Method for manufacturing an aluminum alloy stay for an open wagon

Abstract

The application provides a manufacturing method of an aluminum alloy support rod for an open wagon, comprising the following steps: casting an aluminum alloy round ingot; bending after first heat treatment of the aluminum alloy round ingot; second heat treatment of the aluminum alloy round ingot; milling groove treatment on both ends of the aluminum alloy pipe and the aluminum alloy round ingot, and punching after assembling the aluminum alloy pipe to both ends of the aluminum alloy round ingot to obtain the aluminum alloy support rod. The manufacturing method of the aluminum alloy support rod can significantly improve the strength of the aluminum alloy round ingot by sequentially performing the first heat treatment, the bending and the second heat treatment on the aluminum alloy round ingot, can further improve the strength of both ends of the aluminum alloy support rod by additionally arranging the aluminum alloy pipe on both ends of the bent aluminum alloy round ingot, so as to meet the requirements of the aluminum alloy open wagon, reduce the maintenance cost and the maintenance frequency of the aluminum alloy open wagon, and improve the transportation efficiency.

Description

Technical Field

[0001] This invention relates to the field of machining technology, and in particular to a method for manufacturing an aluminum alloy strut for open wagons. Background Technology

[0002] The C80 open wagon is an 80-ton capacity aluminum alloy coal wagon. Each aluminum alloy wagon is 700 kg lighter than a stainless steel wagon, resulting in better economic efficiency. The wagon's roof has three concave struts to support the wagon and prevent expansion. Inside the wagon, apart from these three struts which are made of steel, all other components are made of aluminum alloy. Steel struts have a lifespan of only 5-6 years, while aluminum alloy coal wagons are designed for a lifespan of over 25 years. This mismatch between the steel struts and the overall lifespan of the wagon leads to frequent maintenance and replacement of the steel struts, increasing maintenance costs and reducing transportation efficiency. Replacing the struts with more corrosion-resistant aluminum alloy would extend their lifespan to over 25 years, making the lifespan of all components more consistent and improving compatibility, thus reducing maintenance and replacement frequency. Furthermore, aluminum alloy has excellent recyclability, and scrap aluminum alloy retains more value.

[0003] However, aluminum alloy struts of the same size are weaker than steel struts, so the strength of aluminum alloy struts needs to be increased to meet the requirements of aluminum alloy open wagons. Summary of the Invention

[0004] This invention provides a method for manufacturing aluminum alloy struts for open wagons, thereby reducing the maintenance cost and frequency of maintenance for aluminum alloy open wagons and improving transportation efficiency.

[0005] This invention provides a method for manufacturing an aluminum alloy strut for a wagon, comprising the following steps:

[0006] S1. Cast aluminum alloy round ingot;

[0007] S2. The aluminum alloy round ingot is bent after undergoing a first heat treatment;

[0008] S3. Perform a second heat treatment on the aluminum alloy round ingot;

[0009] S4. Mill grooves at both ends of the aluminum alloy tube and the aluminum alloy round ingot. After assembling the aluminum alloy tube to both ends of the aluminum alloy round ingot, drill holes to obtain the aluminum alloy support rod.

[0010] In one embodiment, in step S1, the aluminum alloy round ingot is cast using a vertical shaft at a casting temperature of 680-720°C, a casting speed of 32-46 mm / min, a water pressure of 0.08 MPa, and a water flow rate of 15-20 L / min.

[0011] In one embodiment, the first heat treatment includes heating and quenching, with the heating temperature being 515-570℃, the holding time being 5-12h, and the quenching medium temperature being 1-30℃.

[0012] In one embodiment, the time interval between the end of heat preservation and quenching in the quenching medium for the aluminum alloy round ingot is less than 5 minutes.

[0013] In one embodiment, the heating temperature of the second heat treatment is 170-190°C, and the holding time is 8-12 hours.

[0014] In one embodiment, the time interval between the first heat treatment and the second heat treatment is less than 15 days.

[0015] In one embodiment, the aluminum alloy round ingot is 6061 aluminum alloy.

[0016] In one embodiment, the method for manufacturing the aluminum alloy strut further includes the following steps:

[0017] S5. Perform dimensional inspection on the aluminum alloy struts;

[0018] S6. Perform welding, polishing and painting on the aluminum alloy struts.

[0019] In one embodiment, the aluminum alloy round ingot has a diameter of 80 mm, and the inner and outer diameters of the aluminum alloy tube are 80 mm and 120 mm, respectively. Both the aluminum alloy round ingot and the aluminum alloy tube are made of 6061 aluminum alloy.

