A heat treatment method for copper alloy sheet parts

Abstract

This invention discloses a heat treatment method for copper alloy sheet parts. The method involves cleaning and drying the copper alloy sheet parts, heat treatment chamber, and rack. The parts are then vertically suspended and spaced apart within the rack's compartments. The parts and rack are placed inside the heat treatment chamber, the lid is closed, and filler material is placed in the annular groove around the lid. Charcoal is also placed inside the heat treatment chamber. After solution treatment, the rack containing the parts is removed and immersed in water for cooling and drying. The parts are then vertically suspended and spaced apart within the rack's compartments again. The parts and rack are placed back into the heat treatment chamber, the lid is closed, and filler material is placed in the annular groove around the lid. After aging treatment, the rack containing the parts is removed and cooled in air. After cooling, the rack is lifted out, and the parts are unloaded. This invention solves the problems of low production efficiency and narrow applicability associated with atmosphere-protected heat treatment, and the problems of complex control and low production efficiency associated with vacuum heat treatment in existing copper alloy processing methods.

Description

Technical Field

[0001] This invention relates to, but is not limited to, the field of non-ferrous metal heat treatment technology, specifically to the field of processing technology for copper alloy sheet parts used in aircraft DC generators, and particularly to a heat treatment method for copper alloy sheet parts. Background Technology

[0002] Copper alloys are classified into brass, bronze, and cupronickel, and have two strengthening mechanisms: non-heat-treatable strengthening and heat-treatable strengthening. Among them, heat-treatable copper alloys are a commonly used material for rotor end plate parts used in aircraft DC generators. Their performance requirements demand maximum strength, which necessitates heat treatment to ensure optimal performance.

[0003] Currently, the conventional methods for preventing copper alloy oxidation through solution treatment and aging heat treatment are atmosphere-protected heat treatment and vacuum heat treatment. Atmosphere-protected heat treatment has strict requirements on the type and concentration of the atmosphere; different copper alloys require different atmospheres. This necessitates strict control of process parameters (including the type, flow rate, and concentration of the introduced gas) during atmosphere protection, resulting in low production efficiency and unsuitability for different types of copper alloys. Furthermore, while vacuum heat treatment effectively prevents oxidation of copper alloys at high temperatures, certain metallic elements in copper alloys tend to volatilize when heated in a high vacuum, leading to changes in the alloy's strength, ductility, and other properties. This necessitates that vacuum heat treatment of copper alloys be performed using low vacuum or inert gas refill protection. This method is complex to control, has low production efficiency, and requires high-capacity equipment. Summary of the Invention

[0004] The purpose of this invention is to solve the above-mentioned technical problems. This invention provides a heat treatment method for copper alloy sheet parts, which solves the problems of low production efficiency and narrow applicability of atmospheric heat treatment and the problems of complex control and low production efficiency of vacuum heat treatment in existing copper alloy processing methods.

[0005] The technical solution of the present invention: The embodiments of the present invention provide a heat treatment method for copper alloy plate parts, including:

[0006] Step 1: Clean the copper alloy sheet parts, heat treatment chamber, and rack, and dry them with compressed air;

[0007] Step 2: Hang at least one copper alloy sheet part vertically in the shelf compartment, with a minimum spacing of 10mm between adjacent parts;

[0008] Step 3: Place the rack containing the parts into the heat treatment chamber, close the lid, and place filler in the annular groove around the lid until the filler is roughly level with the upper edge of the annular groove; charcoal is also placed in the heat treatment chamber.

[0009] Step 4, solution treatment, includes: placing the heat treatment box containing the parts and rack into an air furnace for solution treatment. The heating temperature and holding time in the solution treatment are determined according to the material of the parts.

[0010] Step 5: Open the box cover, take out the rack containing the parts and put it into water to cool. After cooling, lift out the rack and remove the parts. Use compressed air to dry the parts.

[0011] Step 6: After solution treatment and drying, the copper alloy sheet parts are vertically suspended in the partition of the rack, with a minimum spacing of 10mm between adjacent parts.

[0012] Step 7: Place the rack containing the parts into the heat treatment chamber, close the lid, and place filler in the annular groove around the lid until the height of the filler is basically flush with the upper edge of the annular groove.

