Short-process manufacturing method for 6-series aluminum alloy die forging

Abstract

The invention discloses a manufacturing method of a 6-series aluminum alloy die forging. The method comprises the following steps that a cast ingot is subjected to homogenization treatment for 12-16 h at the temperature of 540-560 DEG C, and then water spraying cooling is conducted; saw cutting is conducted according to the product size requirement; the sawn raw materials are heated at the temperature of 520-530 DEG C and then directly subjected to water quenching treatment; a manipulator is adopted for cold forging forming, and the applied pressure ranges from 2500 T to 4000 T; and finally, aging treatment is conducted for 8-10 h at the temperature of 175-185 DEG C. Wherein the working procedure interval time from heating quenching to cold forging and from cold forging to aging does not exceed 4 hours. The 6-series aluminum alloy die forging manufactured by the method comprises the following alloy components in percentage by mass: 1.21 to 1.39 percent of Si, 0.01 to 0.1 percent of Fe, 0.05 to 0.1 percent of Cu, 0.8 to 1.0 percent of Mn, 1.11 to 1.27 percent of Mg, 0.05 to 0.15 percent of Cr and the balance of Al. According to the method, the short-process technology is adopted, traditional multiple heating and forging procedures are simplified, mechanical arm automatic operation is combined, the production efficiency is remarkably improved, and the manufacturing cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of manufacturing 6 series aluminum alloy forgings, and in particular to a short-process manufacturing method for 6 series aluminum alloy die forgings. Background Art

[0002] With the rapid development of automated production and manufacturing technology, traditional aluminum alloy hot processing manufacturing processes are facing the need for optimization and upgrading. As the most widely used deformed aluminum alloy, 6 series aluminum alloy is widely used in construction, military and industrial fields. The manufacturing process of traditional 6 series aluminum alloy die forgings usually includes ingot casting → sawing → heating → initial forging → heating → final forging → heating → quenching → aging → packaging and other processes. This traditional multi-process manufacturing method has the disadvantages of repeated heating times, high energy consumption, and multiple forging processes occupying the main part of the processing cost. At the same time, the offline quenching process increases the difficulty of product quality control, the complex process leads to a long production cycle, and the low degree of automation leads to high labor costs, which can no longer meet the requirements of modern manufacturing.

[0003] In the prior art, CN103361520A discloses an aluminum alloy forging material for automobiles and a method for manufacturing the same. The method adopts a traditional manufacturing process, including casting at 700-780°C, followed by homogenization heat treatment at 480-560°C for 2-12 hours, then heating at 500-560°C, and hot forging at a temperature of 450-560°C, followed by multiple processes such as solution treatment, quenching and aging treatment. This method not only has many processes, but also requires forging at high temperatures, high energy consumption, and complex process parameter control. In addition, the method also requires a separate solution treatment process, which further increases the manufacturing cost.

[0004] Therefore, it is urgent to develop a new 6 series aluminum alloy die forging manufacturing process to achieve the goals of process streamlining, process optimization, and cost reduction, while ensuring the mechanical properties and yield rate of the products. Summary of the invention

[0005] In view of the shortcomings of the above-mentioned prior art, the present invention provides a short-process manufacturing method for 6-series aluminum alloy die forgings, which realizes rapid and low-cost manufacturing of 6-series aluminum alloy die forgings products by cross-combining forging technology, heat treatment technology and semi-automation technology.

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

[0007] A short-process manufacturing method for a 6-series aluminum alloy die forging, characterized in that it comprises the following steps:

[0008] 1) Ingot homogenization: The ingot is homogenized at 540-560°C for 12-16 hours, cooled to below 200°C by water spraying, and then air-cooled to room temperature;

[0009] 2) Sawing: sawing the homogenized ingot according to the specific size requirements of the die forging product, and the weight of the obtained raw material is 1-2.5kg;

[0010] 3) Heating and quenching: Place the sawn raw materials in a heating tunnel furnace and heat them to 520-530°C, so that the temperature at the furnace outlet is not less than 520°C, and then directly put the raw materials into the quenching water for quenching treatment, and the quenching water temperature is 30-60°C;

[0011] 4) Cold forging: The manipulator places the quenched raw material in the die forging machine, applies 2500-4000T pressure for cold forging, and the manipulator performs the unloading operation after forming;

[0012] 5) Artificial aging: The cold forged blank is aged at 175-185℃ for 8-10h;

[0013] The time interval between step 3) and step 4) does not exceed 4 hours, and the time interval between step 4) and step 5) does not exceed 4 hours.

[0014] According to the above manufacturing method, it is characterized in that the mass percentage of each component of the raw material is: Si:

[0015] 1.21-1.39%, Fe: 0.01-0.1%, Cu: 0.05-0.1%, Mn: 0.8-1.0%, Mg: 1.11-1.27%, Cr: 0.05-0.15%, and the rest is Al.

