Preparation method of alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-iron brake lining

Abstract

The invention relates to the field of friction materials, in particular to a preparation method of a high-temperature and high-strength copper alloy-based composite material for an alloy-reinforced high-iron brake pad. The high-temperature and high-strength copper alloy-based composite material for the high-iron brake lining is prepared by using a matrix alloy strengthening method, a high-temperature and high-strength Cu-Ni-Al alloy is strengthened by using an alloying element Si, and the Cu-Ni-Al-Si alloy is used as a matrix material; feCu30 is used as a matrix strengthening component; crFe and SiO2 are used as friction increasing components; graphite (flake) and MoS2 are used as anti-attrition components. The Cu-Ni-Al-Si alloy powder is prepared from the following raw materials in percentage by mass: 40 to 60 percent by weight of Cu-Ni-Al-Si alloy powder, 20 to 35 percent by weight of FeCu30 powder, 5 to 15 percent by weight of CrFe powder, 5 to 20 percent by weight of graphite powder, 0.5 to 5 percent by weight of MoS2 powder and 0.5 to 5 percent by weight of SiO2 powder. After the raw material powder is uniformly mixed, cold press molding is carried out, and hot pressed sintering is carried out under a vacuum condition. Compared with a commercial pure copper-based composite material and a Cu-Ni-Al-based composite material, the hardness and the strength of the high-temperature and high-strength Cu-Ni-Al-Si-based composite material are improved, and the friction coefficient stability and the wear resistance are remarkably improved.

Description

Technical Field

[0001] The present invention relates to the field of friction materials, in particular to a method for preparing an alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-speed railway brake pads, which is particularly suitable for high-speed train disc brake systems. Background Art

[0002] Copper-based composites, due to their excellent thermal conductivity, wear resistance, and stable friction coefficient, have become the primary material for brake pads in high-speed train disc brake systems. As high-speed trains continue to increase in speed, commercial brake pads made of pure copper-based composites are susceptible to softening during the braking process, which causes the composite's friction coefficient to decline, leading to increased wear and reduced train safety. Therefore, improving the material's friction coefficient stability and wear resistance at high speeds is a key issue that needs to be addressed in copper-based composites for high-speed rail brake pads.

[0003] At present, composite reinforcement is widely used at home and abroad to improve the performance of copper-based composite materials for brake pads. However, the weak interface bonding between the reinforcement particles and the Cu matrix makes it easy to fall off during high-speed braking, resulting in a significant decrease in braking stability. Alloy reinforcement can improve the mechanical properties of composite materials, while having little effect on the interfacial bonding strength between the matrix and the reinforcement, and can even enhance the interfacial bonding strength in some cases. However, strengthening with a single alloy element does not significantly improve the high-temperature strength and high-temperature tribological properties of the composite material, especially when the service temperature exceeds 400°C, the strengthening effect decays sharply, which greatly limits the actual production process of copper-based composite materials strengthened with a single alloy element.

[0004] Patent publication number CN118360518A proposes a method for preparing a high-speed rail brake shoe composite material based on a copper-based high-temperature strengthening design. The method uses a Cu-7.0Ni-1.75Si-0.5Cr alloy mixed with pure copper as the matrix, precipitating Cr3Si and Ni2Si strengthening phases for high-speed rail brake shoes. Because the matrix contains pure copper (0-50%), incomplete alloying occurs, and the pure copper phase easily softens at high temperatures, affecting overall strength.

[0005] Patent publication number CN118516585A proposes a high-temperature-resistant powder metallurgy copper-based brake pad and its preparation method. This method uses liquid-phase mixing and in-situ carbonization to create a nano-hafnium carbide dispersion-strengthened copper alloy, which is then combined with other components to create a high-temperature-resistant brake pad. Due to the significant difference in thermal expansion coefficients between the nanoparticles and the copper matrix, long-term high-temperature service can easily lead to interfacial cracking, impacting reliability.

[0006] Patent publication number CN104525949A proposes a highly wear-resistant copper-based friction composite material and its preparation method. The material uses a Cu-Fe-Cr matrix and ZTA composite ceramic as a reinforcement, using powder metallurgy to produce the highly wear-resistant material. However, due to its reliance on exogenous ceramic particles for composite reinforcement, the material suffers from the problem of weakly bonded ceramic particles easily falling off at the interface, resulting in poor friction stability during high-speed braking and an inability to improve high-temperature strength and friction coefficient stability at the matrix level.

