Refrigerant valve and method of manufacturing the same

Abstract

The refrigerant valve comprises a static part and a moving part, the moving part is at least partially located in the static part, the moving part can move relative to the static part to control the communication between different valve ports or the refrigerant flow regulation, the static part has an inner cavity, the inner cavity can be used for the circulation of refrigerant, and the material of at least one of the static part and the moving part is an alloy material; the metallographic structure of the alloy material comprises a beta phase and free lead points, wherein the area ratio of the beta phase is greater than 90%; the application also provides a manufacturing method of the refrigerant valve; in the application, the metallographic structure of at least one of the static part and the moving part takes the beta phase as a matrix phase, and lead is distributed in the form of free state on the intracrystalline and grain boundary of the alloy material, thereby improving the cold and hot impact resistance of the refrigerant valve, enabling the refrigerant valve to withstand the collision of gas-liquid two-phase refrigerant for a long time, and further improving the service life of the refrigerant valve.

Description

Technical Field

[0001] This application belongs to the technical field of refrigerant fluid control devices, specifically relating to a refrigerant valve and its manufacturing method. Background Technology

[0002] Refrigerant valves are mainly used in air conditioning, refrigeration equipment, and thermal management systems to control and regulate the flow of refrigerant. Components within the refrigerant valve, such as the valve body, valve seat, valve stem, and valve core, are in constant contact with the refrigerant. In the thermal management system, the refrigerant exists in two constantly changing phases: gaseous and liquid. The system experiences significant pressure differences (0-4.5 MPa) and temperature variations (-30℃ to 120℃). Therefore, the refrigerant undergoes repeated phase changes between these two states. These constantly changing gaseous and liquid phases collide and compress with the refrigerant valve, causing long-term damage and reducing its lifespan. Summary of the Invention

[0003] The purpose of this application is to provide a refrigerant valve that can withstand the collision of gas and liquid two-phase refrigerant for a long time and has excellent resistance to thermal shock of refrigerant.

[0004] A refrigerant valve includes a stationary part and a movable part, wherein the movable part is at least partially located within the stationary part and is movable relative to the stationary part to control the connection between different valve ports or to regulate the refrigerant flow rate. The stationary part has an inner cavity for the flow of refrigerant, and at least one of the stationary part and the movable part is made of an alloy material.

[0005] The alloy material comprises a β phase and free lead particles, wherein the area of ​​the β phase is greater than 90%.

[0006] In this application, at least one of the stationary part and the moving part is made of an alloy material. The metallographic structure of the alloy material contains an area ratio greater than 90%, with the β phase as the matrix phase. Lead is distributed in a free state within the grains and grain boundaries of the alloy material, which improves the refrigerant valve's resistance to thermal shock from the refrigerant, enabling the refrigerant valve to withstand the collision of gas and liquid two-phase refrigerant for a long time, thereby improving the service life of the refrigerant valve.

[0007] This application also provides a method for manufacturing a refrigerant valve. The refrigerant valve includes a stationary part and a moving part. The moving part is at least partially located within the stationary part. The moving part is movable relative to the stationary part to control the connection between different valve ports or to regulate the refrigerant flow. The stationary part has an inner cavity that can be used for the flow of refrigerant. The method for manufacturing at least one of the stationary part and the moving part includes the following steps:

[0008] Provide metal raw materials;

[0009] The metal raw material is placed in a furnace and smelted to form an alloy melt;

[0010] The alloy melt is cast into an alloy rod;

[0011] The alloy rod is hot-forged and heat-treated.

[0012] The heat-treated alloy comprises a β phase and free lead particles, wherein the area of ​​the β phase is greater than 90%.

[0013] The alloy comprises 0.11wt%-0.9wt% tin, 48wt%-55wt% copper, 1.5wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.3wt%-2.0wt% nickel, and 35wt%-44wt% zinc; the heat treatment temperature is 450℃-600℃, and the heat treatment time is 1-3h.

[0014] This application uses a specific amount of tin, copper, lead, manganese, nickel and nickel compounded together, and combined with a manufacturing process under specific conditions, to obtain an alloy material for the refrigerant valve containing a β phase with an area ratio greater than 90%. With the β phase as the matrix phase, lead is distributed in a free state within the grains and grain boundaries of the alloy material, which improves the refrigerant valve's resistance to thermal shock from the refrigerant, enabling the refrigerant valve to withstand the collision of gas and liquid two-phase refrigerant for a long time, thereby improving the service life of the refrigerant valve. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of one embodiment of the refrigerant valve in this application;

[0016] Figure 2 for Figure 1 A schematic diagram of the cross-sectional structure of the BB plane of the intermediate refrigerant valve;

[0017] Figure 3 for Figure 1 A schematic diagram of the cross-sectional structure of the AA plane of the intermediate refrigerant valve;

[0018] Figure 4 This is a cross-sectional structural schematic diagram of another embodiment of the refrigerant valve in this application;

[0019] Figure 5 This is a flowchart illustrating the manufacturing process of the refrigerant valve in this application;

[0020] Figure 6 This is a metallographic image of the refrigerant valve body in Example 12 of this application;

[0021] Figure 7 This is a metallographic image of the refrigerant valve body in Example 17 of this application;

[0022] Figure 8 This is a metallographic image of the refrigerant valve body in Example 18 of this application. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be described below in conjunction with the embodiments of this application.

[0024] Because refrigerant systems typically contain high-pressure gases, such as refrigerant (with a pressure range of 0-4.5 MPa), refrigerant valves need to withstand high pressures to ensure the safe and stable operation of the system. Furthermore, the operating temperature range of refrigerant valves in refrigerant systems is -30℃ to 120℃, a wide temperature range, requiring valve components to withstand both low and high temperatures. The gas-liquid two-phase change of the refrigerant causes pressure variations; in some applications, the refrigerant valve withstands higher pressures, while in others, it withstands lower refrigerant pressures. Therefore, refrigerant valves not only need to withstand high fluid pressures but also... The refrigerant valve requires high-pressure and even alternating temperature resistance, making it more demanding than commonly used alloy materials. It must withstand not only high pressure but also alternating pressure and temperature, and the thermal shock of the refrigerant. During refrigeration, the valve may operate in low-temperature environments, requiring the alloy material to possess excellent low-temperature toughness to prevent brittle fracture or seal failure. Furthermore, the refrigerant in the system and moisture in the environment can cause corrosion; therefore, the alloy material must exhibit excellent resistance to stress corrosion to ensure long-term stable valve operation.

[0025] In related technologies, brass is commonly used as the material for refrigerant valves. Since brass is a Cu-Zn alloy, according to the phase composition of the Cu-Zn binary system, Cu-Zn includes α, β, and γ phases. In Cu-Zn alloys, the α phase improves plasticity, allowing for both cold and hot working, and possesses good weldability. The β phase is a body-centered cubic solid solution based on the electron compound CuZn, exhibiting low plasticity, being hard and brittle, making cold working difficult, but suitable for hot working. The γ phase is a complex cubic solid solution based on the electron compound Cu5Zn8, also hard and brittle, making pressure processing difficult. The proportions of α, β, and γ phases in brass significantly influence its performance. In related technologies, the phase structure of brass materials for refrigerant valves is mostly composed of α and β phases, with a small amount of γ phase. However, these brass materials also have some shortcomings. For example, under certain environments, zinc in brass may selectively dissolve, leading to material degradation. Zinc dezincification occurs on the surface of the material, reducing its strength and sealing performance. Under the combined action of high stress and corrosive media, brass components may experience stress corrosion cracking (SCC), leading to component failure. This not only affects the service life of refrigerant valves but may also seriously impact the safety and stability of air conditioning, refrigeration equipment, and heat pump systems. Furthermore, the strength of this copper alloy may decrease at high temperatures, making it unsuitable for certain high-temperature operating conditions. While these brasses possess good strength and hardness, meeting the mechanical performance requirements of some refrigerant valves, such as air conditioning shut-off valves, their strength and hardness may be insufficient under high-pressure operating environments, making them prone to deformation and wear. Moreover, due to their poor plasticity or toughness, under harsh operating conditions, brass components or their mating parts may experience stress corrosion cracking. If brass cannot achieve a balance between strength or hardness and plasticity or toughness, the service life of the refrigerant valve will be shortened.

[0026] This application provides a refrigerant valve, including a stationary part 1 and a moving part 7. The moving part 7 is at least partially located within the stationary part 1 and can move relative to the stationary part 1 to control the connection between different valve ports or regulate the refrigerant flow. The stationary part 1 has an inner cavity 114 that can be used to flow refrigerant. At least one of the stationary part 1 and the moving part 7 is made of an alloy material. The alloy material includes a β phase and free lead particles, wherein the area of ​​the β phase is greater than 90%.

[0027] In this application, at least one of the stationary part and the moving part is made of an alloy material. The metallographic structure of the alloy material contains an area ratio greater than 90%, with the β phase as the matrix phase. Lead is distributed in a free state within the grains and grain boundaries of the alloy material, which improves the refrigerant valve's resistance to thermal shock from the refrigerant, enabling the refrigerant valve to withstand the collision of gas and liquid two-phase refrigerant for a long time, thereby improving the service life of the refrigerant valve.