[0016] According to the above-mentioned manufacturing method, it is characterized in that the mass percentage of each component of the raw material is: Si: 1.3%, Fe: 0.05%, Cu: 0.08%, Mn: 0.9%, Mg: 1.19%, Cr: 0.1%, and the rest is Al.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. Significant technological innovation: The short process of "homogenization → sawing → heating and quenching → cold forging → aging" is adopted, which eliminates the multiple heating and repeated forging steps in the traditional process, and reduces the number of processes by more than 50%.

[0019] 2. Low manufacturing cost: Using room temperature cold forging instead of traditional hot forging significantly reduces energy consumption; combined with robotic automation operation, it reduces labor costs; simplified processes reduce manufacturing time.

[0020] 3. Excellent product performance: Through reasonable process parameter design and strict process interval time control, the mechanical properties of the product are ensured, achieving tensile strength ≥377MPa, yield strength ≥340MPa, and elongation ≥11%.

[0021] 4. High yield rate: By adopting appropriate homogenization technology and strict process control, the product yield rate reaches more than 93%, which is significantly higher than the traditional process.

[0022] 5. Good process stability: Through the automated operation of the robot and strict process interval time control, the stability and repeatability of the production process are guaranteed, which is conducive to the stable control of product quality. DETAILED DESCRIPTION

[0023] The present invention is described in detail below in conjunction with specific implementation modes.

[0024] Example 1

[0025] A 6 series aluminum alloy, the components and mass percentages of the aluminum alloy are: Si: 1.3%, Fe: 0.05%, Cu: 0.08%, Mn: 0.9%, Mg: 1.19%, Cr: 0.1%, and the rest is Al.

[0026] A short-process manufacturing method for a 6-series aluminum alloy die forging, comprising the following steps:

[0027] 1) Ingot homogenization: The ingot homogenization temperature is 550°C, the holding time is 14h, and the ingot is cooled by water spray. When it is cooled to below 200°C, it can be air-cooled to room temperature.

[0028] 2) Sawing: Sawing the ingot according to the specific length and size requirements of the die forging product, and prepare the raw materials, the weight of the raw materials is 2Kg.

[0029] 3) Heating and quenching: the raw materials sawn in step 2) are placed in a heating tunnel furnace according to the placement requirements for heating, the heating temperature is 530°C, and the temperature of the raw materials at the outlet of the tunnel furnace is not less than 520°C; after the raw materials are continuously run out of the tunnel furnace, they are directly put into the quenching water for quenching treatment, the quenching medium is water, and the water temperature is controlled at 45°C.

[0030] 4) Cold forging: The quenched raw material described in step 3) is placed in the die of the die forging machine. The placement process is completed by a robot according to the process design, and the pressure applied is in the range of 3500T until the die forging is formed. After the cold forging process is completed, the robot performs the unloading operation; the time interval between step 3) and step 4) shall not exceed 4h, and a cold forged blank is obtained in this step.

[0031] 5) Artificial aging: The cold forged blank in step 4) is artificially aged at 180°C for 9 hours. The interval between step 4) and step 5) shall not exceed 4 hours.

[0032] Example 2

[0033] A 6 series aluminum alloy, the components and mass percentages of the aluminum alloy are: Si: 1.21%, Fe: 0.1%, Cu: 0.1%, Mn: 0.8%, Mg: 1.27%, Cr: 0.05%, and the rest is Al.

[0034] A short-process manufacturing method for a 6-series aluminum alloy die forging, comprising the following steps:

[0035] 1) Ingot homogenization: The ingot homogenization temperature is 540°C, the holding time is 16h, and the ingot is cooled by water spray. When it is cooled to below 200°C, it can be air-cooled to room temperature.

[0036] 2) Sawing: Sawing the ingot according to the specific length and size requirements of the die forging product, and prepare the raw materials, the weight of the raw materials is 2.5Kg.

[0037] 3) Heating and quenching: the raw materials sawn in step 2) are placed in a heating tunnel furnace according to the placement requirements for heating, the heating temperature is 525°C, and the temperature of the raw materials at the outlet of the tunnel furnace is not less than 520°C; the raw materials are directly put into the quenching water after continuous operation from the tunnel furnace for quenching treatment, the quenching medium is water, and the water temperature is controlled between 60°C.

[0038] 4) Cold forging: The quenched raw material described in step 3) is placed in the die of the die forging machine. The placement process is completed by a robot according to the process design, and the pressure applied is in the range of 2500T until the die forging is formed. After the cold forging process is completed, the robot performs the unloading operation; the time interval between step 3) and step 4) shall not exceed 4h, and this step obtains a cold forged blank.