[0007] Patent publication number CN101348874A proposes a high-performance copper-based alloy material and its preparation method. Based on a Cu-Ni-Si-Zr alloy, the high-strength and high-conductivity copper alloy is produced through smelting, hot forging, solutionizing, and graded aging. The alloy is intended for lead frame applications. Due to the lack of high-energy ball milling and vacuum hot pressing, the uniform distribution of the reinforcing phase cannot be achieved, making it difficult to meet the interfacial bonding strength requirements of friction materials.

[0008] This work was supported by the Natural Science Foundation of Jiangxi Province (20242BAB25272) and the Open Fund of the National Laboratory for Safety and Resilience of Mountain Civil Engineering (HJGZ202402). Summary of the Invention

[0009] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a method for preparing an alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-speed rail brake pads. The alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-speed rail brake pads is prepared by powder metallurgy, which solves the problems of the current copper-based composite materials for high-speed rail brake pads, such as low friction coefficient, unstable friction coefficient and high wear rate at high temperature.

[0010] In order to achieve the above object, the present invention adopts the following technical solutions:

[0011] The invention discloses a method for preparing a high-temperature and high-strength copper alloy-based composite material for alloy-reinforced high-speed railway brake pads. The method adopts the alloying element Si to strengthen the Cu-Ni-Al alloy, and uses the Cu-Ni-Al-Si alloy as the matrix, FeCu30 as the matrix strengthening component, graphite and MoS2 as the friction-reducing components, and SiO2 and CrFe as the friction-increasing components. The mass percentage of each raw material is as follows: 40-60wt.% Cu-Ni-Al-Si alloy powder, 20-35wt.% FeCu30 powder, 5-15wt.% CrFe powder, 5-20wt.% graphite powder, 0.5-5wt.% MoS2 powder, and 0.5-5wt.% SiO2 powder. After the above raw material powders are uniformly mixed, they are cold-pressed and hot-pressed sintered under vacuum conditions.

[0012] The preparation method of the alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-speed rail brake pads is as follows: Cu-Ni-Al-Si alloy powder is prepared by high-energy ball milling, the ball-to-material mass ratio is 2:1-10:1, the ball milling speed is 320-420 rpm, and the ball milling time is 10-20 hours.

[0013] The method for preparing the alloy-reinforced high-temperature high-strength copper alloy-based composite material for high-speed rail brake pads is as follows: the high-temperature strengthening phases precipitated from the Cu-Ni-Al-Si alloy powder after ball milling are Ni-Al phase and Ni-Si phase.

[0014] The preparation method of the alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-speed rail brake pads is as follows: the raw material composition and mass percentage of each component of the Cu-Ni-Al-Si alloy powder are as follows: Cu powder 30-50wt.%, Ni powder 8-15wt.%, Al powder 1-4wt.%, Si powder 0.05-1wt.%.

[0015] The method for preparing the alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-speed rail brake pads comprises the following steps:

[0016] S1. Powder pretreatment

[0017] Cu powder, Ni powder, Al powder, and Si powder were weighed according to weight: Cu powder 30-50 wt.%, Ni powder 8-15 wt.%, Al powder 1-4 wt.%, and Si powder 0.05-1 wt.%, followed by high-energy ball milling to obtain Cu-Ni-Al-Si alloy powder;

[0018] S2. Ingredients and Mixing

[0019] Various powders are weighed according to the following weight ratios: 40-60 wt.% Cu-Ni-Al-Si alloy powder, 20-35 wt.% FeCu30 powder, 5-15 wt.% CrFe powder, 5-20 wt.% graphite powder, 0.5-5 wt.% MoS2 powder, and 0.5-5 wt.% SiO2 powder; the raw material powders are then placed in a V-type mixer, and a binder is added at a ratio of 0.2-0.4% of the total weight of the powders to uniformly mix the powders to obtain a mixed raw material;

[0020] S3, cold pressing

[0021] The mixed raw material obtained in step S2 is placed in a cold pressing mold and pressed into a green body at a pressing pressure of 400 to 500 MPa;

[0022] S4, hot pressing sintering

[0023] The green compact obtained in S3 is placed in a vacuum hot pressing sintering furnace and sintered to obtain the high-temperature and high-strength copper alloy-based composite material.