[0028] It should be noted that the β phase in this application was calculated using electron backscatter diffraction (EBSD) technology. The β phase is a body-centered cubic solid solution with CuZn as the matrix, and its area percentage is greater than 90%. Furthermore, the area percentage of the β phase is 91-99%, and can be selected from 91.1%, 91.5%, 92%, 92.5%, 93%, 93.5%, 93.8%, 94%, 94.3%, 94.5%, 94.7%, 95%, 95.1%, 95.3%, 95.5%, 95.7%, 95.8%, 96%, 96.5%, 96.8%, 97.1%, 97.7%, 98%, 98.1%, 98.3%, 98.4%, 98%, and 98%, respectively. The concentrations of lead in the copper alloy are 0.5% and 98.7%, or other values ​​within this range. The remaining portion of the metallographic structure of the copper alloy includes lead particles accounting for 1-3% of the total area, which can be selected from 1.3%, 1.5%, 1.8%, 2%, 2.1%, 2.2%, 2.3%, 2.5%, 24.7%, and 2.8%, or other values ​​within this range. In this application, the β phase is the main matrix phase, containing a small amount of lead particles. Lead is distributed in a free state within the grains and at the grain boundaries of the copper alloy, giving it good machinability and wear resistance. This also improves the stress corrosion resistance, thermal shock resistance, and mechanical properties of the refrigerant valve, allowing it to maintain a long service life even under high temperature and high pressure conditions. The grain size of the copper alloy in the refrigerant valve is tested according to GB / T6394-2017 "Metallic Material Grain Size Determination Method," and the average grain size of the copper alloy is 50-250 μm.

[0029] refer to Figure 1 and Figure 2 As shown, in some embodiments, the stationary part 1 includes a valve body 11, the valve body 11 being made of the alloy material mentioned above, the moving part 7 including a valve stem (not shown), the valve body 11 having a first cavity 111, the inner cavity 114 including the first cavity 111, the valve stem being at least partially located in the first cavity 111, the valve body 11 and the valve stem being threadedly connected, the refrigerant valve including at least two valve ports, the refrigerant valve including a drive part, the drive part being capable of driving the valve stem to move to control the on / off state between at least two valve ports.

[0030] In some embodiments, the refrigerant valve includes a first connecting pipe 5, a second connecting pipe 4, a first valve cap 13, and a connecting pipe nut 14. The first connecting pipe 5 is fixedly connected to or integrally formed with the valve body 11, and the second connecting pipe 4 is integrally formed with the valve body 11. The first connecting pipe 5 has a first channel 110, and the second connecting pipe 4 has a second channel 120. The valve stem 71 can control fluid isolation or fluid communication between the first channel 110 and the second channel 120. The first valve cap 13 and the connecting pipe nut 14 are both configured to cooperate with the valve body 1. At least one of the valve body 1, the valve cap 13, and the connecting pipe nut 14 is made of the alloy material described above.

[0031] In some embodiments, the valve stem is provided with an external thread, and the inner wall of the valve body 11 is provided with an internal thread that mates with the external thread of the valve stem. Under the action of the threaded pair, it moves up and down in the inner cavity of the valve body 11 to close or connect the first channel 110 and the second channel 120. The inner wall of the valve body 11 is provided with a thread that mates with the first valve cap 13 and the connecting nut 14.

[0032] In some embodiments, the valve body 11 has a valve port 3, and the first channel 110 and the second channel 120 are connected through the valve port 3. The valve stem is at least partially disposed in the first cavity 111 and can move up and down along the inner cavity of the valve body 11 to open or close the valve port 3, thereby connecting or disconnecting the first channel 110 and the second channel 120. Further, when the valve stem moves down to the limit position, it abuts against the valve port 3, thereby closing the valve port 3. At this time, the refrigerant valve is in the closed state. In some embodiments, the refrigerant valve also includes a second valve cap 2, which is connected to the valve body 11, such as by a threaded connection.

[0033] refer to Figure 4 As shown, in some embodiments, the stationary part 1 includes a valve body 11 made of the copper alloy mentioned above, and the moving part 7 includes a valve core 102. The valve body 11 has a first cavity 111, and the valve core 102 is at least partially located in the first cavity 111. The first cavity 111 is capable of circulating refrigerant. The valve core 102 has a second cavity 103. The refrigerant valve has a first state in which the first cavity 111 and the second cavity 103 are in communication.

[0034] In some embodiments, the refrigerant valve also has a second state in which the first chamber 111 and the second chamber 103 are closed. The refrigerant valve also includes a drive unit 104, which is fixedly connected to the valve core 102. The drive unit can drive the valve core 102 to rotate to control the opening and closing between the first chamber 111 and the second chamber 103. That is, the drive unit 104 can control the first chamber 111 and the second chamber 104 to be connected or closed, that is, the drive unit 104 can control the refrigerant valve to be in the first state or the second state.

[0035] refer to Figure 5 As shown, this application also provides a method for manufacturing a refrigerant valve, comprising the following steps:

[0036] Provide metal raw materials;

[0037] Metal raw materials are placed in a furnace and smelted to form an alloy melt;

[0038] The alloy melt is cast into an alloy rod;

[0039] The alloy rod is hot-forged and heat-treated.

[0040] In some embodiments, the alloy is a copper alloy comprising 0.11wt%-0.9wt% tin (Sn), 48-55wt% copper (Cu), 1.5wt%-4.0wt% lead (Pb), 1.5wt%-4.5wt% manganese (Mn), 0.3wt%-2.0wt% nickel (Ni), and 35wt%-44wt% zinc (Zn).

[0041] In this application, a copper alloy containing specific amounts of tin, copper, lead, manganese, nickel and zinc is used in combination. The specific amounts of tin, copper, lead, manganese, nickel and zinc, combined with specific manufacturing process conditions, can optimize the grain boundary structure in the copper alloy, reduce the accumulation of grain boundary impurities, and improve the stress corrosion resistance of the copper alloy used in refrigerant valves to gas-liquid two-phase refrigerants.

[0042] In some embodiments, the tin content in the copper alloy is 0.11wt%-0.9wt%, specifically selectable as 0.12wt%, 0.13wt%, 0.14wt%, 0.15wt%, 0.16wt%, 0.17wt%, 0.18wt%, 0.19wt%, 0.20wt%, 0.21wt%, 0.22wt%, 0.23wt%, 0.24wt%, 0.25wt%, 0.26wt%, 0.27wt%, 0.28wt%, 0.29wt%, 0.30wt%, 0.31wt%, and 0.32wt%. The percentages are 0.33wt%, 0.34wt%, 0.35wt%, 0.36wt%, 0.37wt%, 0.38wt%, 0.39wt%, 0.4wt%, 0.42wt%, 0.45wt%, 0.5wt%, 0.55wt%, 0.6wt%, 0.62wt%, 0.64wt%, 0.68wt%, 0.7wt%, 0.75wt%, 0.8wt%, 0.85wt%, and 0.88wt%. Other values ​​within this range can be selected as needed and are not limited here. Furthermore, the tin content is 0.11wt%. The tin content ranges from 0.25 wt% to 0.4 wt%, and further, from 0.25 wt% to 0.4 wt%. Adding tin to copper alloys allows it to form solid solutions or compounds with copper, promoting uniform distribution of alloying elements, reducing grain coarsening, and resulting in finer grains. This enhances the ductility and formability of the copper alloy while maintaining high strength. During both cold and hot working, the copper alloy retains good plasticity. Simultaneously, the addition of tin reduces the fracture tendency of the copper alloy during forming, lowers internal stress during processing, and improves its resistance to stress corrosion, contributing to the reduction of copper alloy degradation. In addition to reducing stress corrosion cracking, the addition of tin helps improve the microstructure of copper alloys, making the stress distribution inside the copper alloy more uniform, reducing stress concentration, and thus helping to reduce the generation of cracks during processing and improve the reliability of the forming process. If the tin content is too low, it may not achieve the effect of improving plasticity. On the contrary, if the tin content is too high, on the one hand, the various properties will not be significantly improved, and on the other hand, the cost will increase significantly. Therefore, in this application, the addition of a specific amount of tin to the copper alloy improves the ductility of the copper alloy while maintaining high strength, and at the same time reduces the production cost of the copper alloy.

[0043] In some embodiments, the lead content is 1.5wt%-4.0wt%, specifically 1.7wt%, 1.9wt%, 2.1wt%, 2.3wt%, 2.5wt%, 2.7wt%, 2.9wt%, 3.1wt%, 3.3wt%, 3.4wt%, 3.5wt%, 3.7wt%, 3.8wt%, and 3.9wt%. Other values ​​within this range can be selected as needed and are not limited here. Adding lead to copper alloys can improve their machinability. If the lead content is too low or too high, it will not effectively improve the machinability of copper alloys or maintain other properties such as mechanical properties, hot forging properties, and stress corrosion resistance. Furthermore, the lead content is selected from 3.0wt%-4.0wt%.

[0044] In some embodiments, the manganese content is 1.5wt%-4.5wt%, specifically 1.7wt%, 1.9wt%, 2.1wt%, 2.3wt%, 2.5wt%, 2.7wt%, 2.9wt%, 3.1wt%, 3.3wt%, 3.5wt%, 3.7wt%, 3.9wt%, 4.1wt%, and 4.3wt%. Other values ​​within this range can be selected as needed and are not limited here. Adding manganese to copper alloys can improve their strength. Too low or too high a manganese content has no significant impact on the mechanical properties of the copper alloy. Furthermore, the manganese content is selected from 2.5wt%-3.5wt%.

