Preparation method of pincer type structure carbon ceramic friction plate and product

Abstract

The invention belongs to the field of carbon-ceramic friction plates, and discloses a preparation method and a product of a pincer type structure carbon-ceramic friction plate, the method comprises the following steps: mixing phenolic resin, titanium carbide, boron nitride, silicon carbide, graphite and carbon fiber to obtain first mixed powder; adding the first mixed powder into a mold, and preheating to obtain a blank; sequentially putting the blank into a drying oven, a cracking furnace and a heat treatment furnace for pretreatment to obtain a porous preform; performing vacuum infiltration treatment on the porous preform and the second mixed powder to obtain a carbon-ceramic friction plate; the second mixed powder is composed of FeSi85 and Cu, and the mass ratio of the FeSi85 to the Cu is 90: 10; titanium carbide reacts with silicon in the infiltration process to generate Ti3SiC2, and Ti3SiC2 has the characteristics of metal and ceramic, has high melting point, high strength, high thermal conductivity and high toughness, and can effectively stabilize the friction process and reduce the fluctuation of the friction coefficient.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of carbon ceramic friction plates and relates to a preparation method of a carbon ceramic friction plate with a clamp structure and a product. BACKGROUND

[0002] With the continuous improvement of the performance requirements of various transportation systems on the braking system, carbon ceramic friction materials have become an ideal choice to replace traditional metal friction materials due to their advantages of light weight, excellent high-temperature performance and long service life. At present, carbon ceramic self-matching structures have been applied in aircraft braking systems and have shown excellent performance. In the clamp braking structure, unlike the disc braking structure commonly used in aircraft, the clamp structure has special and differentiated requirements for the performance of the friction pair. Specifically, it needs to have high strength characteristics to ensure the strength and stability of the overall structure; the strength requirement of the friction plate is relatively low, and the design allows the plate body to wear, and such wear needs to be controllable, and the brake disc needs to be as little worn as possible or only slightly worn.

[0003] However, the existing preparation process of carbon ceramic friction pairs cannot meet these specific requirements of the clamp structure. The full carbon ceramic friction pairs prepared by the current process have homogenization characteristics in terms of wear performance, and cannot achieve differentiated and precise regulation of the wear resistance between the brake disc and the friction plate, and the friction performance is also difficult to adjust and match, which seriously restricts the effective application of carbon ceramic friction materials in the clamp braking structure.

[0004] Although carbon ceramic brake discs have been widely used in high-end passenger cars, racing cars and other high-end braking scenes, the friction plates matched with them are mainly resin-based friction materials. Although they can meet the needs of regular braking, they cannot fully utilize the high-temperature performance advantages of carbon ceramic brake discs. Resin-based friction plates are prone to thermal recession in an environment above 400°C, resulting in a sharp decline in braking performance; in the working conditions of continuous high-intensity braking such as racing cars and heavy trucks, there may also be safety hazards such as delayed braking response, which seriously threatens the safety of driving.

[0005] Carbon ceramic friction plates are usually prepared by combining a three-dimensional needled carbon fiber preform and a silicon carbide (SiC) matrix using a chemical vapor infiltration (CVI) or liquid silicon infiltration (LSI) process. However, the phase composition of the carbon ceramic friction pair prepared by this method is simple, mainly including SiC, Si, carbon fibers and pyrolytic carbon, and the performance regulation range is narrow, making the friction and wear performance of the full carbon ceramic friction pair of the clamp structure less adaptable, and unable to meet the special requirements of the clamp braking structure for the performance of the friction pair. SUMMARY

[0006] In view of the deficiencies of the prior art, the purpose of the present application is to provide a preparation method of a carbon ceramic friction plate with a clamp structure and a product.

[0007] In order to achieve the above object, the present application adopts the following technical solutions: The present application provides a preparation method of a clamp structure carbon ceramic friction plate, comprising: mixing phenolic resin, titanium carbide, boron nitride, silicon carbide, graphite and carbon fiber to obtain first mixed powder; adding the first mixed powder into a mold for preheating to obtain a blank; sequentially placing the blank into an oven, a cracking furnace and a heat treatment furnace for pretreatment to obtain a porous preform; and performing vacuum infiltration treatment on the porous preform and second mixed powder to obtain the carbon ceramic friction plate.

[0008] Further, the first mixed powder comprises the following components in percentage by mass: phenolic resin 15-40%; titanium carbide 5-20%; boron nitride 5-10%; silicon carbide 5-20%; graphite 20-40%; and carbon fiber 15-25%.