[0020] In one embodiment, the aluminum alloy round ingot and the aluminum alloy tube are welded using 4043 or 5356 aluminum alloy welding wire.

[0021] The present invention provides a method for manufacturing an aluminum alloy strut for open wagons, which, compared with the prior art, has at least the following advantages:

[0022] The manufacturing method of the aluminum alloy strut of the present invention significantly improves the strength of the aluminum alloy round ingot by sequentially performing a first heat treatment, bending, and a second heat treatment on the aluminum alloy round ingot. By adding aluminum alloy tubes to both ends of the bent aluminum alloy round ingot, the strength of both ends of the aluminum alloy strut can be further improved, thereby meeting the requirements of aluminum alloy open wagons, reducing the maintenance cost and frequency of maintenance of aluminum alloy open wagons, and improving transportation efficiency. Attached Figure Description

[0023] The invention will be described in more detail below based on embodiments and with reference to the accompanying drawings.

[0024] Figure 1This is a flowchart of the manufacturing method of aluminum alloy struts for open wagons in an embodiment of the present invention. Detailed Implementation

[0025] The present invention will be further described below.

[0026] like Figure 1 As shown, the manufacturing method of the aluminum alloy strut for open wagons of the present invention includes the following steps:

[0027] S1. Cast aluminum alloy round ingot;

[0028] S2. Bending the aluminum alloy round ingot after the first heat treatment;

[0029] S3. Perform a second heat treatment on the aluminum alloy round ingot;

[0030] S4. Mill grooves at both ends of the aluminum alloy tube and the aluminum alloy round ingot. After assembling the aluminum alloy tube to both ends of the aluminum alloy round ingot, drill holes to obtain the aluminum alloy strut.

[0031] Aluminum alloys generally consist of α-Al solid solution and a second phase. After solution treatment, most solute elements such as silicon, magnesium, iron, and copper are essentially incorporated into the α-Al solid solution, significantly reducing the amount of the second phase. The matrix structure is essentially transformed into a supersaturated α-Al solid solution. The solid solution contains a high proportion of solvent metal (i.e., aluminum) and a low content of solute elements, resulting in properties close to pure aluminum. Simultaneously, the solution treatment dissolves a large amount of the second phase, reducing its strengthening effect on the matrix and improving plasticity. After solution treatment, aluminum alloy round ingots exhibit higher plasticity. Therefore, for the same bending radius, the ultimate bending angle of the solution-treated aluminum alloy round ingot is larger. Through the aforementioned solution treatment, the microstructure of aluminum alloy round ingots is significantly improved, plasticity is greatly enhanced, and bending performance is improved, making it less prone to cracking when bending.

[0032] The manufacturing method of the aluminum alloy strut of the present invention significantly improves the strength of the aluminum alloy round ingot by sequentially performing a first heat treatment, bending, and a second heat treatment on the aluminum alloy round ingot. By adding aluminum alloy tubes to both ends of the bent aluminum alloy round ingot, the strength of both ends of the aluminum alloy strut can be further improved, thereby meeting the requirements of aluminum alloy open wagons, reducing the maintenance cost and frequency of maintenance of aluminum alloy open wagons, and improving transportation efficiency.

[0033] Specifically, in step S1, aluminum alloy round ingots are cast using a vertical shaft at a casting temperature of 680-720℃, a casting speed of 32-46 mm / min, a water pressure of 0.08 MPa, and a water flow rate of 15-20 L / min.

[0034] In step S2, the first heat treatment includes heating and quenching. The heating temperature is 515-570℃, the holding time is 5-12h, and the quenching medium temperature is 1-30℃.

[0035] Furthermore, the time interval between the end of heat preservation and quenching in the quenching medium for aluminum alloy round ingots is less than 5 minutes.

[0036] In step S3, the heating temperature for the second heat treatment is 170-190℃, and the holding time is 8-12h.

[0037] Furthermore, the time interval between the first heat treatment and the second heat treatment is less than 15 days.

[0038] The material for aluminum alloy round ingots can be 6061 aluminum alloy, which has good formability, weldability and machinability.

[0039] Steps S4 are followed by steps S5 and S6:

[0040] S5. Perform dimensional inspection on the aluminum alloy struts;

[0041] S6. Perform welding, polishing and painting on the aluminum alloy struts.

[0042] Step S5 involves dimensional inspection of the aluminum alloy struts before loading to ensure that all dimensions meet the loading requirements. Step S6 involves repairing and polishing dents on the strut surface caused by impacts, and simultaneously applying chrome silver powder paint to enhance the appearance of the aluminum alloy struts.

