A 6182-T7 aluminum alloy and its preparation method and application

Abstract

The present invention provides a 6182-T7 aluminum alloy and a preparation method and application thereof. The preparation method of the 6182-T7 aluminum alloy of the present invention comprises the steps of aluminum rod melting and casting, homogenization treatment, preheating, extrusion, solution treatment, straightening, forging, artificial aging treatment, etc., wherein two-stage aging is adopted during the artificial aging treatment: the first stage aging is at 175±5°C, and the holding time is 6-6.5h; the second stage aging is at 205±5°C, and the holding time is 6-6.5h. The 6182-T7 aluminum alloy prepared by the present invention meets the following performance requirements: tensile strength ≥ 280 MPa, yield strength: 230-280 MPa, elongation ≥ 10%, and bending angle ≥ 70°; after short-term stability at 190±5°C*45min, the following requirements are met: tensile strength ≥ 280 MPa, yield strength: 230-280 MPa, elongation ≥ 10%, and bending angle ≥ 70°; after long-term stability at 120±5°C*500h, the following requirements are met: tensile strength ≥ 280 MPa, yield strength: 230-280 MPa, elongation ≥ 10%, and bending angle ≥ 70°. The prepared 6182-T7 aluminum alloy is used to prepare an aluminum alloy universal joint bracket for a vehicle, and can meet the performance requirements of customers for the 6182 bracket.

Description

Technical Field

[0001] The invention belongs to the technical field of deformed aluminum alloy material preparation, and specifically relates to a 6182-T7 aluminum alloy and a preparation method and application thereof. Background Art

[0002] With the requirements for energy saving, environmental protection, lightweight and high mobility of automobiles, the lightweight of automobiles has developed rapidly. Aluminum alloy has the characteristics of moderate strength, light weight and easy forming, which is suitable for lightweight design of automobiles. Considering the strength, plasticity and safety, the automobile universal joint bracket needs to be made of 6182 aluminum alloy. At present, customers have the following performance requirements for the 6182 bracket: T7 performance requirements after forging: tensile strength ≥280MPa, yield strength: 230-280MPa, elongation ≥10%, bending angle ≥70°; after short-term stability at 190±5℃*45min, the following requirements are met: tensile strength ≥280MPa, yield strength: 230-280MPa, elongation ≥10%, bending angle ≥70°; after long-term stability at 120±5℃*500h, the following requirements are met: tensile strength ≥280MPa, yield strength: 230-280MPa, elongation ≥10%, bending angle ≥70°. Currently, the existing aluminum alloys cannot meet the above requirements, and it is necessary to develop a new 6182 alloy preparation method to meet the above applications. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a 6182-T7 aluminum alloy and its preparation method and application. The 6182-T7 aluminum alloy prepared by the present invention can meet the following performance requirements: tensile strength ≥ 280MPa, yield strength: 230-280MPa, elongation ≥ 10%, bending angle ≥ 70°; after short-term stability at 190±5℃*45min, it meets the following requirements: tensile strength ≥ 280MPa, yield strength: 230-280MPa, elongation ≥ 10%, bending angle ≥ 70°; after long-term stability at 120±5℃*500h, it meets the following requirements: tensile strength ≥ 280MPa, yield strength: 230-280MPa, elongation ≥ 10%, bending angle ≥ 70°. The prepared 6182-T7 aluminum alloy is used to prepare aluminum alloy universal joint brackets for vehicles, which can meet the performance requirements of customers for 6182 brackets.