[0009] Further, the second mixed powder is composed of FeSi85 and Cu; and the mass ratio of FeSi85 to Cu is 90:10.

[0010] Further, the preheating comprises: first preheating, second preheating and third preheating; the first preheating is performed for 3-5 times, the temperature of the first preheating is 80℃, the pressure of the first preheating is 5-10 Mpa, and the pre-pressing time is 30 s; the second preheating is performed for 3-5 times; the temperature of the second preheating is 120℃, the pressure of the second preheating is 10-15 Mpa, and the pre-pressing time is 30 s; the third preheating is performed for 3-5 times; the temperature of the third preheating is 180℃, the pressure of the third preheating is 20-30 Mpa, and the pre-pressing time is 30 s.

[0011] Further, the sequentially placing the blank into an oven, a cracking furnace and a heat treatment furnace for pretreatment comprises: placing the blank into the oven for solidification treatment, placing the solidified blank into the cracking furnace for cracking in a vacuum environment or by introducing inert gas, and placing the cracked blank into the heat treatment furnace.

[0012] Further, the temperature of the oven is 220℃, and the solidification time is 1-3 h; the temperature of the cracking is 900℃, and the time is 1 h; and the temperature of the heat treatment furnace is 1800-2400℃, and the time is 1-2 h.

[0013] Further, the temperature of the cracking is raised to 900℃ at a rate of 3-5℃ / min, and the temperature of the heat treatment furnace is raised to 1800-2400℃ at a rate of 5-10℃ / min.

[0014] Further, the vacuum infiltration treatment of the porous preform and the second mixed powder obtains the carbon ceramic friction plate, comprising: placing the porous preform on the second mixed powder to obtain a composite structure; placing the composite structure in a graphite crucible, and sequentially performing vacuum and infiltration treatment to obtain the carbon ceramic friction plate, wherein the temperature of the graphite crucible is 1400-1600℃.

[0015] Further, the graphite crucible is heated to 1400-1600℃ at a rate of 5-10℃ / min.

[0016] The application also provides a carbon ceramic friction plate prepared by the preparation method.

[0017] Compared with the prior art, the application has the following beneficial technical effects: The first mixed powder is obtained by mixing phenolic resin, titanium carbide, boron nitride, silicon carbide, graphite and carbon fiber, titanium carbide reacts with silicon to generate Ti3SiC2 in the infiltration process, Ti3SiC2 has the characteristics of both metal and ceramic, has high melting point, high strength, high thermal conductivity and high toughness, can effectively stabilize the friction process and reduce the fluctuation of the friction coefficient; the phase composition and microstructure of the carbon ceramic friction plate can be flexibly regulated by adjusting the components and proportions of the first mixed powder and the second mixed powder, the shortcomings of single phase composition and narrow performance regulation range of the traditional method are overcome, the special requirements of the pincer brake structure on the friction pair can be met, and the carbon ceramic friction plate has a short preparation period and can be mass-produced.

[0018] The second mixed powder of silicon-iron alloy and copper is used in the infiltration process, the damage of the silicon-iron alloy to the disc is smaller than that of pure silicon, and the introduction of copper can make the friction film more easily formed during the friction process, stabilize the friction performance and reduce the wear.

[0019] The application introduces boron nitride into the first mixed powder, utilizes the inherent non-wetting property of boron nitride and silicon or silicon alloy to form controllable interfacial resistance in the vacuum infiltration process, and avoids excessive infiltration; the boron nitride can realize infiltration filling in the vacuum infiltration process, make the iron-silicon alloy react with Si to generate SiC, and does not affect the overall mechanical properties of the material. The structural integrity and thermal stability of the composite material matrix are further enhanced, which lays a foundation for the stable work of the carbon ceramic friction plate under high temperature and high load. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The flowchart of the application is shown in the figure; Figure 2 The SEM photo of the surface microstructure of the carbon ceramic friction plate of Example 2 is shown in the figure. Figure 3 SEM photos of the surface micro-morphology of the carbon ceramic friction plate of the embodiment 5 of the present application; Figure 4 SEM photos of the surface micro-morphology of the carbon ceramic friction plate of the embodiment 5 of the present application; Figure 5 Braking curve diagram of 6 times braking of the carbon ceramic friction plate of the embodiment 4 of the present application. DETAILED DESCRIPTION

[0021] In order to make the personnel in the technical field better understand the present application scheme, the technical scheme in the embodiment of the present application will be described clearly and completely in the following by combining the drawings in the embodiment of the present application. Obviously, the described embodiment is only a part of the embodiment of the present application, not all. Based on the embodiment in the present application, all other embodiments obtained by the person skilled in the art without creative labor should belong to the scope of protection of the present application.