[0013] Step 8, aging treatment, includes: placing the heat treatment box containing the parts and racks into an air furnace for aging treatment. The heating temperature and holding time during the aging treatment are determined according to the material of the parts.

[0014] Step 9: Open the box cover, take out the rack containing the parts and cool it in the air. After cooling, lift the rack out and unload the parts.

[0015] Optionally, in the heat treatment method for copper alloy sheet parts as described above,

[0016] The material rack 4 is configured as a column frame structure. The material rack 4 includes a rack bottom and a rack top arranged in parallel, and a support column connecting the rack bottom and the rack top. Multiple partitions are arranged in parallel on the rack top for vertically placing copper alloy plate parts into the material rack and separating them by the partitions.

[0017] The dimensions of the material rack 4 are set such that after the bottom of the material rack 4 is placed into the heat treatment box, all other structures of the material rack 4 except the bottom are at least 50mm away from the inner wall of the heat treatment box.

[0018] Optionally, in the heat treatment method for copper alloy sheet parts as described above, the heat treatment box includes: a cylindrical box body 1 with one end open and a box cover 2. An outer cylindrical wall 3 extends from the outer side of the open end of the cylindrical box body 1 along the periphery of the cylindrical wall, and the bottom end face of the outer cylindrical wall 3 communicates with the upper part of the cylindrical wall to form an annular box groove 3a between the open end of the cylindrical wall and the outer cylindrical wall.

[0019] Optionally, in the heat treatment method for copper alloy sheet parts as described above,

[0020] In step 4, the heat treatment box containing charcoal, parts and material racks is placed in an air furnace to solidify the parts. The charcoal is used to react with a small amount of oxygen in the box at high temperature to prevent the oxygen from reacting with the surface of the parts to form an oxide layer.

[0021] Optionally, in the heat treatment method for copper alloy sheet parts as described above,

[0022] The cooling method in step 5 is to use a hook to lift the rack containing the parts, transfer it horizontally to the top of the water tank, and place it vertically into the water for a preset time.

[0023] Optionally, in the heat treatment method for copper alloy sheet parts as described above,

[0024] In steps 2 and 6, the copper alloy sheet parts are tied together with unplated iron wire and then vertically suspended in the partition of the material rack.

[0025] Optionally, in the heat treatment method for copper alloy sheet parts as described above,

[0026] In step 9, the rack containing the parts is lifted with a hook and placed on the ground in a safe area to cool in room temperature air.

[0027] Optionally, in the heat treatment method for copper alloy sheet parts as described above,

[0028] In steps 3 and 7, fine sand is filled into the annular groove around the box cover as a filler. The fine sand is artificial sand with a particle diameter of less than 0.25 mm. The fine sand is used to isolate the parts from the circulation of air inside the furnace, ensuring that the surface of the parts does not oxidize when heated.

[0029] The beneficial effects of this invention: This invention provides a heat treatment method for copper alloy sheet parts, including solution treatment and aging treatment. It utilizes a self-developed and manufactured rack and heat treatment chamber. The method involves cleaning the copper alloy sheet parts, heat treatment chamber, and rack; binding the parts; vertically suspending them on the rack; placing the rack inside the heat treatment chamber; covering the chamber; sealing the chamber with clean filler (e.g., fine sand); and placing the heat treatment chamber in a box-type resistance air furnace for solution treatment and aging treatment. After solution treatment and aging treatment, water cooling is performed, followed by air cooling. This heat treatment method can be used for the heat treatment of copper alloy sheet parts, resulting in parts that are oxidation-free, have high strength, and minimal deformation after heat treatment, meeting product size and performance requirements. Furthermore, the method is simple to operate, and the heat treatment chamber and rack used are simple in structure, reusable, and low in cost. Verification has shown that the heat-treated copper alloy sheet parts are oxidation-free, have high strength, and minimal deformation, meeting the size and performance requirements of the copper alloy sheet parts. Furthermore, in the heat treatment method provided by this invention, the charcoal placed in the heat treatment chamber before the solution treatment can react with a small amount of oxygen in the chamber at high temperature, preventing the oxygen from reacting with the surface of the parts to form an oxide layer. Moreover, in the process of implementing the solution treatment method, by placing the heat treatment chamber in an air furnace, the heat treatment chamber is in the atmospheric environment of the air furnace, and the entire process does not require the introduction of gas or the control of gas parameters. Furthermore, in the process of implementing the aging treatment method, by placing the heat treatment chamber in an air furnace, the heat treatment chamber is in the atmospheric environment of the air furnace, and the entire process does not require the introduction of gas or the control of gas parameters. Attached Figure Description

[0030] The accompanying drawings are provided to further understand the technical solutions of the present invention and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of the present invention and do not constitute a limitation on the technical solutions of the present invention.