[0004] In order to achieve the above technical objectives, the technical solution adopted by the embodiment of the present invention is:

[0005] In a first aspect, an embodiment of the present invention provides a method for preparing a 6182-T7 aluminum alloy, comprising the following steps:

[0006] (1) Aluminum rod casting: Prepare the raw materials according to the alloying element composition of 6182 aluminum alloy and cast them into cast rods;

[0007] (2) Homogenization treatment: the cast rod obtained in step (1) is kept at 510±5°C for 9-10 hours, and after homogenization treatment, it is taken out of the furnace and water-cooled to room temperature;

[0008] (3) Preheating: heating the homogenized cast rod obtained in step (2) to 490-520°C, with a temperature gradient of 10-30°C between the head and tail of the cast rod; heating the extrusion die to 470-490°C; heating the die barrel to 430-440°C;

[0009] (4) Extrusion: using an extruder to extrude the preheated cast rod in step (3) at a speed of 4-5 m / min;

[0010] (5) Solution treatment: the product obtained in step (4) is subjected to online solution treatment, and an online water cooling method is adopted during the online solution treatment;

[0011] (6) Straightening: straightening the product obtained in step (5);

[0012] (7) forging the product obtained in step (6), and cooling it with water after forging;

[0013] (8) Artificial aging treatment: The forgings of the product obtained in step (7) are subjected to artificial aging treatment, and the aging treatment is divided into two levels: the first level is aging at 175±5°C, and the holding time is 6-6.5 h; the second level is aging at 205±5°C, and the holding time is 6-6.5 h.

[0014] Furthermore, the element composition of the 6182 aluminum alloy includes, by mass percentage, Si: 0.95%-1.1%, Fe≤0.25%, Cu≤0.1%, Mn≤0.8-0.9%, Mg: 0.9%-1.05%, Cr≤0.25%, Zn≤0.20%, Ti≤0.10%, Zr≤0.08-0.15%, other single elements≤0.05%, other impurity elements total≤0.15%, Al: balance.

[0015] In a second aspect, an embodiment of the present invention provides a 6182-T7 aluminum alloy, which is prepared by the preparation method of the first aspect.

[0016] Furthermore, the 6182-T7 aluminum alloy meets the following performance requirements: tensile strength ≥ 280 MPa, yield strength: 230-280 MPa, elongation ≥ 10%, bending angle ≥ 70°; after short-term stability at 190±5°C*45min, the following requirements are met: tensile strength ≥ 280 MPa, yield strength: 230-280 MPa, elongation ≥ 10%, bending angle ≥ 70°; after long-term stability at 120±5°C*500h, the following requirements are met: tensile strength ≥ 280 MPa, yield strength: 230-280 MPa, elongation ≥ 10%, bending angle ≥ 70°.

[0017] In a third aspect, an embodiment of the present invention provides an application of a 6182-T7 aluminum alloy, wherein the 6182-T7 aluminum alloy described in the second aspect is used to prepare an aluminum alloy universal joint bracket for a vehicle.

[0018] The technical solution provided by the embodiment of the present invention has the following beneficial effects:

[0019] The 6182-T7 aluminum alloy preparation method of the present invention adopts a two-stage aging process, wherein the first stage and the second stage aging can be performed separately, and both can realize the combined furnace production of other products to achieve the maximum production efficiency of energy.

[0020] The 6182-T7 aluminum alloy prepared by the present invention meets the following performance requirements: tensile strength ≥ 280 MPa, yield strength: 230-280 MPa, elongation ≥ 10%, bending angle ≥ 70°; after short-term stability at 190±5°C*45min, the following requirements are met: tensile strength ≥ 280 MPa, yield strength: 230-280 MPa, elongation ≥ 10%, bending angle ≥ 70°; after long-term stability at 120±5°C*500h, the following requirements are met: tensile strength ≥ 280 MPa, yield strength: 230-280 MPa, elongation ≥ 10%, bending angle ≥ 70°. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0022] Example 1

[0023] A method for preparing 6182-T7 aluminum alloy comprises the following steps:

[0024] (1) Aluminum rod casting: The raw materials are prepared according to the alloying element composition of 6182 aluminum alloy and cast into cast rods. The element composition of 6182 aluminum alloy includes, by mass percentage, Si: 1.022%, Fe: 0.219%, Cu: 0.045%, Mn: 0.862%, Mg: 0.951%, Cr: 0.136%, Zn: 0.0024%, Ti: 0.037%, Zr: 0.119%, other single elements ≤ 0.05%, other impurity elements total ≤ 0.15%, Al: balance.