[0043] Specifically, the aluminum alloy round ingot has a diameter of 80mm, and the inner and outer diameters of the aluminum alloy tube are 80mm and 120mm respectively. The aluminum alloy tube is sleeved on both ends of the aluminum alloy round ingot to strengthen the strength of both ends of the aluminum alloy strut.

[0044] Furthermore, aluminum alloy round ingots and aluminum alloy tubes are welded using 4043 or 5356 aluminum alloy welding wire.

[0045] Example 1

[0046] 6061 aluminum alloy round ingots were cast using a vertical shaft. The elemental composition of the 6061 aluminum alloy round ingots was as follows: silicon 0.69%, iron 0.09%, copper 0.31%, manganese 0.01%, magnesium 1.1%, chromium 0.2%, zinc 0.01%, and titanium 0.11%. The casting temperature was 692℃, the casting speed was 41 mm / min, the water pressure was 0.08 MPa, and the water flow rate was 17 L / min. An online degassing device was used to degas the aluminum melt online. The diameter of the 6061 aluminum alloy round ingots was 80 mm.

[0047] Solution treatment was performed on 6061 aluminum alloy round ingots. The heating temperature was 560℃, the holding time was 8h, the quenching medium was water, the quenching medium temperature was 25℃, and the time interval from the end of the holding time to the quenching in the quenching medium was 3min.

[0048] At room temperature, aluminum alloy round ingots are placed on a bending machine for bending. The bending radius of the aluminum alloy round ingots during bending is 300mm, and the bending angle is 32.5°. After bending and inspection, the aluminum alloy round ingots that have no problems are subjected to aging treatment. The bent aluminum alloy round ingots are placed in a heat treatment furnace, with an interval of 8 days between the first heat treatment and the second heat treatment. The aging temperature is 180℃, the aging time is 12 hours, and the cooling method is air cooling after removal from the furnace.

[0049] The 6061 aluminum alloy tube and the aged aluminum alloy round ingot were milled with grooves. Using the centerline of the aluminum alloy strut as a reference, the parallelism of the groove centerlines at both ends was 0.3mm. After spot welding the connection between the aluminum alloy round ingot and the 6061 aluminum alloy tube, 5356 aluminum alloy welding wire was used for welding, with a weld height of 25mm. Then, the aluminum alloy strut was chamfered and drilled, with the center distance between the holes at both ends of the aluminum alloy strut being 2782mm.

[0050] The machined aluminum alloy struts are installed on a dimensional inspection platform for dimensional verification. Finally, the pits on the surface of the aluminum alloy struts are repaired by welding, and then chrome-plated silver paint is sprayed onto the surface to obtain the finished aluminum alloy struts.

[0051] After testing, the aluminum alloy strut has a tensile strength of 370MPa and a yield strength of 350MPa, and there were no cracks or breaks at its bends, indicating excellent final performance.

[0052] Example 2

[0053] 6061 aluminum alloy round ingots were cast using a vertical shaft. The elemental composition of the 6061 aluminum alloy round ingots was as follows: silicon 0.7%, iron 0.11%, copper 0.3%, manganese 0.01%, magnesium 1.1%, chromium 0.2%, zinc 0.01%, and titanium 0.12%. The casting temperature was 700℃, the casting speed was 42 mm / min, the water pressure was 0.08 MPa, and the water flow rate was 18 L / min. An online degassing device was used to degas the aluminum melt online. The diameter of the 6061 aluminum alloy round ingots was 80 mm.

[0054] Solution treatment was performed on 6061 aluminum alloy round ingots. The heating temperature was 570℃, the holding time was 9h, the quenching medium was water, the quenching medium temperature was 27℃, and the time interval from the end of the holding time to the quenching in the quenching medium was 4min.

[0055] At room temperature, aluminum alloy round ingots are placed on a bending machine for bending. The bending radius of the aluminum alloy round ingots during bending is 300mm, and the bending angle is 32.5°. After bending and inspection, the aluminum alloy round ingots that have no problems are subjected to aging treatment. The bent aluminum alloy round ingots are placed in a heat treatment furnace, with an interval of 9 days between the first heat treatment and the second heat treatment. The aging temperature is 185℃, the aging time is 11 hours, and the cooling method is air cooling after removal from the furnace.

[0056] The 6061 aluminum alloy tube and the aged aluminum alloy round ingot were milled with grooves. Using the centerline of the aluminum alloy strut as a reference, the parallelism of the groove centerlines at both ends was 0.3mm. After spot welding the connection between the aluminum alloy round ingot and the 6061 aluminum alloy tube, 4043 aluminum alloy welding wire was used for welding, with a weld height of 25mm. Then, the aluminum alloy strut was chamfered and drilled, with the center distance between the holes at both ends of the strut being 2782mm.