[0024] The method for preparing the high-temperature and high-strength copper alloy-based composite material for alloy-reinforced high-speed railway brake pads has a raw material powder particle size range of -150 to +300 meshes.

[0025] In the method for preparing the alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-speed rail brake pads, in step S2, liquid paraffin is used as the binder to promote uniform mixing of the powder.

[0026] The preparation method of the alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-speed rail brake pads, in step S4, hot pressing sintering is carried out under a vacuum pressure lower than 0.2 Pa, the sintering temperature is 800-1000°C, the sintering pressure is 5-6.5MPa, and the heat preservation and pressure holding time is 2-5h.

[0027] The preparation method of the alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-speed railway gate pads is tested for the performance of the high-temperature and high-strength copper alloy-based composite material for high-speed railway gate pads. Its performance indicators are: hardness 40-60HB, compressive strength 110-150MPa, friction coefficient 0.3-0.6 and wear rate 0.2-0.6mg / m at room temperature, and friction coefficient 0.3-0.6 and wear rate 1.0-1.8mg / m at high temperature.

[0028] The design idea of ​​the present invention is:

[0029] This invention utilizes a matrix alloy strengthening method to prepare a high-temperature, high-strength copper alloy-based composite material for high-speed rail brake pads. The invention proposes strengthening a high-temperature, high-strength Cu-Ni-Al alloy with the alloying element Si. Using a Cu-Ni-Al-Si alloy as the matrix material, the alloy powder is prepared via high-energy ball milling. The addition of multiple alloying elements, such as Ni, Al, and Si, synergistically forms a γ-Cu solid solution and high-temperature strengthening phases, including Ni-Al and Ni-Si phases. These phases not only significantly improve the strength and hardness of the copper matrix but also maintain stable performance at high temperatures, preventing the material from softening at high temperatures and causing performance degradation. The invention combines solid solution strengthening with secondary phase strengthening. Elements such as Ni, Al, and Si form a solid solution in the copper matrix, producing a solid solution strengthening effect. Al promotes the precipitation of the Ni-Al phase, enhancing high-temperature stability. Si dissolves in the Cu-Ni matrix, producing solid solution strengthening and forming a nanoscale Ni-Si phase with Ni. Simultaneously, the precipitated Ni-Al and Ni-Si phases, acting as secondary phases, further enhance the strength and hardness of the matrix, improving the material's wear resistance and high-temperature stability.

[0030] The present invention adopts powder metallurgy to prepare, and the specific process includes the steps of powder pretreatment, material mixing, cold pressing and hot pressing sintering. The Cu-Ni-Al-Si alloy powder is processed by high-energy ball milling, and the ball-to-material ratio, ball milling speed and ball milling time are accurately controlled to ensure the uniformity and high quality of the alloy powder. This process can fully diffuse the alloy elements and precipitate high-temperature strengthening phases, providing high-quality matrix materials for subsequent composite material preparation. During the hot pressing sintering process, parameters such as vacuum degree, sintering temperature, sintering pressure and heat preservation and pressure holding time are strictly controlled to ensure the densification and performance uniformity of the composite material. Thus, by optimizing these process parameters, the mechanical properties and tribological properties of the material can be further improved.

[0031] The present invention incorporates FeCu30 powder as a matrix-strengthening component, CrFe powder and SiO2 powder as wear-increasing components, and graphite (flake) and MoS2 powder as wear-reducing components. These components work synergistically within the composite material, improving both its strength and hardness while also regulating its friction coefficient and reducing its wear rate. Furthermore, by optimizing the ratios of the various components, the composite material maintains a stable friction coefficient and low wear rate at high temperatures, while also taking into account its thermal conductivity and resistance to high-temperature softening, enabling long-term stable operation in high-speed rail braking systems.