[0025] (2) Homogenization treatment: the cast rod obtained in step (1) is kept at 510±5°C for 9.5 hours, and after homogenization treatment, it is taken out of the furnace and water-cooled to room temperature;

[0026] (3) Preheating: heating the homogenized cast rod obtained in step (2) to a temperature of 490-520°C, with a temperature gradient of 10-30°C between the head and tail of the cast rod; heating the extrusion die to a temperature of 470-490°C; heating the die barrel to a temperature of 430-440°C;

[0027] (4) Extrusion: The cast rod preheated in step (3) is extruded by an extruder at a speed of 4.5 m / min;

[0028] (5) Solution treatment: the product obtained in step (4) is subjected to online solution treatment, wherein the online solution treatment is performed by online water cooling;

[0029] (6) Straightening: straightening the product obtained in step (5);

[0030] (7) forging the product obtained in step (6), and cooling it with water after forging;

[0031] (8) Artificial aging treatment: The forgings of the product obtained in step (7) are subjected to artificial aging treatment, and the aging treatment is divided into two levels: the first level is aging at 170°C, and the holding time is 6 hours; the second level is aging at 200°C, and the holding time is 6 hours.

[0032] Example 2

[0033] A method for preparing 6182-T7 aluminum alloy, which is different from the preparation method in Example 1 in that, in this embodiment, the artificial aging process for the forging of the product obtained in step (7) is: the first stage aging is 175°C, and the holding time is 6 hours; the second stage aging is 205°C, and the holding time is 6 hours, to obtain a final product.

[0034] Example 3

[0035] A method for preparing 6182-T7 aluminum alloy, which is different from the preparation method in Example 1 in that, in this embodiment, the artificial aging process for the forging of the product obtained in step (7) is: the first stage aging is 175°C, and the holding time is 6.5h; the second stage aging is 205°C, and the holding time is 6.5h, to obtain a final product.

[0036] Example 4

[0037] A method for preparing 6182-T7 aluminum alloy, which is different from the preparation method in Example 1 in that, in this embodiment, the artificial aging process for the forging of the product obtained in step (7) is: the first stage aging is 180°C, and the holding time is 6.5h; the second stage aging is 210°C, and the holding time is 6.5h, to obtain a final product.

[0038] Comparative Example 1

[0039] A method for preparing 6182 aluminum alloy, which is different from the preparation method in Example 1 in that, in this comparative example, the artificial aging process for the forging of the product obtained in step (7) is: the first stage aging is 169° C., and the holding time is 6.5 h; the second stage aging is 205° C., and the holding time is 6.5 h, to obtain a final product.

[0040] Comparative Example 2

[0041] A method for preparing 6182 aluminum alloy, which is different from the preparation method in Example 1 in that, in this comparative example, the artificial aging process for the forging of the product obtained in step (7) is: the first stage aging is 169° C., and the holding time is 6.5 h; the second stage aging is 210° C., and the holding time is 6.5 h, to obtain a final product.

[0042] Comparative Example 3

[0043] A method for preparing 6182 aluminum alloy, which is different from the preparation method in Example 1 in that, in this comparative example, the artificial aging process for the forging of the product obtained in step (7) is: the first stage aging is 181° C., and the holding time is 6 h; the second stage aging is 200° C., and the holding time is 6 h, to obtain a final product.

[0044] Comparative Example 4

[0045] A method for preparing 6182 aluminum alloy, which is different from the preparation method in Example 1 in that, in this comparative example, the artificial aging process for the forging of the product obtained in step (7) is: the first stage aging is 181° C., and the holding time is 6 h; the second stage aging is 205° C., and the holding time is 6 h, to obtain a final product.

[0046] The tensile properties, bending properties, and tensile properties and bending properties after short-cycle thermal stabilization of the products obtained in Examples 1-4 and Comparative Examples 1-4 were tested, and the test results are shown in Table 1.