[0057] The machined aluminum alloy struts are installed on a dimensional inspection platform for dimensional verification. Finally, the pits on the surface of the aluminum alloy struts are repaired by welding, and then chrome-plated silver paint is sprayed onto the surface to obtain the finished aluminum alloy struts.

[0058] After testing, the aluminum alloy strut has a tensile strength of 360MPa and a yield strength of 325MPa, and there were no cracks or breaks at its bends, resulting in excellent performance.

[0059] Comparative Example 1

[0060] First, heat the 6061 aluminum alloy round ingot to 500℃ and hold it for 3 hours. After holding for 3 hours, remove the aluminum alloy round ingot and quickly quench it at 450℃ using water as the medium at 25℃. After the aluminum alloy round ingot cools to 40℃, remove it and bend it at room temperature using a bending machine. Then, test the bending effect, tensile strength, and yield strength.

[0061] Test results: The aluminum alloy round ingot fractured at the bend, with a tensile strength of 280 MPa and a yield strength of 260 MPa.

[0062] Comparative Example 2

[0063] First, heat the 6063 aluminum alloy round ingot to 490℃ and hold it for 4 hours. After holding for 4 hours, remove the aluminum alloy round ingot and quickly quench it with water at a temperature of 25℃. After the aluminum alloy round ingot cools to 40℃, remove it and bend it at room temperature using a bending machine. Then, test the bending effect, tensile strength, and yield strength.

[0064] Test results: The aluminum alloy round ingot fractured at the bend, with a tensile strength of 270 MPa and a yield strength of 250 MPa.

[0065] Comparative Example 3

[0066] First, heat the ZL205A aluminum alloy round ingot to 500℃ and hold it for 4 hours. After holding for 4 hours, remove the aluminum alloy round ingot and quickly quench it with oil at a temperature of 25℃. After the aluminum alloy round ingot cools to 40℃, remove it and bend it at room temperature using a bending machine. Then, test the bending effect, tensile strength, and yield strength.

[0067] Test results: The aluminum alloy round ingot fractured at the bend, with a tensile strength of 260 MPa and a yield strength of 255 MPa.

[0068] Comparing the above embodiments with Comparative Examples 1-3, it can be seen that the manufacturing method of the aluminum alloy strut of the present invention effectively improves the bending performance, tensile strength and yield strength of the aluminum alloy round ingot, and can meet the manufacturing requirements of aluminum alloy struts.

[0069] Although the invention has been described with reference to preferred embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, the technical features mentioned in the various embodiments can be combined in any manner as long as there is no structural conflict. The invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method for manufacturing an aluminum alloy strut for a wagon, characterized in that, Includes the following steps: S1. Cast aluminum alloy round ingot; S2. The aluminum alloy round ingot is bent after undergoing a first heat treatment; S3. Perform a second heat treatment on the aluminum alloy round ingot; S4. Mill grooves at both ends of the aluminum alloy tube and the aluminum alloy round ingot, assemble the aluminum alloy tube to both ends of the aluminum alloy round ingot, and then drill holes to obtain the aluminum alloy support rod. In step S1, the aluminum alloy round ingot is cast using a vertical shaft at a casting temperature of 680-720℃, a casting speed of 32-46mm / min, a water pressure of 0.08MPa, and a water flow rate of 15-20L / min. The first heat treatment includes heating and quenching. The heating temperature is 515-570℃, the holding time is 5-12h, and the quenching medium temperature is 1-30℃. The time interval between the end of the holding and the quenching in the aluminum alloy round ingot is less than 5min. The heating temperature of the second heat treatment is 170-190℃, and the holding time is 8-12h. The time interval between the first heat treatment and the second heat treatment is less than 15 days. The aluminum alloy round ingot is made of 6061 aluminum alloy and has a diameter of 80mm. The inner diameter and outer diameter of the aluminum alloy tube are 80mm and 120mm, respectively. Both the aluminum alloy round ingot and the aluminum alloy tube are made of 6061 aluminum alloy.

2. The method for manufacturing aluminum alloy struts for open wagons according to claim 1, characterized in that, It also includes the following steps: S5. Perform dimensional inspection on the aluminum alloy struts; S6. Perform welding, polishing and painting on the aluminum alloy struts.

3. The method for manufacturing aluminum alloy struts for open wagons according to claim 1, characterized in that, The aluminum alloy round ingot and the aluminum alloy tube are welded using 4043 or 5356 aluminum alloy welding wire.

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