[0031] Figure 1 This is a schematic diagram of the material rack structure used in the heat treatment method for copper alloy sheet parts provided in an embodiment of the present invention. Figure 1 Figures a and b in the diagram are schematic diagrams from different angles, figure c is a top view, and figure d is a three-dimensional structural schematic diagram.

[0032] Figure 2 A schematic diagram of the copper alloy sheet parts to be processed by the heat treatment method for copper alloy sheet parts provided in the embodiments of the present invention;

[0033] Figures 3a to 3c This is a schematic diagram of the heat treatment chamber used in the heat treatment method for copper alloy sheet parts provided in an embodiment of the present invention. Figure 3a and Figure 3b These are cross-sectional views at different angles. Figure 3c The image is a top view. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

[0035] The background section has already explained the existing processing methods for copper alloy parts and their inherent problems. To address these issues, this invention provides a heat treatment method for copper alloy sheet parts, improving upon the current situation where atmosphere-protected heat treatment for copper alloys suffers from low production efficiency and narrow applicability, and vacuum heat treatment is complex to control and also inefficient. The heat treatment method for copper alloy sheet parts provided by this invention can be used for the heat treatment of copper alloy sheet parts, resulting in parts that are oxidation-free, have high strength, and minimal deformation after heat treatment, thus meeting product size and performance requirements.

[0036] The present invention provides the following specific embodiments, which can be combined with each other. For the same or similar concepts or processes, they may not be described again in some embodiments.

[0037] To address the issues of low production efficiency and limited applicability associated with atmosphere-protected heat treatment of copper alloys, and the problems of complex control and low production efficiency associated with vacuum heat treatment, this invention provides a heat treatment method for copper alloy sheet parts, based on current equipment conditions. The heat treatment method provided by this invention employs solution treatment and aging treatment, and includes the following steps:

[0038] Step 1: Clean the copper alloy sheet parts, heat treatment chamber, and rack, and dry them with compressed air;

[0039] In this step, the copper alloy sheet parts, heat treatment box and material rack are cleaned with cleaning agent and dried with compressed air to ensure that the surface is free of oil and other residues after cleaning.

[0040] Step 2: Hang at least one copper alloy sheet part vertically in the shelf compartment, with a minimum spacing of 10mm between adjacent parts;

[0041] In this step, copper alloy sheet parts can be bound together with Φ0.8 double-strand iron wire without plating and hung vertically on the material rack, with the parts spaced ≥10mm apart.

[0042] Step 3: Place the rack containing the parts into the heat treatment chamber, close the lid, and place filler in the annular groove around the lid until the filler is roughly level with the upper edge of the annular groove; charcoal is also placed in the heat treatment chamber.

[0043] In this step, it should be noted that the filler material is, for example, fine sand; in addition, the charcoal placed in the heat treatment chamber is used to react with the small amount of oxygen in the chamber at high temperature to prevent the oxygen from reacting with the surface of the parts and forming an oxide layer on the surface of the parts.

[0044] Step 4, solution treatment, includes: placing the heat treatment box containing the parts and rack into an air furnace for solution treatment. The heating temperature and holding time in the solution treatment are determined according to the material of the parts.

[0045] The solution treatment method of the present invention is as follows: by placing the heat treatment box in an air furnace, the heat treatment box is in the atmospheric environment of the air furnace, and the whole process does not require the introduction of gas or the control of gas parameters.

[0046] Step 5: Use an iron hook to open the box cover, use the iron hook to remove and lift the rack containing the parts, and put it into water to cool. After cooling, lift the rack out and remove the parts, then use compressed air to dry the parts.

