Manufacturing method of high-strength and high-wear-resistance CuNiSnMn alloy plate

Abstract

The invention provides a manufacturing method of a high-strength and high-wear-resistance CuNiSnMn series alloy plate, which belongs to the technical field of high-performance copper alloys, and has the technical key points that electrolytic Cu, Ni, Sn and Mn are put into a vacuum melting furnace, a cast ingot of the material is obtained through the steps of melting, refining, casting forming and the like, and the cast ingot is processed into a plate product with the required specification through multiple times of rolling and heat treatment. By means of the process, it can be ensured that the strength of the high-strength and high-wear-resistance CuNiSnMn series alloy plate is not changed in the high-temperature environment of 470 DEG C or below for a long time, and in other words, the higher over-aging resistance is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of high-performance copper alloys, and is specifically a method for manufacturing high-strength and high-wear-resistant CuNiSnMn alloy plates. The process of the present invention is mainly used to produce bearings, sleeves, bushings and other parts under high load, high speed, high temperature and other environments. Background Art

[0002] CuNiSnMn alloy is a high-strength and high-elastic alloy with the advantages of high strength, high hardness, corrosion resistance, small deformation after aging, non-toxic and environmentally friendly, and low friction coefficient and low wear rate. It is widely used in bearings, sleeves, bushings and other parts under high load and high speed environments. However, if CuNiSnMn alloy is exposed to an environment above 350℃ for a long time, serious discontinuous precipitation will occur, resulting in performance degradation.

[0003] The process of the present invention ensures that the strength of the CuNiSnMn alloy remains unchanged in a high temperature environment below 470° C. for a long time through vacuum melting, cold rolling, solid solution and aging treatment, that is, it has stronger anti-aging performance. Summary of the invention

[0004] The purpose of the present invention is to provide a method for manufacturing a high-strength and high-wear-resistant CuNiSnMn alloy plate. The prepared alloy plate can be used for parts such as bearings, sleeves and bushings under high load, high speed and high temperature environments.

[0005] The object of the present invention is achieved through the following technical solution: A method for manufacturing a high-strength and high-wear-resistant CuNiSnMn alloy plate, comprising a material casting step and a processing step, characterized in that: The alloy plate comprises the following components in percentage by mass: Ni: 11.0-13.0%, Sn: 7.0-9.0%, Mn: 8.0-12.0%, and the balance is Cu; The material casting steps include: taking electrolytic Cu, electrolytic Ni, metal Mn and metal Sn as raw materials in proportion, loading them into a crucible, sealing the furnace and evacuating the furnace to a vacuum degree of 0-20 Pa; supplying power to the vacuum induction melting furnace to melt the raw materials at a melting temperature of 1250-1350° C.; after the melting is complete, controlling the furnace temperature at 1150-1200° C., and refining for 20-30 minutes; after the refining is completed, filling the furnace with argon gas until the vacuum degree reaches 0.06-0.09 MPa, tilting the furnace 2-3 times, casting with electricity, cooling for 15-30 minutes, and taking out the ingot after a crust forms on the surface of the molten metal; The processing steps include: performing homogenization treatment on the ingot after milling, and cooling in water after heat preservation; performing cold rolling to open the ingot after milling, with a processing rate of 40-60%; performing solid solution treatment after cold rolling; performing multiple cold rolling and solid solution treatments, and rolling the finished product with a thickness of 3.0-5.0 mm; the cold rolling processing rate between each solid solution treatment is 40-60%; performing vacuum aging treatment on the finished product, and furnace cooling after heat preservation.

[0006] Furthermore: the homogenization treatment temperature is 700-840°C, and the insulation time is 3-10h.

[0007] Furthermore: the solution treatment temperature is 700-840°C, and the holding time is 0.5-3h.

[0008] Furthermore: the aging treatment temperature is 400-500°C, and the insulation time is 3-6h.

[0009] The high-strength and high-wear-resistant CuNiSnMn alloy plate prepared by the present invention is composed of four elements. Generally, the casting structure of the CuNiSnMn alloy has serious microscopic and macroscopic component segregation. When the Mn content is 8-12%, microcracks are easily generated in the dendrite gaps, affecting subsequent product processing. The present invention reduces component segregation through vacuum smelting, and dissolves the brittle bone-like substances in the structure into the matrix through homogenization treatment, thereby forming a single-phase solid solution, which is convenient for subsequent cold rolling and greatly improves the processing performance and yield. Utilize a suitable solution treatment and vacuum aging treatment system to ensure that the alloy precipitates MnNi in the matrix. 2 Sn phase, which can effectively inhibit grain growth and prevent the performance of the alloy from decreasing in high temperature environments. 2 The Sn phase has a BCC structure, which can greatly improve the strength and wear resistance of the material.

