warm for 4-6 hours; the second-stage aging is at a temperature of 170-180° C. and is kept warm for 8-10 hours.

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