[0047] During this step, when placing the item in the water, be careful to move it horizontally above the water tank and then vertically into the water for 1 minute.

[0048] It should be noted that, since copper alloy sheet parts consist of a copper matrix and alloying elements, during the solution heating process, the alloying elements in the copper alloy sheet parts dissolve in the copper matrix, and cooling prevents the alloying elements from precipitating out of the copper matrix, thus forming a uniform solid solution.

[0049] Step 6: After solution treatment and drying, the copper alloy sheet parts are vertically suspended in the partition of the rack, with a minimum spacing of 10mm between adjacent parts.

[0050] It should be noted that the reason for using uncoated iron wire in steps 2 and 6 of the present invention is that the iron wire is placed in the air furnace together with the material rack and the heat treatment box. If coated iron wire is used, the coating is generally zinc-plated, which will volatilize at high temperature and thus contaminate the parts.

[0051] Step 7: Place the rack containing the parts into the heat treatment chamber, close the chamber lid, and place filler in the annular groove around the lid until the filler height is basically flush with the upper edge of the annular groove; the filler in this step is, for example, fine sand.

[0052] Step 8, aging treatment, includes: placing the heat treatment box containing the parts and racks into an air furnace for aging treatment. The heating temperature and holding time during the aging treatment are determined according to the material of the parts.

[0053] In this embodiment of the invention, the aging process is as follows: the heat treatment chamber is placed in an air furnace, and the heat treatment chamber is in the atmospheric environment of the air furnace. The entire process does not require the introduction of gas or the control of gas parameters.

[0054] Step 9: Use an iron hook to open the box cover, use the iron hook to remove and lift the rack containing the parts to cool it in the air, lift the rack out after cooling, and unload the parts after cooling.

[0055] In this step, it is important to place the rack containing the parts on the ground in a safe area and allow it to cool in room temperature air. Additionally, the aforementioned solution treatment of the parts can dissolve all or most of the alloying elements into the copper matrix. After cooling to room temperature, a part with a solid solution is obtained. By aging the part with the solid solution at room temperature or a higher temperature, the solid solution decomposes and precipitates a second phase. This precipitated second phase can significantly increase the strength and hardness of the part.

[0056] In one implementation of this invention, such as Figure 1 The diagram shown is a schematic representation of the material rack used in the heat treatment method for copper alloy sheet parts provided in an embodiment of the present invention. Figure 1 Figures a and b in the diagram are schematic diagrams from different angles, figure c is a top view, and figure d is a three-dimensional structural schematic diagram. In this implementation, the material rack 4 is set as a columnar frame structure. The material rack 4 includes a parallel base and a top, and a support column connecting the base and top. Multiple partitions are arranged parallel to each other on the top for vertically placing copper alloy sheet parts into the rack and separating them through the partitions. For example... Figure 2 The diagram shown is a schematic of the copper alloy sheet parts to be processed by the heat treatment method for copper alloy sheet parts provided in the embodiment of the present invention.

[0057] In this implementation, the principle for setting the size of the rack 4 is as follows: after the bottom of the rack 4 is placed into the heat treatment box, all other structures of the rack 4 except the bottom are at least 50mm away from the inner wall of the heat treatment box.

[0058] In one implementation of this invention, such as Figures 3a to 3c The diagram shown is a structural schematic of the heat treatment chamber used in the heat treatment method for copper alloy sheet parts provided in an embodiment of the present invention. Figure 3a and Figure 3b These are cross-sectional views at different angles. Figure 3cThe figure shows a top view. The heat treatment box in this implementation includes: a cylindrical box body 1 with one end open and a box cover 2. An outer cylindrical wall 3 extends from the outer side of the open end of the cylindrical box body 1 along the perimeter of the cylindrical wall, and the bottom end face of the outer cylindrical wall 3 is connected to the upper part of the cylindrical wall to form an annular box groove 3a between the open end of the cylindrical wall and the outer cylindrical wall.

[0059] In an optional implementation, the copper alloy sheet parts are in sheet form and the material is a heat-treatable copper alloy.

[0060] In an optional embodiment, the heat treatment box, consisting of a box body 1 and a box cover 2, is made of, for example, 1Cr18Ni9Ti steel plate with a thickness of 5mm, and the box body and box cover have good sealing performance.