[0032] Compared with the prior art, the advantages and beneficial effects of the present invention are:

[0033] 1. The present invention provides an alloy-reinforced, high-temperature, high-strength copper alloy-based composite material for high-speed rail brake pads. This material strengthens a Cu-Ni-Al alloy by introducing the alloying element Si. The alloying elements synergistically form a high-temperature stable strengthening phase, forming a γ-Cu solid solution, Ni-Al phases, and Ni-Si phases within the matrix alloy, resulting in both solid solution strengthening and secondary phase strengthening. Compared to existing strengthening technologies, the present invention offers a simpler preparation method, environmentally friendly raw materials, lower production costs, and superior economic benefits.

[0034] 2. This invention uses high-energy ball milling (ball-to-material ratio 2:1-10:1, rotation speed 320-420 rpm) to prepare the Cu-Ni-Al-Si alloy. This introduces Ni-Al and Ni-Si high-temperature strengthening phases, achieving mechanical alloying of the powders and causing the Ni-Al / Ni-Si phase to precipitate at the nanoscale. Compared to existing composite strengthening methods, this improves the interfacial bonding strength between the strengthening phase and the matrix.

[0035] 3. The present invention uses vacuum hot pressing sintering (vacuum pressure is lower than 0.2 Pa, sintering temperature is 800-1000°C, and sintering pressure is 5-6.5 MPa) to eliminate the pores between powders and improve density on the one hand, and on the other hand promote the atomic diffusion between the reinforcing phase and the matrix to form a metallurgical bonding interface, ensuring that the reinforcing phase is not easy to fall off at high temperature.

[0036] 4. The present invention adopts Cu-Ni-Al-Si alloy as the matrix of the copper-based composite material to obtain a high-temperature and high-strength copper alloy-based composite material. Compared with the existing copper-based composite materials, the high-temperature and high-strength copper alloy-based composite material has a more stable friction coefficient and a lower wear rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is the microstructure of high-temperature and high-strength copper alloy-based composite materials.

[0038] Figure 2 2 is the X-ray diffraction (XRD) pattern of the Cu-Ni-Al-Si matrix alloy; in the figure, the abscissa 2θ is the diffraction angle (degree), and the ordinate Intensity is the relative intensity (au).

[0039] Figure 3 Scanning electron microscope (SEM) images of the Cu-Ni-Al-Si matrix alloy; (a) is the morphology image, and (b) is the distribution map of Cu, Ni, Al, and Si elements. DETAILED DESCRIPTION

[0040] In a specific implementation process, the present invention prepares a high-temperature, high-strength copper alloy-based composite material for high-speed rail brake pads reinforced with alloy by powder metallurgy, adopts alloying element Si to strengthen Cu-Ni-Al alloy, and uses Cu-Ni-Al-Si alloy as matrix material, FeCu30 as matrix reinforcement component, graphite (flake) and MoS2 as friction-reducing components, SiO2 and CrFe as friction-increasing components, and the mass percentage of each raw material is as follows: 40-60wt.% Cu-Ni-Al-Si alloy powder, 20-35wt.% FeCu30 powder, 5-15wt.% CrFe powder, 5-20wt.% graphite powder, 0.5-5wt.% MoS2 powder, and 0.5-5wt.% SiO2 powder. After the above raw material powders are uniformly mixed, they are cold-pressed and subsequently sintered under vacuum, high-temperature and high-pressure conditions.

[0041] The present invention is further described in detail below through examples and drawings.

[0042] Example 1

[0043] In this embodiment, a method for preparing a high-temperature, high-strength copper alloy-based composite material for alloy-reinforced high-speed rail brake pads is provided. The raw material powders are weighed by mass percentage as follows: 48% Cu-Ni-Al-Si alloy powder, 29% FeCu30 powder, 9% CrFe powder, 11% graphite (flakes), 1.5% MoS2 powder, and 1.5% SiO2 powder. The particle size range of the raw material powders is -150 to +300 mesh (the powder particles can pass through a 150-mesh sieve and cannot pass through a 300-mesh sieve). After the raw material powders are evenly mixed, they are cold-pressed and then sintered under vacuum, high-temperature, and high-pressure conditions. The method mainly includes the following steps:

[0044] S1. Powder pretreatment

[0045] Weigh Cu, Ni, Al, and Si powders by weight: 37.75% Cu, 8.72% Ni, 1.33% Al, and 0.20% Si. Place the powders in a ball mill at a ball-to-material ratio of 3:1. Set the mill speed to 350 rpm for 20 hours. Stop milling every 5 hours and then continue milling after 1 hour.