[0022] Embodiment 1 The present application is a kind of preparation method of carbon ceramic friction plate of clamp structure, comprising: phenolic resin, titanium carbide, boron nitride, silicon carbide, graphite and carbon fiber are mixed to obtain first mixed powder;First mixed powder is added to the mold and preheating to obtain blank embryo;The blank embryo is sequentially put into oven, pyrolysis furnace, heat treatment furnace for pretreatment to obtain porous preform;The porous preform is treated by vacuum infiltration with second mixed powder to obtain carbon ceramic friction plate.

[0023] Phenolic resin, titanium carbide, boron nitride, silicon carbide, graphite and carbon fiber are mixed to obtain first mixed powder. Specifically: 15-40wt% phenolic resin, 5-20wt% titanium carbide, 5-10wt% boron nitride, 5-20wt% silicon carbide, 20-40wt% graphite are first mixed 1 2h, then add 15-25wt% carbon fiber, continue to mix until uniform, to obtain mixed powder.

[0024] The first mixed powder is added to the mold and preheated to obtain a blank. Specifically, first, the release agent is evenly applied on the mold, then the first mixed powder is added, and the mold with the first mixed powder is placed in the hot press for preheating treatment. The preheating treatment includes first preheating, second preheating and third preheating. The parameters of the first preheating are as follows: the temperature of the hot press is raised to 80℃, the pressure is adjusted to 5-10 Mpa for prepressing for 30s, and the process is repeated for 3-5 times. The parameters of the second preheating are as follows: the temperature of the hot press is raised to 120℃, the pressure is adjusted to 10-15 Mpa for prepressing for 30s, and the process is repeated for 3-5 times. The parameters of the third preheating are as follows: the temperature of the hot press is raised to 180℃, the pressure is adjusted to 20-30 Mpa for prepressing for 30s, and the process is repeated for 3-5 times. After the third preheating, the pressure is kept unchanged for 20 min, and the blank is obtained after demolding.

[0025] The blank is sequentially placed in an oven, a pyrolysis furnace and a heat treatment furnace for pretreatment to obtain a porous preform. Specifically, the blank is placed in the oven and cured at 220℃ for 1-3h; the cured blank is placed in the pyrolysis furnace, heated to 900℃ at a heating rate of 3-5℃ / min in a vacuum environment or by introducing inert gas, and kept for 1h for pyrolysis; the pyrolyzed blank is placed in the heat treatment furnace, vacuumed, heated to 1800-2400℃ at a heating rate of 5-10℃ / min, kept for 1-2h, and then naturally cooled down with the furnace to obtain the porous preform.

[0026] The porous preform is subjected to vacuum infiltration treatment with the second mixed powder to obtain the carbon ceramic friction plate. Specifically, the porous preform is placed on the second mixed powder to obtain a composite structure; the composite structure is placed in a graphite crucible, and then subjected to vacuum and infiltration treatment to obtain the carbon ceramic friction plate. The temperature of the graphite crucible is 1400-1600℃, and the temperature of the graphite crucible is raised at a rate of 5-10℃ / min. The second mixed powder is composed of FeSi85 and Cu, and the mass ratio of FeSi85 to Cu is 90:10.

[0027] Example 2 The present application discloses a preparation method of a carbon ceramic friction plate with a clamp structure. 35wt% of phenolic resin, 5wt% of titanium carbide, 10wt% of boron nitride, 5wt% of silicon carbide and 20wt% of graphite are first mixed for 1h, and then 25wt% of carbon fiber is added and mixed until uniform to obtain a first mixed powder.

[0028] First, evenly apply the demoulding agent to the mold. Then, add the first powder mixture and place the mold with the first powder mixture in a hot press for preheating. The preheating process includes the first, second, and third preheating. The parameters for the first preheating are as follows: heat the hot press to 80°C, adjust the pressure to 5 MPa, and pre-press for 30 seconds, repeating three times. The parameters for the second preheating are as follows: heat the hot press to 120°C, adjust the pressure to 10 MPa, and pre-press for 30 seconds, repeating five times. The parameters for the third preheating are as follows: heat the hot press to 180°C, adjust the pressure to 20 MPa, and pre-press for 30 seconds, repeating three times. After the third preheating, maintain the pressure constant for 20 minutes. After demolding, the blank is obtained.