[0061] In an optional implementation, the rack 4 is made of 1Cr18Ni9Ti bar with a diameter of 5mm. It is placed vertically for good stability. The rack size is 50mm smaller than the inner diameter of the heat treatment box to facilitate rack placement and retrieval.

[0062] In an optional implementation, the parts vertically suspended on the rack 4 are spaced ≥10mm apart. The purpose is to ensure that the upper and lower surface temperatures of the parts at the same location are consistent during heating and cooling, thus minimizing part deformation.

[0063] In an optional implementation, the rack containing the parts is placed inside the heat treatment chamber. The purpose is to allow the parts to be heated in a closed environment within the heat treatment chamber, while minimizing heat loss during the transfer process, thus ensuring that the parts are ultimately free from oxidation and meet performance standards.

[0064] In an optional implementation, the fine sand used as filler is artificial sand with a particle diameter of less than 0.25 mm. Clean fine sand is placed into the annular groove 3a until the height of the fine sand is basically flush with the upper edge of the annular groove. The purpose is to use fine sand to isolate the parts from the circulation of air inside the furnace, ensuring that the surface of the parts does not oxidize during heating.

[0065] In an optional implementation, the box-type resistance air furnace is a Class III (GJB 509B) heating furnace. The equipment meets the required precision and can process copper alloy sheet parts.

[0066] In an optional implementation, the purpose of horizontally transferring the part to the top of the water tank and vertically immersing it in the water is to minimize shaking during the transfer process, ensure consistent surface temperature at the same location during cooling, and minimize deformation of the part during structural transformation.

[0067] The heat treatment method for copper alloy sheet parts provided in this invention includes solution treatment and aging treatment. A self-developed material rack and heat treatment chamber are used. The method involves cleaning the copper alloy sheet parts, heat treatment chamber, and material rack; binding the parts; vertically suspending them on the material rack; placing the material rack inside the heat treatment chamber; covering the chamber; sealing the chamber with clean filler (e.g., fine sand); and placing the heat treatment chamber in a box-type resistance air furnace for solution treatment and aging treatment. After solution treatment and aging treatment, water cooling is performed, followed by air cooling. This heat treatment method can be used for heat treatment of copper alloy sheet parts, resulting in parts that are oxidation-free, have high strength, and minimal deformation after heat treatment, meeting product size and performance requirements. Furthermore, the method is simple to operate, and the heat treatment chamber and material rack used are simple in structure, reusable, and low in cost. Verification has shown that the heat-treated copper alloy sheet parts are oxidation-free, have high strength, and minimal deformation, meeting the size and performance requirements of the copper alloy sheet parts. Furthermore, in the heat treatment method provided by this invention, the charcoal placed in the heat treatment chamber before the solution treatment can react with a small amount of oxygen in the chamber at high temperature, preventing the oxygen from reacting with the surface of the parts to form an oxide layer. Moreover, in the process of implementing the solution treatment method, by placing the heat treatment chamber in an air furnace, the heat treatment chamber is in the atmospheric environment of the air furnace, and the entire process does not require the introduction of gas or the control of gas parameters. Furthermore, in the process of implementing the aging treatment method, by placing the heat treatment chamber in an air furnace, the heat treatment chamber is in the atmospheric environment of the air furnace, and the entire process does not require the introduction of gas or the control of gas parameters.

[0068] The following describes the implementation of the heat treatment method for copper alloy sheet parts provided in the embodiments of the present invention through some specific examples.

[0069] Example 1

[0070] This embodiment provides a heat treatment method for copper alloy sheet parts. The heat treatment method includes solution treatment and aging treatment, and specifically includes the following steps:

[0071] Step 1: Clean the copper alloy sheet parts, heat treatment box and rack with cleaning agent and dry them with compressed air to ensure that the surface is free of oil and other residues after cleaning.

[0072] Specifically, step 1 includes: wiping the copper alloy sheet parts, the heat treatment chamber shown in Figure 3, and... with cotton yarn soaked in 5503 cleaning agent. Figure 1 The material rack 4 shown is wiped clean and then dried with compressed air. The cleaned surface is then wiped with a white fine yarn glove. The white fine yarn glove is visually inspected and found to be free of oil and other residues.