[0039] 5) Artificial aging: The cold forged blank in step 4) is artificially aged at 185°C for 8 hours. The interval between step 4) and step 5) shall not exceed 4 hours.

[0040] Example 3

[0041] A 6 series aluminum alloy, the components and mass percentages of the aluminum alloy are: Si: 1.39%, Fe: 0.01%, Cu: 0.05%, Mn: 1.0%, Mg: 1.11%, Cr: 0.15%, and the rest is Al.

[0042] A short-process manufacturing method for a 6-series aluminum alloy die forging, comprising the following steps:

[0043] 1) Ingot homogenization: The ingot homogenization temperature is 560°C, the holding time is 12h, and the ingot is cooled by water spray. When it is cooled to below 200°C, it can be air-cooled to room temperature.

[0044] 2) Sawing: Sawing the ingot according to the specific length and size requirements of the die forging product, and prepare the raw materials, the weight of the raw materials is 1 kg.

[0045] 3) Heating and quenching: the raw materials sawn in step 2) are placed in a heating tunnel furnace according to the placement requirements for heating, the heating temperature is 520°C, and the temperature of the raw materials at the outlet of the tunnel furnace is not less than 520°C; the raw materials are directly put into the quenching water after continuous operation from the tunnel furnace for quenching treatment, the quenching medium is water, and the water temperature is controlled between 30°C.

[0046] 4) Cold forging: The quenched raw material described in step 3) is placed in the die of the die forging machine. The placement process is completed by a robot according to the process design, and the pressure applied is in the range of 4000T until the die forging is formed. After the cold forging process is completed, the robot performs the unloading operation; the time interval between step 3) and step 4) shall not exceed 4h, and this step obtains a cold forged blank.

[0047] 5) Artificial aging: The cold forged blank in step 4) is artificially aged at 175°C for 10 hours. The interval between step 4) and step 5) shall not exceed 4 hours.

[0048] Example 4

[0049] The invention discloses a 6 series aluminum alloy, 6061 aluminum alloy, whose components and mass percentages are as follows: Si: 0.4-0.8%, Fe: 0.7%, Cu: 0.15-0.4%, Mn: 0.15%, Mg: 0.8-1.2%, Cr: 0.04-0.35%, Zn: 0.25%, Ti: 0.15, and the rest is Al.

[0050] A short-process manufacturing method for 6061 aluminum alloy die forgings, comprising the following steps:

[0051] 1) Ingot homogenization: The ingot homogenization temperature is 560°C, the holding time is 16h, and the ingot is cooled by water spray. When it is cooled to below 200°C, it can be air-cooled to room temperature.

[0052] 2) Sawing: Sawing the ingot according to the specific length and size requirements of the die forging product, and prepare the raw materials, the weight range of the raw materials is 1.8Kg.

[0053] 3) Heating and quenching: the raw materials sawn in step 2) are placed in a heating tunnel furnace according to the placement requirements for heating, the heating temperature is 520°C, and the temperature of the raw materials at the outlet of the tunnel furnace is not less than 520°C; the raw materials are directly put into the quenching water after continuous operation from the tunnel furnace for quenching treatment, the quenching medium is water, and the water temperature is controlled at 30°C.

[0054] 4) Cold forging: The quenched raw material described in step 3) is placed in the die of the die forging machine. The placement process is completed by a robot according to the process design, and the pressure applied is in the range of 2500T until the die forging is formed. After the cold forging process is completed, the robot performs the unloading operation; the time interval between step 3) and step 4) shall not exceed 4h, and this step obtains a cold forged blank.

[0055] 5) Artificial aging: The cold forged blank in step 4) is artificially aged at 185°C for 10 hours. The interval between step 4) and step 5) shall not exceed 4 hours.

[0056] Comparative Example 1

[0057] A 6 series aluminum alloy, the components and mass percentages of the aluminum alloy are: Si: 1.3, Fe: 0.05%, Cu: 0.08%, Mn: 0.9%, Mg: 1.19%, Cr: 0.1%, and the rest is Al.

[0058] A short-process manufacturing method for a 6-series aluminum alloy die forging, compared with Example 1, Comparative Example 1 adopts a traditional die forging process: ingot homogenization → sawing → heating → initial forging → trimming → heating → final forging → heating → quenching → aging → packaging. The rest is the same as Example 1.

[0059] Comparative Example 2

[0060] A 6 series aluminum alloy, the components and mass percentages of the aluminum alloy are: Si: 1.3, Fe: 0.05%, Cu: 0.08%, Mn: 0.9%, Mg: 1.19%, Cr: 0.1%, and the rest is Al.