[0045] In some embodiments, the nickel content is 0.3wt%-2.0wt%, specifically 0.3wt%, 0.4wt%, 0.5wt%, 0.6wt%, 0.7wt%, 0.8wt%, 1.0wt%, 1.1wt%, 1.2wt%, 1.4wt%, 1.6wt%, 1.7wt%, 1.8wt%, and 1.9wt%. Other values ​​within this range can be selected as needed and are not limited here. Adding nickel to copper alloys can enhance the stability of the passivation film on the copper alloy surface, reducing corrosion from corrosive media. Simultaneously, nickel can form a solid solution in the copper alloy, enhancing its crystal structure, reducing grain coarsening, and effectively improving the strength, hardness, and high-temperature resistance of the copper alloy. Furthermore, nickel can improve the copper alloy's properties by refining the grain structure and strengthening the bonding between crystals. The addition of nickel enhances the hardness and wear resistance of copper alloys. It also strengthens the resistance of copper alloys to stress corrosion in chemical environments (such as ammonia environments), thereby improving their reliability and extending their service life. Nickel improves the fluidity and plasticity of copper alloys, making them easier to form during processing and also giving them better weldability. However, excessively low or high nickel content may reduce the plasticity and stress corrosion resistance of copper alloys. Therefore, selecting a specific nickel content can improve the strength, hardness, and stress corrosion resistance of brass. When choosing the amount of nickel added, it is necessary to balance the relationship between strength and plasticity based on the actual usage environment and processing requirements. An appropriate amount of nickel can usually improve the overall performance of brass without significantly affecting its plasticity. Furthermore, the nickel content is selected from 0.35wt% to 0.8wt%.

[0046] In some embodiments, the copper alloy further includes 0.01wt%-1.5wt% aluminum (Al), specifically selected from 0.2wt%, 0.5wt%, 0.7wt%, 0.8wt%, 0.9wt%, 1.1wt%, 1.2wt%, 1.3wt%, and 1.4wt%, or other values ​​within this range as needed, without limitation here; furthermore, the aluminum content is 0.01wt%-0.5wt%; adding a specific amount of aluminum to the copper alloy can refine the grain size of the copper alloy, improve the mechanical properties of the copper alloy, and at the same time improve the processing performance of the copper alloy.

[0047] In some embodiments, the copper alloy also includes iron; adding iron (Fe) to the aforementioned copper alloy can improve the mechanical properties of the copper alloy, giving it higher strength and hardness; furthermore, the iron content is ≤1.5wt%, specifically selected from 0wt%, 0.2wt%, 0.5wt%, 0.7wt%, 0.8wt%, 0.9wt%, 1.1wt%, 1.2wt%, 1.3wt%, 1.4wt%, or other values ​​within this range as needed, without limitation here; furthermore, the iron content is 0.25wt%-1.5wt%; adding a specific amount of iron to the copper alloy can refine the grain size of the copper alloy, improve the mechanical properties of the copper alloy, and at the same time improve the machinability of the copper alloy.

[0048] In some embodiments, the copper alloy further includes ≤0.1wt% boron (B), specifically selected from 0.001wt%, 0.002wt%, 0.005wt%, 0.01wt%, 0.015wt%, 0.02wt%, 0.025wt%, 0.03wt%, 0.035wt%, 0.04wt%, 0.05wt%, 0.06wt%, 0.07wt%, 0.08wt%, and 0.09wt%, or other values ​​within this range as needed, without limitation here; furthermore, the boron content is 0.001wt%-0.1wt%; adding boron to the copper alloy mentioned above can refine the grain size in the copper alloy, and at the same time improve the plasticity of the copper alloy, giving the copper alloy better comprehensive properties.

[0049] In this application, the copper content in the copper alloy is 48wt%-55wt%, and the copper content is not higher than 55wt%. Further, in some embodiments, the copper content is 48wt%-53wt%, specifically selected from 48wt%, 48.5wt%, 48.7wt%, 49wt%, 49.3wt%, 49.5wt%, 49.8wt%, 50wt%, 50.2wt%, 50.4wt%, 50.7wt%, 50.8wt%, 50.9wt%, 51wt%, and 51wt%. 0.2wt%, 51.5wt%, 51.6wt%, 51.7wt%, 51.8wt%, 52wt%, 52.1wt%, 52.2wt%, 52.3wt%, 52.5wt%, 52.7wt%, 52.8wt%, 52.9wt%, and other values ​​within this range can be selected as needed; no specific limitation is imposed here. On the one hand, this can reduce the production cost of copper alloys, which is conducive to the large-scale promotion and application of refrigerant valves. On the other hand, the use of specific contents of copper, lead, manganese, nickel, and tin in combination... This invention can optimize the solid solution structure of copper alloys, improve their plasticity, and reduce the likelihood of cracking. It can also optimize the grain boundary structure, reduce the accumulation of impurities at grain boundaries, and improve the stress corrosion resistance of copper alloys. This allows the copper alloys to maintain a longer service life and higher reliability even under high pressure, high humidity, and corrosive media environments (such as ammonia). Furthermore, the copper alloys provided by this application exhibit high strength and hardness. In addition, the design of copper alloy materials in this application not only considers the grain refinement effect but also aims to improve the overall performance of the copper alloy, such as mechanical properties, machinability, hot forging properties, resistance to ammonia corrosion, and reduce production costs. Excessive or insufficient use of any element may negatively impact these properties; therefore, experiments and optimization are needed to determine the optimal addition amount. In short, the addition amount of each element in the copper alloy needs to be precisely tested and optimized to find a suitable addition range that maximizes the grain refinement effect while maintaining the optimization of other properties, thereby improving the service life of the refrigerant valve.

[0050] Due to the complex interactions between the strength, hardness, plasticity, and toughness properties of each phase, generally speaking, increasing strength may lead to a decrease in plasticity or toughness. Similarly, increasing hardness may also have an adverse effect on plasticity. If brass cannot achieve a balance between strength or hardness and plasticity or toughness, the service life of the refrigerant valve will be shorter. Therefore, it is necessary to use reasonable material design and manufacturing processes to obtain brass materials that have high strength, high hardness, and good plasticity and toughness, so that they can be better applied to refrigerant valves and improve their service life.

[0051] In some embodiments, the copper alloy comprises: 0.11wt%-0.9wt% tin, 48wt%-55wt% copper, 1.5wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.3wt%-2.0wt% nickel, 35wt%-44wt% zinc, and unavoidable impurities; or, the copper alloy comprises: 0.11wt%-0.9wt% tin, 48wt%-55wt% copper, 1.5wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.001wt%-0.1wt% boron, 0.3wt%-2.0wt% nickel, 35wt%-44wt% zinc, and unavoidable impurities; or, the copper alloy comprises: 0.11wt%-0.9wt% tin, 48wt%-55wt% copper, 1.5wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.1wt%-1.5wt% iron, 0.3wt%-2.0wt% nickel, 35wt%-44wt% zinc, and unavoidable impurities; or, the composition of the copper alloy includes: 0.11wt%-0.9wt% tin, 48wt%-55wt% copper, 1.5wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.1wt%-1.5wt% iron, 0.001wt%-0.1wt% boron, 0.3wt%-2.0wt% nickel, 35wt%-44wt% zinc, and unavoidable impurities. In this application, a copper alloy containing a specific amount of tin, copper, lead, manganese, nickel and zinc is used in combination. The specific amount of tin, copper, lead, manganese, nickel and zinc used in combination can optimize the grain boundary structure in the copper alloy, reduce the accumulation of grain boundary impurities, and improve the stress corrosion resistance of the copper alloy used in refrigerant valves to gas-liquid two-phase refrigerant under specific process manufacturing conditions.

[0052] Further, the copper alloy composition is: 0.11wt%-0.9wt% tin, 48-55wt% copper, 1.5wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.01wt%-0.5wt% aluminum, 0.3wt%-2.0wt% nickel, balance zinc, and unavoidable impurities; or, the copper alloy composition is: 0.11wt%-0.9wt% tin, 48-55wt% copper, 1.5wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.01wt%-0.5wt% aluminum, 0.001wt%-0.1wt% boron, 0.3wt%-2.0wt% nickel, balance zinc, and unavoidable impurities; or, the copper alloy composition is: 0.1 1 wt%-0.9 wt% tin, 48-55 wt% copper, 1.5 wt%-4.0 wt% lead, 1.5 wt%-4.5 wt% manganese, 0.01 wt%-0.5 wt% aluminum, 0.1 wt%-1.5 wt% iron, 0.3 wt%-2.0 wt% nickel, balance zinc and unavoidable impurities; or, the composition of the copper alloy is: 0.11 wt%-0.9 wt% tin, 48-55 wt% copper, 1.5 wt%-4.0 wt% lead, 1.5 wt%-4.5 wt% manganese, 0.01 wt%-0.5 wt% aluminum, 0.1 wt%-1.5 wt% iron, 0.001 wt%-0.1 wt% boron, 0.3 wt%-2.0 wt% nickel, balance zinc and unavoidable impurities. Copper alloys contain specific amounts of tin, copper, lead, manganese, nickel, and zinc. The specific amounts of tin, copper, lead, manganese, nickel, zinc, and / or aluminum and / or iron and / or boron are used in combination with specific manufacturing process conditions to optimize the grain boundary structure in copper alloys, reduce the accumulation of grain boundary impurities, improve the stress corrosion resistance of copper alloys, and at the same time improve the strength, hardness, and plasticity of copper alloys.