[0046] S2. Ingredients and Mixing

[0047] Various powders are placed in a V-type mixer in a weight ratio of: 48% Cu-Ni-Al alloy powder, 29% FeCu30 powder (the copper content in FeCu30 powder is about 30wt.%, and the rest is iron), 9% CrFe powder (the chromium content in CrFe powder is about 40wt.%, and the rest is iron), 1.5% SiO2 powder, 11% graphite (flakes) and 1.5% MoS2 powder. Liquid paraffin is added as a binder at 0.3% of the total mass of all powders, and the mixture is taken out after mixing for 4 hours.

[0048] S3, cold pressing

[0049] The mixed powder is loaded into the cold pressing mold according to the calculated weight and cold pressed at a pressure of 470 MPa for 30 seconds to ensure that the ingredients are highly consistent after molding.

[0050] S4, hot pressing sintering

[0051] The cold-pressed green body was placed in a vacuum hot-pressing sintering furnace and hot-pressed at a vacuum pressure of 0.1 Pa. The sintering temperature was 1000°C, the sintering pressure was 5.9 MPa, and the holding time was 4 hours. The pressure was maintained constant during the cooling process. After the furnace cooled to room temperature, the green body was removed to form a high-temperature, high-strength copper alloy-based composite material for high-speed rail brake pads.

[0052] Performance Testing: The prepared high-temperature, high-strength copper alloy-based composite material was tested for hardness, compressive strength, and tribological properties. The results were as follows: a hardness of 52 HB, a compressive strength of 147 MPa, a friction coefficient of 0.53 and a wear rate of 0.33 mg / m at room temperature, and a friction coefficient of 0.49 and a wear rate of 1.21 mg / m at high temperature. Compared with Cu-Ni-Al-based composites, the hardness increased by 8%, the compressive strength increased by 2%, the wear rate decreased by 15% at room temperature, and by 16% at high temperature. Compared with pure copper-based composites, the hardness increased by 13%, the compressive strength increased by 24%, the wear rate decreased by 31% at room temperature, and by 57% at high temperature.

[0053] like Figure 1 As shown in the microstructure of the high-temperature, high-strength copper alloy-based composite, it can be seen that the composite consists of three components: a matrix component, a friction-reducing component, and a friction-enhancing component. The friction-enhancing component increases frictional resistance and adjusts the friction coefficient, while the friction-reducing component effectively reduces the friction coefficient and improves wear resistance. After hot pressing and sintering, each component is evenly distributed in the matrix and tightly bonded to it.

[0054] like Figure 2 As shown in the figure, it can be seen from the XRD pattern of Cu-Ni-Al-Si alloy that the Cu-Ni-Al-Si alloy is composed of γ-Cu solid solution and Ni3Al precipitation phase. The solute atoms Ni, Al, and Si cause severe distortion of the Cu lattice, and Ni3Al produces a coherent stress field, which hinders dislocation movement.

[0055] like Figure 3 As shown in the SEM image of Cu-Ni-Al-Si alloy, Si exists in the form of solid solution and Ni-Si intermetallic compound.

[0056] Implementation results show that the present invention uses alloy strengthening technology to prepare a high-temperature, high-strength copper alloy-based composite material to address the low friction coefficient, instability, and high wear rate of existing copper-based composite materials used in high-speed rail brake pads at high temperatures, while also improving the overall material performance. The high-temperature, high-strength copper alloy-based composite material has higher hardness and compressive strength than pure copper-based composite materials, a more stable friction coefficient, and a lower wear rate. Compared with commercial pure copper-based composite materials and Cu-Ni-Al-based composite materials, the high-temperature, high-strength Cu-Ni-Al-Si-based composite material has increased hardness and strength, significantly improved friction coefficient stability, and wear resistance, meeting the stringent material requirements of high-speed rail braking systems.