[0047] Table 1 Comparison of relevant properties of aluminum alloy products of Examples 1-4 and Comparative Examples 1-4

[0048]

[0049] The tensile properties and bending properties of the aluminum alloy products of Examples 1-4 and Comparative Examples 1-4 after long-term thermal stabilization were tested, and the test results are shown in Table 2.

[0050] Table 2 Related properties of aluminum alloy products of Examples 1-4 and Comparative Examples 1-4 after long-term thermal stabilization

[0051]

[0052] The test results show that the 6182-T7 aluminum alloy prepared by the preparation method of the present invention can meet the following performance requirements: tensile strength ≥ 280MPa, yield strength: 230-280MPa, elongation ≥ 10%, bending angle ≥ 70°; after short-term stability at 190±5℃*45min, it meets the following requirements: tensile strength ≥ 280MPa, yield strength: 230-280MPa, elongation ≥ 10%, bending angle ≥ 70°; after long-term stability at 120±5℃*500h, it meets the following requirements: tensile strength ≥ 280MPa, yield strength: 230-280MPa, elongation ≥ 10%, bending angle ≥ 70°. Therefore, the 6182-T7 aluminum alloy prepared by the preparation method of the present invention can be used for the preparation of aluminum alloy universal joint brackets for vehicles, realizing localized production.

[0053] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A method for preparing 6182-T7 aluminum alloy, characterized in that: The following steps are involved: (1) Aluminum rod casting: Prepare the raw materials according to the alloying element composition of 6182 aluminum alloy and cast them into cast rods; (2) Homogenization treatment: the cast rod obtained in step (1) is kept at 510±5°C for 9-10 hours, and after homogenization treatment, it is taken out of the furnace and water-cooled to room temperature; (3) Preheating: heating the homogenized cast rod obtained in step (2) to 490-520°C, with a temperature gradient of 10-30°C between the head and tail of the cast rod; heating the extrusion die to 470-490°C; heating the die barrel to 430-440°C; (4) Extrusion: using an extruder to extrude the preheated cast rod in step (3) at a speed of 4-5 m / min; (5) Solution treatment: the product obtained in step (4) is subjected to online solution treatment, and an online water cooling method is adopted during the online solution treatment; (6) Straightening: straightening the product obtained in step (5); (7) forging the product obtained in step (6), and cooling it with water after forging; (8) Artificial aging treatment: The forging of the product obtained in step (7) is artificially aged in two stages: the first stage is aging at 175±5°C, and the holding time is 6-6.5 h; the second stage is aging at 205±5°C, and the holding time is 6-6.5 h, to obtain 6182-T7 aluminum alloy; The element composition of the 6182 aluminum alloy includes, by mass percentage: Si: 0.95%-1.1%, Fe≤0.25%, Cu≤0.1%, Mn: 0.8-0.9%, Mg: 0.9%-1.05%, Cr≤0.25%, Zn≤0.20%, Ti≤0.10%, Zr: 0.08-0.15%, other single elements≤0.05%, other impurity elements total≤0.15%, Al: balance; The 6182-T7 aluminum alloy meets the following performance requirements: tensile strength ≥ 280 MPa, yield strength: 230-280 MPa, elongation ≥ 10%, bending angle ≥ 70°; after short-term stability at 190±5°C*45min, the following requirements are met: tensile strength ≥ 280 MPa, yield strength: 230-280 MPa, elongation ≥ 10%, bending angle ≥ 70°; after long-term stability at 120±5°C*500h, the following requirements are met: tensile strength ≥ 280 MPa, yield strength: 230-280 MPa, elongation ≥ 10%, bending angle ≥ 70°.

2. A 6182-T7 aluminum alloy, characterized in that: The preparation method according to claim 1 is adopted.

3. An application of 6182-T7 aluminum alloy, characterized in that: The 6182-T7 aluminum alloy described in claim 2 is used to prepare aluminum alloy universal joint brackets for vehicles.

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