[0053] Furthermore, in some embodiments, the copper alloy comprises 0.13wt%-0.4wt% tin, 1.5wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.3wt%-1.5wt% nickel, 48wt%-53wt% copper and 35wt%-45wt% zinc.

[0054] In this application, the copper alloy contains specific amounts of tin, copper, lead, manganese, nickel, and zinc. The combination of these metal elements, along with specific manufacturing process conditions, helps to evenly distribute the alloying elements, reduce grain coarsening in the copper alloy, and the copper alloy used in the refrigerant valve has good toughness or plasticity, which can improve the impact resistance of the gas-liquid two-phase refrigerant.

[0055] In some embodiments, the copper alloy comprises: 0.13wt%-0.4wt% tin, 1.5wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.3wt%-1.5wt% nickel, 48wt%-53wt% copper, 35wt%-45wt% zinc, and unavoidable impurities; or, the copper alloy comprises: 0.13wt%-0.4wt% tin, 3.0wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.3wt%-1.5wt% nickel, 0.25wt%-1.5wt% iron, 48wt%-53wt% copper, 35wt%-45wt% zinc, and unavoidable impurities; or, the copper alloy comprises: 0. 13wt%-0.4wt% tin, 1.5wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.001wt%-0.1wt% boron, 0.3wt%-1.5wt% nickel, 48wt%-53wt% copper, 35wt%-45wt% zinc and unavoidable impurities; or, the composition of the copper alloy includes: 0.13wt%-0.4wt% tin, 1.5wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.001wt%-0.1wt% boron, 0.3wt%-1.5wt% nickel, 0.25wt%-1.5wt% iron, 48wt%-53wt% copper, 35wt%-45wt% zinc and unavoidable impurities. In this application, the copper alloy contains specific amounts of tin, copper, lead, manganese, nickel, and zinc. The combination of these metal elements, along with specific manufacturing processes, helps to evenly distribute the alloying elements, reduce grain coarsening in the copper alloy, and form a metallographic structure with excellent morphology. The copper alloy used in refrigerant valves has good toughness or plasticity, which can improve the impact resistance of gas-liquid two-phase refrigerants.

[0056] Further, in some embodiments, the copper alloy composition is: 0.13wt%-0.4wt% tin, 1.5wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.01wt%-0.5wt% aluminum, 0.3wt%-1.5wt% nickel, 48wt%-53wt% copper, balance zinc, and unavoidable impurities; or, the copper alloy composition is: 0.13wt%-0.4wt% tin, 3.0wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.01wt%-0.5wt% aluminum, 0.3wt%-1.5wt% nickel, 0.25wt%-1.5wt% iron, 48wt%-53wt% copper, balance zinc, and unavoidable impurities; or, the copper alloy composition is: 0 0.13wt%-0.4wt% tin, 1.5wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.01wt%-0.5wt% aluminum, 0.001wt%-0.1wt% boron, 0.3wt%-1.5wt% nickel, 48wt%-53wt% copper, balance zinc and unavoidable impurities; or, the composition of the copper alloy is: 0.13wt%-0.4wt% tin, 1.5wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.01wt%-0.5wt% aluminum, 0.001wt%-0.1wt% boron, 0.3wt%-1.5wt% nickel, 0.25wt%-1.5wt% iron, 48wt%-53wt% copper, balance zinc and unavoidable impurities. In this application, the copper alloy contains specific amounts of tin, copper, lead, manganese, aluminum, nickel, zinc and / or aluminum and / or iron and / or boron. The various metal elements are used in combination and with specific manufacturing processes. The specific amount of tin can form a solid solution or compound with copper, which helps to evenly distribute the alloying elements, reduce grain coarsening of the copper alloy, improve the plasticity of the copper alloy, and at the same time give the copper alloy high strength and hardness.

[0057] This application uses a specific blend of tin, lead, manganese, nickel, copper, and zinc. The elements exhibit a synergistic effect, improving the plasticity of the copper alloy. This allows the copper alloy to exist in both gaseous and liquid phases within the thermal management system. Furthermore, it is less prone to stress corrosion cracking in environments with significant pressure differences (0-4.5 MPa) and extreme temperature variations (-30℃ to 120℃) in the refrigerant, or when used in combination with other materials. It also exhibits good resistance to thermal shock and enhances the copper alloy's resistance to stress corrosion in corrosive media (such as ammonia). This results in a longer service life and higher reliability of the copper alloy even under high pressure, high humidity, and corrosive media conditions (such as ammonia). The copper alloy material of this application also possesses high strength and hardness. Furthermore, the copper alloy material designed in this application exhibits excellent comprehensive properties, such as plasticity, mechanical properties, machinability, hot forging properties, resistance to ammonia corrosion, and low production costs. Excessive or insufficient use of any of the elements may negatively impact these properties; therefore, experiments and optimization are needed to determine the optimal addition amount. In short, the addition amount of each element in the copper alloy requires precise experimentation and optimization to find a suitable addition range that maximizes grain refinement while maintaining other optimized properties, thereby improving the service life of the copper alloy and enabling its broad application prospects in harsh operating environments (high temperature, high pressure, and low temperature). In some embodiments, the copper alloy also includes at least one of ≤1.5wt% iron and ≤0.5wt% aluminum.

[0058] It should be noted that the copper alloys mentioned in this application include, but are not limited to, brass materials; the "wt%" mentioned in this application means mass percentage or weight percentage; "unavoidable impurities" refers to impurity elements contained in the metal raw materials, and their content is the usual content in the metal raw materials; the content of each component of the copper alloy in this application meets the upper and lower limit requirements formula, that is: the upper limit of the content of a single component + the lower limit of the content of other components ≤ 100wt%, and the lower limit of the content of a single component + the upper limit of the content of other components ≥ 100wt%.

[0059] In some embodiments, the method for manufacturing a refrigerant valve includes a step S1 of weighing metal raw materials according to a specified ratio; specifically, in step S1, metal raw materials are weighed according to a specified ratio to obtain the copper alloy composition mentioned above.

[0060] In some embodiments, the method for manufacturing the refrigerant valve further includes step S2, in which metal raw materials are placed in a furnace and melted to form a copper alloy melt; specifically, according to the component ratio, the metal raw materials are first placed in a furnace and heated to melt, and then other remaining components are added in sequence, and the mixture is continuously stirred to ensure that the components are mixed evenly.

[0061] Furthermore, in some embodiments, the heating and melting temperature is 1000℃-1200℃, and the stirring time is 5-10 minutes to ensure that the components are mixed evenly.

[0062] In some embodiments, the manufacturing method of the refrigerant valve further includes step S3, which involves horizontally casting a copper alloy melt into a copper rod. Specifically, in step S3, the copper alloy melt is continuously cast into a copper rod using a horizontal continuous casting device, and the diameter and cooling rate of the copper rod are controlled to obtain a copper rod with a uniform brass structure. Further, in some embodiments, the diameter of the copper rod is 14-40 mm, and the cooling rate is 300-350 °C / s.

[0063] In some embodiments, the manufacturing method of the refrigerant valve further includes step S4, which involves hot forging and machining a copper rod to form the refrigerant valve. Specifically, the copper rod is heated to a hot forging temperature and forged to form a copper part. In some embodiments, before hot forging the copper rod, step S4 further includes cutting the copper rod into appropriate sizes, then adding graphite and stirring it evenly with the copper rod to control the surface roughness of the copper rod between 0.5-2.0 μm. It should be noted that the size of the copper rod, the type of graphite, the stirring equipment, the stirring time, and the stirring speed are not limited here, as long as the target roughness can be achieved.

[0064] Furthermore, in some embodiments, the hot forging temperature is 750℃-800℃, specifically selected from 755℃, 760℃, 770℃, 780℃, 790℃, 795℃, or other data within this range, which is not limited here. The hot forging time is 1-5s, specifically selected from 1s, 2s, 3s, 4s, 5s, or other data within this range, which is not limited here. Through hot forging treatment, the internal structure of the copper parts is further optimized, and the mechanical properties and stress corrosion resistance of the refrigerant valve are improved.

[0065] In some embodiments, after the copper rod is hot-forged, a copper part is formed. Step S4 further includes heat-treating the copper part to eliminate hot forging stress and improve the mechanical properties of the copper part. Further, the heat treatment temperature is 450℃-600℃, specifically selected from 455℃, 460℃, 465℃, 470℃, 480℃, 490℃, 495℃, 500℃, 510℃, 520℃, 530℃, 540℃, 550℃, 560℃, 570℃, 580℃, 590℃, or other data within this range, which are not limited here. The heat treatment time is 1-3 hours.

[0066] In some embodiments, after heat treatment and before machining, step S4 further includes shot peening the heat-treated copper part to remove oxides and burrs from the surface of the copper part and to homogenize the surface roughness of the copper part, so that the surface roughness of the copper part reaches Ra 2.5-4.0μm; then the shot-peened copper part is machined to make various parts of the required shape and size, and assembled to obtain the refrigerant valve; the process parameters of shot peening in this application are not specifically limited, as long as the target roughness can be achieved; this application obtains a copper alloy with excellent comprehensive performance by adopting a suitable process and a specific content of alloy composition, which can then be applied to refrigerant valves with strict material requirements.