Claims

1. A method for preparing a high-temperature and high-strength copper alloy-based composite material for alloy-reinforced high-speed railway brake pads, characterized in that: The invention adopts the alloying element Si to strengthen the Cu-Ni-Al alloy, and takes the Cu-Ni-Al-Si alloy as the matrix, FeCu30 as the matrix strengthening component, graphite and MoS2 as the wear-reducing components, SiO2 and CrFe as the wear-increasing components, and the mass percentage of each raw material is as follows: 40-60wt.% Cu-Ni-Al-Si alloy powder, 20-35wt.% FeCu30 powder, 5-15wt.% CrFe powder, 5-20wt.% graphite powder, 0.5-5wt.% MoS2 powder, and 0.5-5wt.% SiO2 powder; after the above raw material powders are uniformly mixed, cold pressed into shape and hot pressed and sintered under vacuum conditions.

2. The method for preparing the alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-speed rail brake pads according to claim 1, characterized in that: The Cu-Ni-Al-Si alloy powder is prepared by a high-energy ball milling method, with a ball-to-material mass ratio of 2:1 to 10:1, a ball milling speed of 320 to 420 rpm, and a ball milling time of 10 to 20 hours.

3. The method for preparing the alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-speed rail brake pads according to claim 2, characterized in that: The high temperature strengthening phases precipitated in the Cu-Ni-Al-Si alloy powder after ball milling are Ni-Al phase and Ni-Si phase.

4. The method for preparing the alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-speed rail brake pads according to claim 1, characterized in that: The raw material composition and mass percentage of each component for preparing Cu-Ni-Al-Si alloy powder are as follows: Cu powder 30-50wt.%, Ni powder 8-15wt.%, Al powder 1-4wt.%, Si powder 0.05-1wt.%.

5. The method for preparing the alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-speed rail brake pads according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. Powder pretreatment Cu powder, Ni powder, Al powder, and Si powder were weighed according to weight: Cu powder 30-50 wt.%, Ni powder 8-15 wt.%, Al powder 1-4 wt.%, and Si powder 0.05-1 wt.%, followed by high-energy ball milling to obtain Cu-Ni-Al-Si alloy powder; S2. Ingredients mixing Various powders are weighed according to the following weight ratios: 40-60 wt.% Cu-Ni-Al-Si alloy powder, 20-35 wt.% FeCu30 powder, 5-15 wt.% CrFe powder, 5-20 wt.% graphite powder, 0.5-5 wt.% MoS2 powder, and 0.5-5 wt.% SiO2 powder; the raw material powders are then placed in a V-type mixer, and a binder is added at a ratio of 0.2-0.4% of the total weight of the powders to uniformly mix the powders to obtain a mixed raw material; S3, cold pressing The mixed raw material obtained in step S2 is placed in a cold pressing mold and pressed into a green body at a pressing pressure of 400 to 500 MPa; S4, hot pressing sintering The green compact obtained in S3 is placed in a vacuum hot pressing sintering furnace and sintered to obtain the high-temperature and high-strength copper alloy-based composite material.

6. The method for preparing the alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-speed rail brake pads according to claim 5, characterized in that: The particle size range of the raw material powder is -150 to +300 mesh.

7. The method for preparing the alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-speed rail brake pads according to claim 5, characterized in that: In step S2, liquid paraffin is used as a binder to promote uniform mixing of the powders.

8. The method for preparing the alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-speed rail brake pads according to claim 5, characterized in that: In step S4, hot pressing sintering is performed under a vacuum pressure of less than 0.2 Pa, the sintering temperature is 800-1000° C., the sintering pressure is 5-6.5 MPa, and the heat and pressure holding time is 2-5 hours.

9. The method for preparing the alloy-reinforced high-temperature and high-strength copper alloy-based composite material for high-speed rail brake pads according to claim 5, characterized in that: The performance of high-temperature and high-strength copper alloy-based composite materials used for high-speed railway gate pads was tested, and its performance indicators are: hardness 40~60HB, compressive strength 110~150MPa, friction coefficient 0.3~0.6 and wear rate 0.2~0.6mg / m at room temperature, friction coefficient 0.3~0.6 and wear rate 1.0~1.8mg / m at high temperature.

Images