[0073] Step 2: Bind the copper alloy sheet parts with Φ0.8 double-strand iron wire (without plating) and hang them vertically. Figure 2 On the rack shown, the parts are spaced ≥10mm apart.

[0074] Specifically, step 2 includes: after binding the copper alloy plate parts, using the excess iron wire to straighten the iron wire upwards along the plate surface of the parts, and then hanging the iron wire end on the material rack. The parts are spaced ≥10mm apart, and the parts must not come into contact with the heat treatment box or the material rack.

[0075] Step 3: Place the rack containing the parts into the heat treatment chamber (area 1 in Figure 3), close the chamber lid (area 2 in Figure 3), and put clean fine sand into the annular groove (area 3a in Figure 3) until the sand level is basically flush with the upper edge of the chamber seam.

[0076] Specifically, step 3 includes: wearing clean gloves, placing the rack containing the parts into the heat treatment chamber by hand, and using clean, fine sand that has been dried.

[0077] Step 4: Place the heat treatment box containing the parts into a box-type resistance air furnace for solution treatment and heat preservation.

[0078] Specifically, step 4 includes: after the equipment reaches the set temperature, turn off the heating power, open the furnace door, put the heat treatment box containing the parts into the box-type resistance air furnace (GJB 509B III type), close the furnace door, turn on the heating power, keep it at the required temperature for a period of time, turn off the heating power, open the furnace door, take the heat treatment box out of the furnace, and place it next to the water tank.

[0079] Step 5: Use an iron tool to open the box lid, and use an iron hook to lift the rack containing the parts for cooling (transfer it horizontally above the water tank, place it vertically in the water, and continue for 1 minute). Then lift the rack out, unload the parts, and immediately dry the parts with compressed air.

[0080] Specifically, step 5 includes: cutting the wire with pliers and removing the parts while wearing clean gloves.

[0081] Step 6: Use Φ0.8 double-strand iron wire without plating to bind the copper alloy plate parts and hang them vertically on the rack, with the parts spaced ≥10mm apart.

[0082] Specifically, step 6 includes: after binding the copper alloy plate parts, using the excess wire to straighten the wire upwards along the plate surface of the parts, and then hanging the wire end on the rack. The parts should be spaced ≥10mm apart, and the parts should not come into contact with the heat treatment box or the rack.

[0083] Step 7: Place the rack containing the parts into the heat treatment chamber, close the lid, and put clean fine sand into the seams of the chamber until the sand level is basically flush with the top edge of the seams.

[0084] Specifically, step 7 includes: wearing clean gloves, placing the rack containing the parts into the heat treatment chamber by hand, and using clean, fine sand that has been dried.

[0085] Step 8: Place the heat treatment box containing the parts into the box-type resistance air furnace for aging and heat preservation.

[0086] Specifically, step 8 includes: after the equipment reaches the set temperature, turn off the heating power, open the furnace door, put the heat treatment box containing the parts into the box-type resistance air furnace (GJB 509B III type), close the furnace door, turn on the heating power, keep it at the required temperature for a period of time, turn off the heating power, open the furnace door, take the heat treatment box out of the furnace, and place it next to the water tank.

[0087] Step 9: Use an iron tool to open the box lid, and use an iron hook to lift the rack containing the parts for cooling (place it on the ground in a safe area to cool in room temperature air). After cooling, remove the parts.

[0088] Specifically, step 9 includes: cutting the wire with pliers and removing the parts while wearing clean gloves.

[0089] After solution treatment and aging, copper alloy sheet parts have no oxidation on the surface, high material strength, and small deformation, which can meet the product size and performance requirements.

[0090] Example 2

[0091] The design requirements for a certain chromium bronze QCr0.5 rotor end plate part are: hardness HV not less than 110HV0.5, tensile strength Rm ≥ 350MPa, and elongation after fracture A50mm ≥ 18%. Heat treatment is required for the XX batch of chromium bronze QCr0.5 rotor end plate parts. The part dimensions are as follows: Figure 2 As shown, the material is a heat-treatable copper alloy with a thickness of 1.5 mm. The tensile test specimens are processed according to GB / T228.1, the material standard is Q / YS007-2021, and a box-type resistance air furnace (GJB509BⅢ type) is selected for heat treatment.