[0067] It should be noted that the refrigerant valve mentioned in this application includes, but is not limited to, solenoid valves, expansion valves, ball valves, and shut-off valves. The stationary part includes, but is not limited to, the valve body of the refrigerant valve and other stationary parts in contact with the refrigerant. The moving part includes, but is not limited to, the valve stem, valve core, valve needle, valve cap, nut, and other moving parts in the refrigerant valve and other moving parts in contact with the refrigerant.

[0068] In some embodiments, after the refrigerant valve undergoes an ammonia corrosion resistance test, at least a portion of the surface of the stationary part 1 shows no cracks affecting the sealing performance; the test conditions for the ammonia corrosion resistance test are as follows:

[0069] (a) Apply at least 30-40 N·m of torque to the stationary part 1;

[0070] (b) Prepare an ammonia solution with a concentration of 20-30wt% and place it in a container. Place the stationary part 1 from step (a) above the ammonia solution, ensuring that the stationary part 1 does not come into contact with the ammonia solution. Place it at 20℃-30℃ for 72 hours. The test environment for the ammonia corrosion resistance test is a closed environment, and the volume of the container is 90-105L.

[0071] The refrigerant valves in this application include, but are not limited to, shut-off valves, ball valves, etc., and the fluids include, but are not limited to, refrigerants, including, but are not limited to, R22, R290, R410a, R32, R407C, R454B, R134a, R404A, R448A, R449A, CO2, etc.

[0072] The manufacturing method of the refrigerant valve in this application will be described below with reference to specific implementation methods.

[0073] Example 1

[0074] A method for manufacturing a refrigerant valve includes the following steps:

[0075] S1. Weigh the copper alloy raw materials according to the proportions, wherein the copper alloy raw materials include: 48.8wt% copper, 3.4wt% lead, 3.0wt% manganese, 0.35wt% nickel, 0.2wt% tin, 0.1wt% aluminum, 1.0wt% iron and the balance zinc;

[0076] S2. According to the component ratio, first place the copper in the melting furnace and heat it to 1100℃ to completely melt it. Then add the remaining components in sequence and stir continuously for 10 minutes to ensure that the components are mixed evenly to form a copper alloy melt.

[0077] S3. The copper alloy melt from step S2 is continuously cast into copper rods using a horizontal continuous casting equipment. The diameter of the copper rods is controlled to be 18 mm and the cooling rate is 315℃ / s to obtain copper rods with uniform structure. Then, the copper rods are stirred evenly with natural flake graphite (flake size 0.18 mm, fixed carbon content ≥95wt%) to make the surface roughness of the copper rods reach 1.2 μm.

[0078] S4. Heat the copper rod from step S3 to the hot forging temperature, which is controlled at 750℃. Forge for 2 seconds to form a copper part. Then, place the copper part into a heating device and heat treat it at 550℃ for 2 hours. After heat treatment, perform shot peening to make the surface roughness of the copper part reach 3.5μm. Then, perform machining to make the required shape and size of each component and assemble it to obtain the refrigerant valve.

[0079] Example 2

[0080] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 1, except that in step S1, copper alloy raw materials are weighed according to the proportions, wherein the copper alloy raw materials include: 49.2 wt% copper, 2.9 wt% lead, 2.5 wt% manganese, 0.35 wt% nickel, 0.3 wt% tin, 0.1 wt% aluminum, 1.0 wt% iron and the balance zinc.

[0081] Example 3

[0082] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 1, except that in step S3, the copper alloy melt from step S2 is continuously cast into a copper rod using a horizontal continuous casting equipment, the diameter of the copper rod is controlled to be 20 mm, and the cooling rate is 325 °C / s, so as to obtain a copper rod with uniform structure. Then the copper rod is stirred evenly with natural flake graphite (flake size 0.18 mm, fixed carbon content ≥95 wt%), so that the surface roughness of the copper rod reaches 1.4 μm.

[0083] Example 4

[0084] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 1, except that in step S4, the copper rod in step S3 is heated to the hot forging temperature, which is controlled at 760°C, and forged for 2 seconds to form a copper part. Then, the copper part is placed in a heating device and heat-treated at 500°C for 2 hours. The heat-treated copper part is shot-peened to achieve a surface roughness of 2.8 μm. Then, it is machined to produce the required shape and size of each component, and assembled to obtain the refrigerant valve.

[0085] Example 5

[0086] A method for manufacturing a refrigerant valve includes the following steps:

[0087] S1. Weigh the copper alloy raw materials according to the proportions, wherein the copper alloy raw materials include 51.8wt% copper, 3.6wt% lead, 3.3wt% manganese, 0.7wt% nickel, 0.23wt% tin, 0.17wt% aluminum, 0.85wt% iron and the balance zinc;

[0088] S2. According to the component ratio, first heat the copper in the melting furnace to 1200℃ to completely melt it, then add the remaining components in sequence and stir continuously for 8 minutes to ensure that the components are mixed evenly to form a copper alloy melt.

[0089] S3. The copper alloy melt from step S2 is continuously cast into copper rods using a horizontal continuous casting equipment. The diameter of the copper rods is controlled to be 27 mm and the cooling rate is 300℃ / s to obtain copper rods with uniform structure. Then, the copper rods are stirred evenly with natural flake graphite (flake size 0.18 mm, fixed carbon content ≥95wt%) to make the surface roughness of the copper rods reach 1.6 μm.

[0090] S4. Heat the copper rod from step S3 to the hot forging temperature, which is controlled at 755℃. Forge for 2 seconds to form a copper part. Then, place the copper part into a heating device and heat treat it at 490℃ for 3 hours. After heat treatment, perform shot peening to make the surface roughness of the copper part reach 3.1μm. Then, perform machining to make the required shape and size of each component and assemble it to obtain the refrigerant valve.

[0091] Example 6

[0092] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 5, except that in step S1, copper alloy raw materials are weighed according to the proportions, wherein the copper alloy raw materials include 50.9 wt% copper, 3.2 wt% lead, 3.7 wt% manganese, 0.5 wt% nickel, 0.34 wt% tin, 0.15 wt% aluminum, 0.13 wt% iron and the balance zinc.

[0093] Example 7

[0094] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 5, except that in step S3, the copper alloy melt from step S2 is continuously cast into a copper rod using a horizontal continuous casting device, the diameter of the copper rod is controlled to be 32 mm, and the cooling rate is 324 °C / s, so as to obtain a copper rod with uniform structure. Then the copper rod is stirred evenly with natural flake graphite (flake size 0.18 mm, fixed carbon content ≥95 wt%), so that the surface roughness of the copper rod reaches 1.2 μm.

[0095] Example 8

[0096] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 5, except that in step S4, the copper rod in step S3 is heated to the hot forging temperature, which is controlled at 775°C, and forged for 2 seconds to form a copper part. Then, the copper part is placed in a heating device and heat-treated at 500°C for 3 hours. The heat-treated copper part is shot-peened to achieve a surface roughness of 3.1 μm. Then, it is machined to produce the required shape and size of each component, and assembled to obtain the refrigerant valve.

[0097] Example 9

[0098] A method for manufacturing a refrigerant valve includes the following steps:

[0099] S1. Weigh the copper alloy raw materials according to the proportions, wherein the copper alloy raw materials include 49.8wt% copper, 3.6wt% lead, 3.4wt% manganese, 1.25wt% nickel, 0.15wt% tin, 0.11wt% aluminum, 0.87wt% iron and the balance zinc.

[0100] S2. According to the component ratio, first place the copper in the melting furnace and heat it to 1150℃ to completely melt it. Then add the remaining components in sequence and stir continuously for 10 minutes to ensure that the components are mixed evenly to form a copper alloy melt.

[0101] S3. The copper alloy melt from step S2 is continuously cast into copper rods using a horizontal continuous casting equipment. The diameter of the copper rods is controlled to be 19 mm and the cooling rate is 330℃ / s to obtain copper rods with uniform structure. Then, the copper rods are stirred evenly with natural flake graphite (flake size 0.18 mm, fixed carbon content ≥95wt%) to make the surface roughness of the copper rods reach 0.8 μm.

[0102] S4. Heat the copper rod from step S3 to the hot forging temperature, which is controlled at 785℃. Forge for 3 seconds to form a copper part. Then, place the copper part into a heating device and heat it at 505℃ for 2 hours. After heat treatment, the copper part is shot peened to achieve a surface roughness of 3.6μm. Then, it is machined to produce the required shapes and sizes of various parts and assembled to obtain the refrigerant valve.

[0103] Example 10

[0104] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 9, except that in step S1, copper alloy raw materials are weighed according to the proportion, wherein the copper alloy raw materials include 50.5 wt% copper, 3.25 wt% lead, 2.9 wt% manganese, 0.75 wt% nickel, 0.3 wt% tin, 0.08 wt% aluminum, 1.2 wt% iron and the balance zinc.

[0105] Example 11

[0106] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 9, except that in step S3, the copper alloy melt from step S2 is continuously cast into a copper rod using a horizontal continuous casting device, the diameter of the copper rod is controlled to be 21 mm, and the cooling rate is 328 °C / s, so as to obtain a copper rod with uniform structure. Then, the copper rod is stirred evenly with natural flake graphite (flake size 0.18 mm, fixed carbon content ≥95 wt%) so that the surface roughness of the copper rod reaches 1.3 μm.