[0061] A short-process manufacturing method for a 6-series aluminum alloy die forging, compared with Example 1, in the ingot homogenization process in Comparative Example 2: the ingot homogenization temperature is 550°C, the holding time is 2 hours, and the ingot is air-cooled to room temperature. The rest is the same as Example 1.

[0062] Comparative Example 3

[0063] A 6 series aluminum alloy, the components and mass percentages of the aluminum alloy are: Si: 1.3, Fe: 0.05%, Cu: 0.08%, Mn: 0.9%, Mg: 1.19%, Cr: 0.1%, and the rest is Al.

[0064] A short-process manufacturing method for a 6-series aluminum alloy die forging, compared with Example 1, the operation interval time between step 3) and step 4), and between step 4) and step 5) in comparative example 4 is not restricted. The rest is the same as Example 1.

[0065] The following table shows the mechanical properties of the 6 series aluminum alloy die forgings manufactured in Examples 1-2 of the present invention and Comparative Examples 1-3, respectively. The results are as follows:

[0066] Case Tensile strength MPa Yield strength MPa Elongation % Yield % Example 1 383 345 11 97 Example 2 377 340 11.5 93 Example 3 381 342 11.1 94 Example 4 306-316 270-280 ≥10 92-96 Comparative Example 1 372 339 10.9 94 Comparative Example 2 323 275 9.2 83 Comparative Example 3 244 206 9.7 90

[0067] The 6-series aluminum alloy die forgings obtained in Example 1-Example 2 have excellent mechanical properties, which shows that the forging process of the alloy is reasonable and the technical solution is feasible. Compared with Example 1, the 6-series aluminum alloy die forgings in Example 1 adopt the traditional die forging process. The results show that the mechanical properties of the die forgings in Example 1 are slightly different from those in Example 1, indicating that the material properties are not reduced while reducing the die forging process, indicating that the solution of the present invention is feasible. Compared with Example 1, the ingot homogenization process in Example 2 adopts the "high temperature + short time" homogenization process. The results show that the yield rate of the aluminum alloy die forgings in Example 2 is significantly reduced, indicating that the "high temperature + short time" homogenization process cannot make the unbalanced eutectic structure in the alloy ingot evenly distributed, the application in the casting is not fully released, the die forging size deviation is large, and the yield rate is low. Compared with Example 1, the time constraints between step 3) and step 4) and between step 4) and step 5) are cancelled in Comparative Example 3. The results show that the mechanical properties of the product in Comparative Example 3 are poor, indicating that the natural aging interval of the 6-series aluminum alloy after quenching is too long, and the subsequent artificial aging is not timely, resulting in a significant reduction in the mechanical properties of the aluminum alloy die forgings. In summary, the technical solution achieves short-process and low-cost manufacturing of 6-series aluminum alloy die forgings through ingot homogenization, sawing, heating quenching, cold forging, and artificial aging processes.

[0068] The above is only a preferred embodiment of the present invention and does not limit the invention. It should be pointed out that for ordinary technicians in this field, under the technical enlightenment provided by the present invention, other equivalent improvements can be made, all of which can achieve the purpose of the present invention and should be regarded as the protection scope of the present invention.

Claims

1. A short-process manufacturing method for 6 series aluminum alloy die forgings, characterized in that: The following steps are involved: 1) Ingot homogenization: The ingot is homogenized at 540-560°C for 12-16 hours, cooled to below 200°C by water spraying, and then air-cooled to room temperature; 2) Sawing: sawing the homogenized ingot according to the specific size requirements of the die forging product, and the weight of the obtained raw material is 1-2.5kg; 3) Heating and quenching: Place the sawn raw materials in a heating tunnel furnace and heat them to 520-530°C, so that the temperature at the furnace outlet is not less than 520°C, and then directly put the raw materials into the quenching water for quenching treatment, and the quenching water temperature is 30-60°C; 4) Cold forging: The manipulator places the quenched raw material in the die forging machine, applies 2500-4000T pressure for cold forging, and the manipulator performs the unloading operation after forming; 5) Artificial aging: The cold forged blank is aged at 175-185℃ for 8-10h; The time interval between step 3) and step 4) does not exceed 4 hours, and the time interval between step 4) and step 5) does not exceed 4 hours.

2. The manufacturing method according to claim 1, characterized in that: The mass percentage of each component of the raw material is as follows: Si: 1.21-1.39%, Fe: 0.01-0.1%, Cu: 0.05-0.1%, Mn: 0.8-1.0%, Mg: 1.11-1.27%, Cr: 0.05-0.15%, and the rest is Al.

3. The manufacturing method according to claim 2, characterized in that: The mass percentage of each component of the raw material is: Si: 1.3%, Fe: 0.05%, Cu: 0.08%, Mn: 0.9%, Mg: 1.19%, Cr: 0.1%, and the rest is Al.