[0010] The present invention has the following advantages: Compared with the existing CuNiSnMn alloy process, the present invention adopts a combination of vacuum melting and homogenization treatment, which greatly improves the segregation defects in the ingot structure, reduces the production difficulty, and effectively improves the product qualification rate. At the same time, it also improves the mechanical properties, wear resistance and high temperature resistance of the alloy plate, ensuring the stability of the performance of the alloy of the present invention at higher ambient temperatures. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a SEM image of the alloy of Example 4 during aging treatment; Figure 2 This is the SEM image of the comparative alloy during aging treatment. DETAILED DESCRIPTION

[0012] The present invention will be further described in detail below through specific examples, but the following examples are only used to more clearly illustrate the technical solutions of the present invention and cannot limit the scope of protection of the present invention.

[0013] Example 1: Electrolytic Cu, electrolytic Ni, metallic Mn and metallic Sn are used as raw materials, and the masses of the components are: 108 kg electrolytic Cu, 18 kg electrolytic Ni, 12 kg metallic Mn and 12 kg metallic Sn, with a total weight of 150 kg.

[0014] The raw materials were loaded into the crucible, the furnace was sealed and evacuated, and the vacuum degree was 12 Pa. The vacuum furnace induction melting furnace was powered on to melt the raw materials, and the melting temperature was 1310°C. After the melting was complete, the furnace temperature was controlled at 1190°C and the refining was performed for 25 minutes. After the refining was completed, argon was filled into the furnace until the vacuum degree reached 0.09MPa, the furnace was tilted 3 times, and the casting was performed with electricity. After cooling for 20 minutes, the ingot was taken out after the surface of the molten metal was crusted, and the thickness of the ingot was 40mm; The ingot was milled and homogenized at 840℃ for 8h. After the insulation, it was put into water. After grinding, the ingot is cold rolled to form a blank with a processing rate of 50%. After cold rolling to 20 mm, it is solution treated at a temperature of 840°C for 1 hour. After the insulation, it is put into water; After grinding, the slab is cold-rolled to 10 mm and subjected to solution treatment at 840 ° C for 1 h. After the insulation, it is put into water. After grinding, the slab is cold-rolled to a finished product size of 5 mm. The finished plate is loaded into a vacuum annealing furnace, with a heating temperature of 410°C and a holding time of 6 hours. After the holding time is completed, the furnace is cooled.

[0015] Example 2: Electrolytic Cu, electrolytic Ni, metallic Mn and metallic Sn are used as raw materials, and the masses of the components are: 108 kg electrolytic Cu, 16.5 kg electrolytic Ni, 12 kg metallic Mn, 13.5 kg metallic Sn, with a total weight of 150 kg.

[0016] The raw materials were loaded into the crucible, the furnace was sealed and evacuated, and the vacuum degree was 12Pa. The vacuum furnace induction melting furnace was powered on to melt the raw materials, and the melting temperature was 1280℃. After the melting was complete, the furnace temperature was controlled at 1160℃, and the refining was carried out for 20 minutes. After the refining was completed, argon was filled into the furnace until the vacuum degree reached 0.08MPa, the furnace was tilted twice, and the casting was carried out with electricity, and the ingot was taken out after the surface of the molten metal was crusted. The thickness of the ingot was 40mm; The ingot is milled and homogenized at 800℃ for 9h. After the insulation, it is put into water. After grinding, the ingot is cold rolled to form a blank with a processing rate of 40%. After cold rolling to 24 mm, it is solution treated at a temperature of 800°C for 2 hours and then put into water after the insulation is completed. After grinding, the slab is cold rolled to 14mm, and then solution treated at 800℃ for 1.5h. After the insulation, it is put into water. After grinding, the slab is cold rolled to 8mm, and then solution treated at 800℃ for 1h. After the insulation, it is put into water. After grinding, the slab is cold rolled to the finished product size of 4mm. The finished plates are placed into a vacuum annealing furnace with a heating temperature of 460°C and a holding time of 5 hours. The furnace is cooled after the holding period.