[0107] Example 12

[0108] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 9, except that in step S4, the copper rod in step S3 is heated to the hot forging temperature, which is controlled at 765°C, and forged for 3 seconds to form a copper part. Then, the copper part is placed in a heating device and heated at 600°C for 1 hour. The heated copper part is shot peened to achieve a surface roughness of 3.8 μm. Then, it is machined to produce the required shape and size of each component, and assembled to obtain the refrigerant valve.

[0109] Example 13

[0110] A method for manufacturing a refrigerant valve includes the following steps:

[0111] S1. Weigh the copper alloy raw materials according to the proportions, wherein the copper alloy raw materials include 49.7wt% copper, 3.1wt% lead, 2.95wt% manganese, 0.36wt% nickel, 0.35wt% tin, 0.08wt% aluminum, 1.25wt% iron and the balance zinc.

[0112] S2. According to the component ratio, first place the copper in the melting furnace and heat it to 1150℃ to completely melt it. Then add the remaining components in sequence and stir continuously for 10 minutes to ensure that the components are mixed evenly to form a copper alloy melt.

[0113] S3. The copper alloy melt from step S2 is continuously cast into copper rods using a horizontal continuous casting equipment. The diameter of the copper rods is controlled to be 19 mm and the cooling rate is 330℃ / s to obtain copper rods with uniform structure. Then, the copper rods are stirred evenly with natural flake graphite (flake size 0.18 mm, fixed carbon content ≥95wt%) to make the surface roughness of the copper rods reach 0.8 μm.

[0114] S4. Heat the copper rod from step S3 to the hot forging temperature, which is controlled at 785℃. Forge for 3 seconds to form a copper part. Then, place the copper part into a heating device and heat it at 505℃ for 2 hours. After heat treatment, the copper part is shot peened to achieve a surface roughness of 3.6μm. Then, it is machined to produce the required shapes and sizes of various parts and assembled to obtain the refrigerant valve.

[0115] Example 14

[0116] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 13, except that in step S1, copper alloy raw materials are weighed according to the proportions, wherein the copper alloy raw materials include 50.9 wt% copper, 2.78 wt% lead, 2.99 wt% manganese, 0.45 wt% nickel, 0.55 wt% tin, 0.05 wt% aluminum, 0.85 wt% iron and the balance zinc.

[0117] Example 15

[0118] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 13, except that in step S3, the copper alloy melt from step S2 is continuously cast into a copper rod through a horizontal continuous casting equipment, the diameter of the copper rod is controlled to be 22 mm, and the cooling rate is 317 °C / s, so as to obtain a copper rod with uniform structure. Then the copper rod is stirred evenly with natural flake graphite (flake size 0.18 mm, fixed carbon content ≥95 wt%), so that the surface roughness of the copper rod reaches 1.0 μm.

[0119] Example 16

[0120] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 13, except that in step S4, the copper rod in step S3 is heated to the hot forging temperature, which is controlled at 780°C, and forged for 2 seconds to form a copper part. Then, the copper part is placed in a heating device and heated at 515°C for 2 hours. The heated copper part is then shot-peened to achieve a surface roughness of 3.3 μm. Finally, it is machined to produce the required shapes and sizes of various components, which are then assembled to obtain the refrigerant valve.

[0121] Example 17

[0122] A method for manufacturing a refrigerant valve includes the following steps:

[0123] S1. Weigh the copper alloy raw materials according to the proportions, wherein the copper alloy raw materials include 49.8wt% copper, 3.23wt% lead, 2.98wt% manganese, 0.37wt% nickel, 0.33wt% tin, 0.07wt% aluminum, 1.38wt% iron and the balance zinc.

[0124] S2. According to the component ratio, first place the copper in the melting furnace and heat it to 1000℃ to completely melt it. Then add the remaining components in sequence and stir continuously for 10 minutes to ensure that the components are mixed evenly to form a copper alloy melt.

[0125] S3. The copper alloy melt from step S2 is continuously cast into copper rods using a horizontal continuous casting equipment. The diameter of the copper rods is controlled to be 25 mm and the cooling rate is 325 °C / s to obtain copper rods with uniform structure. Then, the copper rods are stirred evenly with natural flake graphite (flake size 0.18 mm, fixed carbon content ≥95 wt%) to make the surface roughness of the copper rods reach 0.5 μm.

[0126] S4. Heat the copper rod from step S3 to the hot forging temperature, which is controlled at 790℃. Forge for 3 seconds to form a copper part. Then, place the copper part into a heating device and heat it at 530℃ for 2 hours. After heat treatment, the copper part is shot peened to achieve a surface roughness of 4.0μm. Then, it is machined to produce the required shapes and sizes of various parts and assembled to obtain the refrigerant valve.

[0127] Example 18

[0128] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 17, except that in step S1, copper alloy raw materials are weighed according to the proportions, wherein the copper alloy raw materials include 48.9 wt% copper, 2.75 wt% lead, 3.1 wt% manganese, 0.44 wt% nickel, 0.4 wt% tin, 0.09 wt% aluminum, 1.15 wt% iron and the balance zinc.

[0129] Example 19

[0130] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 17, except that in step S3, the copper alloy melt from step S2 is continuously cast into a copper rod using a horizontal continuous casting equipment, the diameter of the copper rod is controlled to be 35 mm, and the cooling rate is 345 °C / s, so as to obtain a copper rod with uniform structure. Then the copper rod is stirred evenly with natural flake graphite (flake size 0.18 mm, fixed carbon content ≥95 wt%), so that the surface roughness of the copper rod reaches 1.5 μm.

[0131] Example 20

[0132] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 17, except that in step S4, the copper rod in step S3 is heated to the hot forging temperature, which is controlled at 795°C, and forged for 2 seconds to form a copper part. Then, the copper part is placed in a heating device and heated at 535°C for 2 hours. The heated copper part is then shot-peened to achieve a surface roughness of 3.8 μm. Finally, it is machined to produce the required shapes and sizes of various components, which are then assembled to obtain the refrigerant valve.

[0133] Example 21

[0134] A method for manufacturing a refrigerant valve includes the following steps:

[0135] S1. Weigh the copper alloy raw materials according to the proportions, wherein the copper alloy raw materials include 49.8wt% copper, 3.46wt% lead, 3.05wt% manganese, 0.49wt% nickel, 0.38wt% tin, 0.1wt% aluminum, 0.001wt% boron and the balance zinc.

[0136] S2. According to the component ratio, first place the copper in the melting furnace and heat it to 1105℃ to completely melt it. Then add the remaining components in sequence and stir continuously for 10 minutes to ensure that the components are mixed evenly to form a copper alloy melt.

[0137] S3. The copper alloy melt from step S2 is continuously cast into copper rods using a horizontal continuous casting equipment. The diameter of the copper rods is controlled to be 15 mm and the cooling rate is 305 °C / s to obtain copper rods with uniform structure. Then, the copper rods are stirred evenly with natural flake graphite (flake size 0.18 mm, fixed carbon content ≥95 wt%) to make the surface roughness of the copper rods reach 1.2 μm.

[0138] S4. Heat the copper rod from step S3 to the hot forging temperature, which is controlled at 773℃. Forge for 4 seconds to form a copper part. Then, place the copper part into a heating device and heat it at 510℃ for 2 hours. After heat treatment, the copper part is shot peened to achieve a surface roughness of 2.5μm. Then, it is machined to produce the required shapes and sizes of various parts and assembled to obtain the refrigerant valve.

[0139] Example 22

[0140] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 21, except that in step S1, copper alloy raw materials are weighed according to the proportions, wherein the copper alloy raw materials include 50wt% copper, 3.2wt% lead, 1.85wt% manganese, 0.35wt% nickel, 0.35wt% tin, 0.1wt% aluminum, 0.005wt% boron and the balance zinc.

[0141] Example 23

[0142] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 21, except that in step S3, the copper alloy melt from step S2 is continuously cast into a copper rod using a horizontal continuous casting equipment, the diameter of the copper rod is controlled to be 20 mm, and the cooling rate is 300 °C / s, so as to obtain a copper rod with uniform structure. Then the copper rod is stirred evenly with natural flake graphite (flake size 0.18 mm, fixed carbon content ≥95 wt%) so that the surface roughness of the copper rod reaches 0.5 μm.

[0143] Example 24

[0144] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 21, except that in step S4, the copper rod in step S3 is heated to the hot forging temperature, which is controlled at 750°C, and forged for 3 seconds to form a copper part. Then, the copper part is placed in a heating device and heated at 540°C for 3 hours. The heated copper part is then shot-peened to achieve a surface roughness of 2.8 μm. Finally, it is machined to produce the required shapes and sizes of various components, which are then assembled to obtain the refrigerant valve.

[0145] Example 25

[0146] A method for manufacturing a refrigerant valve includes the following steps:

[0147] S1. Weigh the copper alloy raw materials according to the proportions, wherein the copper alloy raw materials include 52wt% copper, 3.56wt% lead, 2.95wt% manganese, 0.39wt% nickel, 0.35wt% tin, 0.07wt% aluminum, 0.47wt% iron and the balance zinc.

[0148] S2. According to the component ratio, first place the copper in the melting furnace and heat it to 1100℃ to completely melt it. Then add the remaining components in sequence and stir continuously for 10 minutes to ensure that the components are mixed evenly to form a copper alloy melt.