[0092] Step 1: Wipe the rotor end plate parts, the heat treatment box shown in Figure 3, and the part with cotton yarn soaked in 5503 cleaning agent. Figure 1 The material rack shown is wiped clean and then dried with compressed air. The cleaned surface is then wiped with a white fine yarn glove. The white fine yarn glove is visually inspected and found to be free of oil and other residues.

[0093] Step 2: After binding the rotor end plate parts with Φ0.8 double-strand iron wire without plating, straighten the excess wire along the plate surface of the parts by pulling it upwards. Then hang the wire ends on the rack, ensuring that the parts are spaced at least 10mm apart and do not contact the heat treatment chamber or the rack. Hang the parts vertically. Figure 1 On the material rack shown.

[0094] Step 3: Wearing clean gloves, place the rack containing the parts into the heat treatment chamber 1 (area marked 1 in Figure 3) by hand, close the chamber lid 2 (area marked 2 in Figure 3), and put clean fine sand into the annular trough ( Figure 1 At area 3a, continue until the sand level is roughly level with the top edge of the seam.

[0095] Step 4: After the equipment reaches the set temperature, place the heat treatment box containing the parts into a box-type resistance air furnace (GJB509BⅢ type) for solution treatment and heat preservation process at a temperature of 960℃±10℃ for 25min~30min.

[0096] Step 5: Use an iron tool to open the box lid, and use an iron hook to lift the rack containing the parts for cooling (transfer it horizontally above the water tank, place it vertically in the water, and continue for 1 minute). Then lift the rack out, unload the parts, and immediately dry the parts with compressed air.

[0097] Step 6: After binding the rotor end plate parts with Φ0.8 double-strand iron wire without plating, straighten the excess wire along the plate surface of the parts by pulling it upwards. Then hang the wire ends on the rack, ensuring that the parts are spaced ≥10mm apart and do not contact the heat treatment box or rack. Hang them vertically. Figure 1 On the material rack shown.

[0098] Step 7: Wearing clean gloves, use your hands to place the rack containing the parts into the heat treatment chamber (area 1 in Figure 3), close the lid (area 2 in Figure 3), and put clean fine sand into the annular groove (area 3 in Figure 3) until the sand level is basically level with the upper edge of the chamber seam.

[0099] Step 8: After the equipment reaches the set temperature, place the heat treatment box containing the parts into a box-type resistance air furnace (GJB509BⅢ type) for aging and heat preservation process at a temperature of 500℃±10℃ for 2h~3h.

[0100] Step 9: Use an iron tool to open the box lid, and use an iron hook to lift the rack containing the parts for cooling (place it on the ground in a safe area to cool in room temperature air). After cooling, remove the parts.

[0101] The XX batch of chromium bronze QCr0.5 rotor end plate parts were heat-treated according to the above steps, and their mechanical properties were sent to the testing department for testing. The surface condition and performance results are shown in Table 1 below.

[0102] Table 1. Statistical Table of Full Processing Results

[0103]

[0104] As shown in Table 1, the rotor end plate parts of batch XX chromium bronze QCr0.5 were heat-treated according to the above steps. The performance of the rotor end plate parts was significantly improved, the surface flatness was good, the metallographic structure of the parts was free of oxidation, the surface hardness HV was (126~130)HV0.5, the tensile strength Rm was (379~386)MPa, and the elongation after fracture A50mm was (28.3~29.5)%, which meets the design requirements of surface hardness HV not less than 110HV0.5, tensile strength Rm ≥ 350MPa, and elongation after fracture A50mm ≥ 18%.

[0105] After multiple verifications of different products and batches, this heat treatment method can significantly improve performance, resulting in good surface flatness, no oxidation on the part surface, and surface hardness, tensile strength Rm, and elongation after fracture A50mm that meet the product size and performance requirements.

[0106] While the embodiments disclosed in this invention are as described above, they are merely illustrative of the embodiments to facilitate understanding of the invention and are not intended to limit the invention. Any person skilled in the art to which this invention pertains may make any modifications and variations in the form and details of the implementation without departing from the spirit and scope disclosed herein; however, the scope of patent protection for this invention shall still be determined by the scope defined in the appended claims.