[0017] Example 3: Electrolytic Cu, electrolytic Ni, metallic Mn and metallic Sn are used as raw materials, and the masses of the components are: 102 kg electrolytic Cu, 18 kg electrolytic Ni, 18 kg metallic Mn, 12 kg metallic Sn, with a total weight of 150 kg.

[0018] The raw materials were loaded into the crucible, the furnace was sealed and evacuated, and the vacuum degree was 12 Pa. The vacuum furnace induction melting furnace was powered on to melt the raw materials, and the melting temperature was 1310°C. After the melting was complete, the furnace temperature was controlled at 1190°C and the refining was performed for 25 minutes. After the refining was completed, argon was filled into the furnace until the vacuum degree reached 0.09MPa, the furnace was tilted 3 times, and the casting was performed with electricity. After cooling for 20 minutes, the ingot was taken out after the surface of the molten metal was crusted, and the thickness of the ingot was 40mm; The ingot is milled and homogenized at 720℃ for 10h. After the insulation, it is put into water. After grinding, the ingot is cold rolled to form a blank with a processing rate of 50%. After cold rolling to 20 mm, it is solution treated at a temperature of 840°C for 1 hour. After the insulation, it is put into water; After grinding, the slab is cold rolled to 10mm and then subjected to solution treatment at 840℃ for 1h. After the insulation, the slab is put into water. After grinding, the slab is cold rolled to the finished product size of 5mm. The finished plates are placed in a vacuum annealing furnace with a heating temperature of 410°C and a holding time of 6 hours. The furnace is cooled after the holding period.

[0019] Example 4: Electrolytic Cu, electrolytic Ni, metallic Mn and metallic Sn are used as raw materials, and the masses of the components are: 102 kg electrolytic Cu, 19.5 kg electrolytic Ni, 18 kg metallic Mn, 10.5 kg metallic Sn, with a total weight of 150 kg.

[0020] The raw materials were loaded into the crucible, the furnace was sealed and evacuated, and the vacuum degree was 12Pa. The vacuum furnace induction melting furnace was powered on to melt the raw materials, and the melting temperature was 1280℃. After the melting was complete, the furnace temperature was controlled at 1160℃, and the refining was carried out for 20 minutes. After the refining was completed, argon was filled into the furnace until the vacuum degree reached 0.08MPa, the furnace was tilted twice, and the casting was carried out with electricity, and the ingot was taken out after the surface of the molten metal was crusted. The thickness of the ingot was 40mm; The ingot was milled and homogenized at 740℃ for 9h. After the insulation, it was put into water. After grinding, the ingot is cold rolled to form a blank with a processing rate of 40%. After cold rolling to 24 mm, it is solution treated at a temperature of 820°C for 2 hours. After the insulation, it is put into water; After grinding, the slab is cold rolled to 14mm, and then solution treated at 820℃ for 1.5h. After the insulation, it is put into water. After grinding, the slab is cold rolled to 7mm, and then solution treated at 820℃ for 1h. After the insulation, it is put into water. After grinding, the slab is cold rolled to the finished product size of 3mm. The finished plates are placed into a vacuum annealing furnace, heated to 440°C, and held for 5 hours. The furnace is cooled after the holding period.

[0021] Comparative Example: A Cu-12Ni-8Sn-8Mn alloy prepared by conventional production method was selected as a comparative example. The alloy contains 12% Ni, 8% Sn and 8% Mn, and the balance is Cu.

[0022] The comparative examples and the products of the above embodiments were selected for testing, and the specific description is as follows.

[0023] The performance of the finished alloy plate of the embodiment and the alloy plate of the comparative example were compared. As shown in Table 1, the material of the present invention is superior to the traditional CuNiSnMn alloy in terms of tensile strength, yield strength, Brinell hardness, friction and wear.

[0024] Table 1 Alloy performance comparison project Comparative Example Example 1 Example 2 Example 3 Example 4 Tensile strength / MPa 1128 1199 1195 1230 1209 Yield strength / MPa 1045 1071 1088 1114 1106 Brinell hardness HB 368 378 378 386 389 Friction and wear 0.000065g / s 0.000041g / s 0.000037g / s 0.000035g / s 0.000032g / s In the high temperature test, the performance of the example and comparative alloy plates was compared, as shown in Table 2-3. It can be found that when the temperature is higher than 400°C, the Brinell hardness of the comparative alloy plate reaches a peak value in 2-4 hours, and the hardness decreases rapidly with the increase of time; the example alloy can reach the hardness peak in 2-4 hours at 400-460°C, and the hardness remains basically unchanged after the time increases to 12 hours.