[0149] S3. The copper alloy melt from step S2 is continuously cast into copper rods using a horizontal continuous casting equipment. The diameter of the copper rods is controlled to be 24 mm and the cooling rate is 332℃ / s to obtain copper rods with uniform structure. Then, the copper rods are stirred evenly with natural flake graphite (flake size 0.18 mm, fixed carbon content ≥95wt%) to make the surface roughness of the copper rods reach 1.5 μm.

[0150] S4. Heat the copper rod from step S3 to the hot forging temperature, which is controlled at 768℃. Forge for 1 second to form a copper part. Then, place the copper part into a heating device and heat it at 600℃ for 1 hour. After heat treatment, the copper part is shot peened to achieve a surface roughness of 2.1μm. Then, it is machined to produce the required shape and size of each component and assembled to obtain the refrigerant valve.

[0151] Example 26

[0152] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 25, except that in step S1, copper alloy raw materials are weighed according to the proportions, wherein the copper alloy raw materials include 51.4 wt% copper, 3.56 wt% lead, 2.95 wt% manganese, 0.32 wt% nickel, 0.38 wt% tin, 0.07 wt% aluminum, 0.47 wt% iron and the balance zinc.

[0153] Example 27

[0154] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 25, except that in step S3, the copper alloy melt from step S2 is continuously cast into a copper rod using a horizontal continuous casting equipment, the diameter of the copper rod is controlled to be 24 mm, and the cooling rate is 316 °C / s, so as to obtain a copper rod with uniform structure. Then the copper rod is stirred evenly with natural flake graphite (flake size 0.18 mm, fixed carbon content ≥95 wt%), so that the surface roughness of the copper rod reaches 1.5 μm.

[0155] Example 28

[0156] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 25, except that in step S4, the copper rod in step S3 is heated to the hot forging temperature, which is controlled at 780°C, and forged for 1 second to form a copper part. Then, the copper part is placed in a heating device and heated at 550°C for 2 hours. The heated copper part is shot peened to achieve a surface roughness of 2.1 μm. Then, it is machined to produce the required shape and size of each component, and assembled to obtain the refrigerant valve.

[0157] Example 29

[0158] A method for manufacturing a refrigerant valve includes the following steps:

[0159] S1. Weigh the copper alloy raw materials according to the proportions, wherein the copper alloy raw materials include 52.1wt% copper, 3.3wt% lead, 3.0wt% manganese, 0.72wt% nickel, 0.4wt% tin, 0.25wt% aluminum and the balance zinc;

[0160] S2. According to the component ratio, first place the copper in the melting furnace and heat it to 1200℃ to completely melt it. Then add the remaining components in sequence and stir continuously for 5 minutes to ensure that the components are mixed evenly to form a copper alloy melt.

[0161] S3. The copper alloy melt from step S2 is continuously cast into copper rods using a horizontal continuous casting equipment. The diameter of the copper rods is controlled to be 24 mm and the cooling rate is 350℃ / s to obtain copper rods with uniform structure. Then, the copper rods are stirred evenly with natural flake graphite (flake size 0.18 mm, fixed carbon content ≥95wt%) to make the surface roughness of the copper rods reach 1.8 μm.

[0162] S4. Heat the copper rod from step S3 to the hot forging temperature, which is controlled at 782℃. Forge for 3 seconds to form a copper part. Then, place the copper part into a heating device and heat it at 525℃ for 2 hours. After heat treatment, the copper part is shot peened to achieve a surface roughness of 3.0μm. Then, it is machined to produce the required shapes and sizes of various parts and assembled to obtain the refrigerant valve.

[0163] Example 30

[0164] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 29, except that in step S1, copper alloy raw materials are weighed according to the proportion, wherein the copper alloy raw materials include 51.8 wt% copper, 3.3 wt% lead, 4.5 wt% manganese, 0.94 wt% nickel, 0.3 wt% tin, 0.25 wt% aluminum and the balance zinc.

[0165] Example 31

[0166] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 29, except that in step S3, the copper alloy melt from step S2 is continuously cast into a copper rod using a horizontal continuous casting equipment, the diameter of the copper rod is controlled to be 27 mm, and the cooling rate is 342 °C / s, so as to obtain a copper rod with uniform structure. Then the copper rod is stirred evenly with natural flake graphite (flake size 0.18 mm, fixed carbon content ≥95 wt%), so that the surface roughness of the copper rod reaches 1.7 μm.

[0167] Example 32

[0168] A method for manufacturing a refrigerant valve, wherein all other steps are the same as in Example 29, except that in step S4, the copper rod in step S3 is heated to the hot forging temperature, which is controlled at 761°C, and forged for 3 seconds to form a copper part. Then, the copper part is placed in a heating device and heated at 575°C for 2 hours. The heated copper part is then shot-peened to achieve a surface roughness of 2.5 μm. Finally, it is machined to produce the required shapes and sizes of various components, which are then assembled to obtain the refrigerant valve.

[0169] Test methods

[0170] 1. The tensile strength and elongation at break of the cut copper alloy refrigerant valve specimens shall be tested in accordance with GB / T 228-1-2021 "Metallic materials - Tensile testing - Part 1: Room temperature test method"; the hardness of the specimens shall be tested in accordance with GB / T 4340.1-2024 "Metallic materials - Vickers hardness test - Part 1: Test method".

[0171] 2. The standards and methods for the ammonia fumigation cracking test are as follows:

[0172] (a) A valve body 11, a first valve cap 13, a second valve cap 2 and a connecting nut 14 were made from the copper alloy of the examples and comparative examples. The first valve cap 13 and the second valve cap 2 were sealed to the valve body 11 with a torque of 40 N·m, and the connecting nut 14 was sealed to the valve body 11 with a torque of 39 N·m to make a sample piece.

[0173] (b) Prepare a 28wt% ammonia solution and pour it into the container along the container wall. The container must be sealed and not vibrated to prevent ammonia evaporation. Do not put in any items that may affect the ammonia solution. Take four sets of valve bodies 11 assembled in step (a) and seal the other openings of valve bodies 11 with tape to prevent the ammonia solution from entering the inner cavity of valve bodies 11. Then place valve bodies 11 above the ammonia solution, ensuring that valve bodies 11 do not contact the ammonia solution. Place them at 25°C for 72 hours. The test environment for the ammonia fumigation corrosion test is a closed environment with a container volume of 101L. Test the ammonia fumigation stress corrosion resistance of the specimen. The requirement for the use of the gate valve is that the surface of the specimen must not have any fine cracks, and there must be no cracks or fissures that may affect the performance.

[0174] 3. Air tightness test: The air tightness of the refrigerant valve is tested by external water leakage test. Taking the shut-off valve as an example, the valve body 11, first valve cap 13, and second valve cap 2 of the shut-off valve are made of copper alloy as described in Examples 12-19. The valve stem is closed with a sealing torque of 39 N·m. All nuts are loosened and the remaining pipe ports are sealed. Dry air is introduced into the inlet pipe of the shut-off valve to 4 MPa. The valve is then immersed in a water tank for 3 minutes. No air bubbles should be generated to determine the shut-off valve's air tightness. The sample is then dried after the test.

[0175] In accordance with the test method for the cutting performance of copper-zinc-bismuth-tellurium alloy rods in YS / T 647-2007, a refrigerant valve made of copper alloy material was used as a sample for testing. The evaluation criteria for "excellent", "good", "average" and "poor" in the cutting performance were as follows.

[0176]

[0177] A copper alloy refrigerant valve was cut into sections and used as a sample for testing. The evaluation criteria for "excellent", "good", "relatively good" and "poor" in the hot forging performance of the refrigerant valve were determined using a gate valve hot forging equipment, as shown below.

[0178]

[0179] The evaluation criteria for "Excellent", "Good", "Fairly Good", and "Poor" in the ammonia fumigation corrosion resistance test, obtained according to the test method in "2. Standards and Methods for Ammonia Fumigation Cracking Test" above, are as follows.

[0180]

[0181] The hardness, tensile strength, and elongation at break of the copper alloy material of the refrigerant valves in Examples 1-32 were tested, as were the resistance to ammonia corrosion and the airtightness of the refrigerant valves. The test results are shown in Table 1.

[0182] Table 1 shows the test results of various performance parameters of the refrigerant valves in Examples 1-32.

[0183]

[0184]

[0185]

[0186] As shown in Table 1, the copper alloy materials of the refrigerant valves in Examples 1-32 all have good tensile strength and hardness, as well as high elongation at break. This means that the refrigerant valves maintain good plasticity while ensuring high mechanical properties. In addition, Examples 1-32 also have excellent resistance to ammonia fuming stress corrosion and refrigerant impact. This indicates that the present application uses a suitable manufacturing process combined with specific alloy components, and the elements have a certain synergistic effect under specific process conditions, which improves the plasticity of the copper alloy. This makes the copper alloy refrigerant valve less prone to stress corrosion cracking in high-pressure or ammonia environments, while also having high tensile strength and hardness, as well as excellent resistance to stress corrosion, resistance to refrigerant thermal shock, plasticity, and airtightness. As a result, the refrigerant valve has excellent comprehensive performance.