Claims

1. A heat treatment method for copper alloy sheet parts, characterized in that, include: Step 1: Clean the copper alloy sheet parts, heat treatment chamber, and rack, and dry them with compressed air; Step 2: Hang at least one copper alloy sheet part vertically in the shelf compartment, with a minimum spacing of 10mm between adjacent parts; Step 3: Place the rack containing the parts into the heat treatment chamber, close the lid, and place filler in the annular groove around the lid until the filler is roughly level with the upper edge of the annular groove; charcoal is also placed in the heat treatment chamber. Step 4, solution treatment, includes: placing the heat treatment box containing the parts and rack into an air furnace for solution treatment. The heating temperature and holding time in the solution treatment are determined according to the material of the parts. Step 5: Open the box cover, take out the rack containing the parts and put it into water to cool. After cooling, lift out the rack and remove the parts. Use compressed air to dry the parts. Step 6: After solution treatment and drying, the copper alloy sheet parts are vertically suspended in the partition of the rack, with a minimum spacing of 10mm between adjacent parts. Step 7: Place the rack containing the parts into the heat treatment chamber, close the lid, and place filler in the annular groove around the lid until the height of the filler is basically flush with the upper edge of the annular groove. Step 8, aging treatment, includes: placing the heat treatment box containing the parts and racks into an air furnace for aging treatment. The heating temperature and holding time during the aging treatment are determined according to the material of the parts. Step 9: Open the box cover, take out the rack containing the parts and cool it in the air. After cooling, lift the rack out and unload the parts.

2. The heat treatment method for copper alloy sheet parts according to claim 1, characterized in that, The material rack (4) is configured as a column frame structure. The material rack (4) includes a rack bottom and a rack top arranged in parallel, and a support column connected between the rack bottom and the rack top. Multiple partitions are arranged in parallel on the rack top for vertically placing copper alloy plate parts into the material rack and separating them through the partitions. The dimensions of the rack (4) are set such that after the bottom of the rack (4) is placed into the heat treatment box, all other structures of the rack (4) except the bottom are at least 50mm away from the inner wall of the heat treatment box.

3. The heat treatment method for copper alloy sheet parts according to claim 1, characterized in that, The heat treatment box includes: a cylindrical box body (1) with one end open and a box cover (2). An outer cylindrical wall (3) extends from the outer side of the opening end of the cylindrical box body (1) along the perimeter of the cylindrical wall, and the bottom end face of the outer cylindrical wall (3) is connected to the upper part of the cylindrical wall to form an annular box groove (3a) between the opening end of the cylindrical wall and the outer cylindrical wall.

4. The heat treatment method for copper alloy sheet parts according to any one of claims 1 to 3, characterized in that, In step 4, the heat treatment box containing charcoal, parts and material racks is placed in an air furnace to solidify the parts. The charcoal is used to react with a small amount of oxygen in the box at high temperature to prevent the oxygen from reacting with the surface of the parts to form an oxide layer.

5. The heat treatment method for copper alloy sheet parts according to any one of claims 1 to 3, characterized in that, The cooling method in step 5 is to use a hook to lift the rack containing the parts, transfer it horizontally to the top of the water tank, and place it vertically into the water for a preset time.

6. The heat treatment method for copper alloy sheet parts according to any one of claims 1 to 3, characterized in that, In steps 2 and 6, the copper alloy sheet parts are tied together with unplated iron wire and then vertically suspended in the partition of the material rack.

7. The heat treatment method for copper alloy sheet parts according to any one of claims 1 to 3, characterized in that, In step 9, the rack containing the parts is lifted with a hook and placed on the ground in a safe area to cool in room temperature air.

8. The heat treatment method for copper alloy sheet parts according to any one of claims 1 to 3, characterized in that, In steps 3 and 7, fine sand is filled into the annular groove around the box cover as a filler. The fine sand is artificial sand with a particle diameter of less than 0.25 mm. The fine sand is used to isolate the parts from the circulation of air inside the furnace, ensuring that the surface of the parts does not oxidize when heated.

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