[0025] Table 2 Comparison of Brinell hardness of alloys at 400℃ time Comparative Example Example 1 Example 2 Example 3 Example 4 1h 242 215 220 208 204 2h 351 365 372 283 301 4h 365 374 367 386 388 8h 358 371 375 384 393 12h 333 378 377 383 389

[0026] Table 3 Comparison of Brinell hardness of alloys at 460℃ time Comparative Example Example 1 Example 2 Example 3 Example 4 1h 331 369 363 310 311 2h 343 372 376 357 362 4h 316 375 374 364 364 8h 287 375 378 361 365 12h 262 370 375 368 360

[0027] In summary, refer to the attached Figure 1-2During the aging process, the precipitated phase of the CuNiSnMn alloy can precipitate at the grain boundary or within the grain, and the morphology is lamellar structure. The precipitated phase within the grain continues to grow along a certain direction as the aging time increases and eventually cuts the original grain, achieving the purpose of grain refinement, while increasing the aging hardening effect, thereby improving the mechanical properties of the alloy. In addition, after a long period of aging treatment at a suitable temperature, the precipitated phase of the alloy will not grow infinitely until it fills the entire grain, as is the case with ordinary CuNiSnMn alloys, but will maintain a certain percentage and no longer increase, effectively inhibiting the grain boundary reaction and grain coarsening, and ensuring the thermal stability of the alloy at higher temperatures.

[0028] By comparing the performance of the alloy plates of the embodiment and the comparative example, it can be proved that the configuration structure can be transformed into a single phase without segregation by vacuum melting combined with homogenization treatment. By using subsequent reasonable solid solution treatment and vacuum aging treatment, the mechanical properties and friction and wear properties of the CuNiSnMn alloy are better than those of the CuNiSnMn alloy prepared by the traditional production method, and it can ensure that the strength remains unchanged in a high temperature environment below 470°C for a long time, that is, it has a stronger anti-aging performance.

[0029] Finally, it should be noted that the above specific implementation modes are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail, those skilled in the art should understand that the implementation modes of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the implementation modes of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for manufacturing a high-strength and high-wear-resistant CuNiSnMn alloy plate, comprising a material casting step and a processing step, characterized in that: The alloy plate comprises the following components in percentage by mass: Ni: 11.0-13.0%, Sn: 7.0-9.0%, Mn: 8.0-12.0%, and the balance is Cu; The material casting steps include: taking electrolytic Cu, electrolytic Ni, metal Mn and metal Sn as raw materials in proportion, loading them into a crucible, sealing the furnace and evacuating the furnace to a vacuum degree of 0-20 Pa; supplying power to the vacuum induction melting furnace to melt the raw materials at a melting temperature of 1250-1350° C.; after the melting is complete, controlling the furnace temperature at 1150-1200° C., and refining for 20-30 minutes; after the refining is completed, filling the furnace with argon gas until the vacuum degree reaches 0.06-0.09 MPa, tilting the furnace 2-3 times, casting with electricity, cooling for 15-30 minutes, and taking out the ingot after a crust forms on the surface of the molten metal; The processing steps include: performing homogenization treatment on the ingot after milling, and cooling in water after heat preservation; performing cold rolling to open the ingot after milling, with a processing rate of 40-60%; performing solid solution treatment after cold rolling; performing multiple cold rolling and solid solution treatments, and rolling the finished product with a thickness of 3.0-5.0 mm; the cold rolling processing rate between each solid solution treatment is 40-60%; performing vacuum aging treatment on the finished product, and furnace cooling after heat preservation.

2. The method for manufacturing a high-strength and high-wear-resistant CuNiSnMn alloy plate according to claim 1, characterized in that: The homogenization treatment temperature is 700-840° C., and the insulation time is 3-10 hours.

3. The method for manufacturing a high-strength and high-wear-resistant CuNiSnMn alloy plate according to claim 1, characterized in that: The solution treatment temperature is 700-840° C., and the holding time is 0.5-3 h.

4. The method for manufacturing a high-strength and high-wear-resistant CuNiSnMn alloy plate according to claim 1, characterized in that: The aging treatment temperature is 400-500° C., and the insulation time is 3-6 hours.

Images