[0187] As can be seen from Table 1, compared with Examples 1, 5, 9, 13, 17, 21, 25 and 29, the elongation at break of the refrigerant valves in Examples 13, 17, 21, 25 and 29 are all higher than those in Examples 1, 5 and 9, and their resistance to ammonia corrosion is also better than that in Examples 1, 5 and 9. This indicates that when the tin content in the copper alloy is 0.25wt%-0.4wt%, or the nickel content is 0.35wt%-0.8wt%, under specific manufacturing process conditions, the copper alloy has higher strength and hardness, as well as better ductility, plasticity and resistance to thermal shock, and better resistance to ammonia corrosion. It is less prone to stress corrosion cracking, giving the refrigerant valve better comprehensive performance and meeting the requirements for use in harsh environments (such as high temperature and high pressure). Therefore, selecting appropriate proportions of each element and using them in combination with the manufacturing process conditions of this application can improve the comprehensive performance of the copper alloy, thereby increasing the service life of the refrigerant valve.

[0188] Partial valve body samples (at the same location) of the refrigerant valves in Examples 1, 21 and 25 were cut and tested. Electron backscatter diffraction (EBSD) and XRD were used to detect the phase composition of partial valve body samples (at the same location) in Examples 1, 21 and 25. Three locations were randomly selected for each sample for testing, and the average value was taken. The test results are shown in Table 2.

[0189] Table 2. Phase composition analysis of Examples 1, 21, and 25.

[0190]

[0191] As can be seen from Table 2, the phase composition of the valve body in Examples 1, 21, and 25 includes a β phase and free lead particles. Figure 6 , Figure 7 and Figure 8The images show the metallographic morphology of Examples 1, 21, and 25, respectively. EBSD and XRD analysis revealed that the β phase area of ​​the valve body in Examples 1, 21, and 25 was greater than 90%, while the lead particles accounted for 1-3%. In this application, the β phase is the main matrix phase, containing a small amount of lead particles. Lead is distributed in a free state within the grains and grain boundaries of the copper alloy, giving the copper alloy good machinability and wear resistance. This, in turn, improves the stress corrosion resistance, impact resistance, and mechanical properties of the refrigerant valve, allowing it to maintain a long service life even under the impact of high temperature and high pressure refrigerant. Specifically, Example 21... Compared with Example 25, where the β phase area ratio was 95-96% and the lead particle area ratio was 1.5-2% obtained from EBSD analysis, the elongation at break and resistance to ammonia corrosion in Examples 21 and 25 were better than those in Example 1. This indicates that the present application uses a suitable manufacturing process combined with specific alloy components, and the elements have a certain synergistic effect under specific process conditions, thereby obtaining a phase composition with β phase as the main matrix phase and containing a small amount of lead particles. This makes the refrigerant valve have better plasticity or toughness and stress corrosion resistance, can withstand the strong impact of refrigerant, improve the service life of the refrigerant valve, and is not prone to leakage, with excellent airtightness.

Claims

1. A refrigerant valve, the refrigerant valve comprising a stationary part (1) and a movable part (7), the movable part (7) being at least partially located within the stationary part (1), the movable part (7) being movable relative to the stationary part (1) to control the connection between different valve ports or the regulation of refrigerant flow, characterized in that, The stationary part (1) has an inner cavity (114) which can be used to circulate refrigerant. At least one of the stationary part (1) and the moving part (7) is made of an alloy material. The alloy material comprises a β phase and free lead particles, wherein the area of ​​the β phase is greater than 90%.

2. The refrigerant valve according to claim 1, characterized in that, The area ratio of the β phase is 91-99%.

3. The refrigerant valve according to claim 1 or 2, characterized in that, The area ratio of the lead particles is 1-3%.

4. The refrigerant valve according to claim 1 or 2, characterized in that, The alloy material is a copper alloy, and the average grain size of the copper alloy is 50-250 μm.

5. The refrigerant valve according to claim 1 or 2, characterized in that, The stationary part (1) includes a valve body (11), the valve body (11) is made of the alloy material, the valve body (11) has a first cavity (111), and the inner cavity (114) includes the first cavity (111); The moving part (7) includes a valve stem, which is at least partially located in the first chamber (111). The refrigerant valve includes at least two valve ports and a drive part capable of driving the valve stem to move to control the on / off state between the at least two valve ports.

6. The refrigerant valve according to claim 1 or 2, characterized in that, The stationary part (1) includes a valve body (11), the valve body (11) is made of the alloy material, the valve body (11) has a first cavity (111), and the inner cavity (114) includes the first cavity (111); The moving part (7) includes a valve core (102) at least partially located in the first chamber (111), the valve core (102) having a second chamber (103), and the refrigerant valve includes a drive part capable of driving the valve core (102) to rotate to control the opening and closing between the first chamber (111) and the second chamber (103).

7. The refrigerant valve according to claim 1 or 2, characterized in that, The stationary part (1) includes a valve body (11), the moving part (7) includes a valve stem, and the refrigerant valve includes a first connecting pipe (5), a second connecting pipe (4), a valve cap (13, 2), and a connecting nut (14). The first connecting pipe (5) is fixedly connected to the valve body (1) or integrally formed, and the second connecting pipe (4) is fixedly connected to the valve body (11) or integrally formed. The first connecting pipe (5) has a first channel (110), and the second connecting pipe (4) has a second channel (120). The valve stem can control the fluid isolation or fluid communication between the first channel (110) and the second channel (120). The valve cap (13, 2) and the connecting nut (14) are both connected to the valve body (11).

8. The refrigerant valve according to claim 1 or 2, characterized in that, After the refrigerant valve undergoes an ammonia corrosion resistance test, the stationary part (1) includes a valve body (11), the valve body (11) is made of the alloy material, and at least a portion of the surface of the valve body (11) is free from cracks that affect sealing performance. The test conditions for the ammonia corrosion resistance test are as follows: (a) Apply at least one torque of 30-40 N·m to the valve body (11); (b) Prepare an ammonia solution with a concentration of 20-30wt% and place it in a container. Place the valve body (11) from step (a) above the ammonia solution, ensuring that the valve body (11) does not contact the ammonia solution. Place the container at 20℃-30℃ for 72 hours. The test environment for the ammonia corrosion resistance test is a closed environment, and the volume of the container is 90-105L.

9. The refrigerant valve according to claim 1 or 2, characterized in that, The alloy material comprises 0.11wt%-0.9wt% tin, 48wt%-55wt% copper, 1.5wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.3wt%-2.0wt% nickel and 35wt%-44wt% zinc.

10. The refrigerant valve according to claim 1 or 2, characterized in that, The alloy material comprises 0.2wt%-0.4wt% tin, 48wt%-53wt% copper, 3.0wt%-4.0wt% lead, 2.5wt%-3.0wt% manganese, 0.3wt%-0.5wt% nickel and 40wt%-45wt% zinc.

11. The refrigerant valve according to claim 1 or 2, characterized in that, The alloy material comprises 0.1 wt% to 1.5 wt% iron, and / or, the alloy material comprises 0.001 wt% to 0.1 wt% boron.

12. The refrigerant valve according to claim 11, characterized in that, The alloy material comprises 0.1 wt% to 0.5 wt% iron, and / or, the alloy material further comprises 0.001 wt% to 0.05 wt% boron.

13. A method for manufacturing a refrigerant valve, the refrigerant valve comprising a stationary part (1) and a movable part (7), the movable part (7) being at least partially located within the stationary part (1), the movable part (7) being movable relative to the stationary part (1) to control the connection between different valve ports or the regulation of refrigerant flow, characterized in that, The stationary part (1) has an inner cavity (114) that can be used to circulate refrigerant. The method for manufacturing at least one of the stationary part (1) and the moving part (7) includes the following steps: Provide metal raw materials; The metal raw materials are placed in a furnace and smelted to form an alloy melt; The alloy melt is cast to form an alloy rod; The alloy rod is hot-forged and heat-treated. The heat-treated alloy comprises a β phase and free lead particles, wherein the area of ​​the β phase is ≥90%. The alloy comprises 0.11wt%-0.9wt% tin, 48wt%-55wt% copper, 1.5wt%-4.0wt% lead, 1.5wt%-4.5wt% manganese, 0.3wt%-2.0wt% nickel and 35wt%-44wt% zinc; The heat treatment temperature is 450℃-600℃, and the heat treatment time is 1-3h.

14. The manufacturing method according to claim 13, characterized in that, The hot forging temperature is 750℃-800℃, and the hot forging time is 1-5s.

15. The manufacturing method according to claim 13 or 14, characterized in that, After the alloy melt is cast, a cooling step is also included, and the cooling rate is 300℃ / s-350℃ / s.

16. The manufacturing method according to claim 13 or 14, characterized in that, The steps prior to hot forging the alloy rod further include: cutting the alloy rod into appropriate sizes, then adding graphite and stirring the copper rod evenly to obtain an alloy rod with a surface roughness of 0.5-2.0 μm.

17. The manufacturing method according to claim 13 or 14, characterized in that, The alloy material comprises 0.2wt%-0.4wt% tin, 48wt%-52wt% copper, 3.0wt%-4.0wt% lead, 2.5wt%-3.0wt% manganese, 0.3wt%-0.5wt% nickel and 40wt%-45wt% zinc.

18. The manufacturing method according to claim 13 or 14, characterized in that, The alloy material further includes 0.1wt%-1.5wt% iron, and / or, the alloy material further includes 0.001wt%-0.1wt% boron.

19. The manufacturing method according to claim 13 or 14, characterized in that, The alloy material further includes 0.1wt%-0.5wt% iron, and / or, the alloy material further includes 0.001wt%-0.05wt% boron.

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