[0029] The green blank is placed in an oven and cured at 220°C for 3 hours. The cured green blank is placed in a cracking furnace and heated to 900°C at a heating rate of 3°C / min in a vacuum environment or with the passage of inert gas, and kept at this temperature for 1 hour to undergo cracking. The cracked green blank is placed in a heat treatment furnace, which is first evacuated and then heated to 1800°C at a heating rate of 5°C / min. After being kept at this temperature for 2 hours, the temperature is naturally lowered with the furnace to obtain a porous preform.

[0030] The porous preform is placed on the second mixed powder to form a composite structure. The composite structure is then placed in a graphite crucible and subjected to vacuum and infiltration treatments to form a carbon-ceramic friction plate. The graphite crucible temperature is 1450°C and increased at a rate of 5°C / min. The second mixed powder consists of FeSi85 and Cu, with a mass ratio of FeSi85 to Cu of 90:10.

[0031] The surface micromorphology SEM photos of the carbon ceramic friction plate prepared according to the above steps are as follows: Figure 2 As shown, the dark black area is graphite, the dark gray is SiC, and the gray area is the FeSi2 phase. The black area contains encapsulated BN. Due to BN's poor wettability, a high content can lead to incomplete infiltration and unfilled pores on the surface. However, the overall material is relatively dense and does not affect its mechanical properties. SiC exists in two forms: one is generated by reaction, and the other is free SiC introduced into the material during hot pressing.

[0032] Example 3 The present invention discloses a method for preparing a clamp-type carbon-ceramic friction plate. The method comprises the following steps: firstly mixing 15 wt% of phenolic resin, 5 wt% of titanium carbide, 10 wt% of boron nitride, 20 wt% of silicon carbide, and 30 wt% of graphite for 1 hour, then adding 20 wt% of carbon fiber, and continuing to mix until uniform, to obtain a first mixed powder.

[0033] Firstly, the demolding machine is evenly applied on the mold, then the first mixed powder is added, and the mold with the first mixed powder is put into the hot press for preheating treatment. The preheating treatment includes first preheating, second preheating and third preheating. The parameters of the first preheating are as follows: the hot press is heated to 80℃, the pressure is adjusted to 10Mpa for pre-pressing for 30s, and the process is repeated for 3 times. The parameters of the second preheating are as follows: the hot press is heated to 120℃, the pressure is adjusted to 15Mpa for pre-pressing for 30s, and the process is repeated for 5 times. The parameters of the third preheating are as follows: the hot press is heated to 180℃, the pressure is adjusted to 30Mpa for pre-pressing for 30s, and the process is repeated for 3 times. After the third preheating, the pressure is kept unchanged for 20min, and the green body is obtained after demolding.

[0034] The green body is placed in an oven and cured at 220℃ for 1h; the cured green body is placed in a cracking furnace, heated to 900℃ at a rate of 5℃ / min in a vacuum environment or by introducing inert gas, and kept for 1h for cracking; the cracked green body is placed in a heat treatment furnace, vacuumed first, then heated to 2400℃ at a rate of 10℃ / min, kept for 1h, and naturally cooled down with the furnace, to finally obtain a porous preform.

[0035] The porous preform is placed on the second mixed powder to obtain a composite structure; then the composite structure is placed in a graphite crucible, and vacuum and infiltration treatment are sequentially performed to obtain a carbon ceramic friction plate. The temperature of the graphite crucible is 1450℃, and the temperature of the graphite crucible rises at a rate of 10℃ / min. The second mixed powder is composed of FeSi85 and Cu, and the mass ratio of FeSi85 to Cu is 90:10.

[0036] Example 3 is similar to Example 2, and the content of phenolic resin is reduced, so that the FeSi2 phase and the SiC generated by reaction are reduced.

[0037] Example 4 A preparation method of a clamp type carbon ceramic friction plate is provided. 25wt% of phenolic resin, 10wt% of titanium carbide, 5wt% of boron nitride, 10wt% of silicon carbide and 25wt% of graphite are first mixed for 1h, and then 25wt% of carbon fiber is added and mixed until uniform to obtain a first mixed powder.

[0038] Firstly, the demolding machine is evenly applied on the mold, then the first mixed powder is added, and the mold with the first mixed powder is put into the hot press for preheating treatment. The preheating treatment includes first preheating, second preheating and third preheating. The parameters of the first preheating are as follows: the hot press is heated to 80℃, the pressure is adjusted to 8Mpa for prepressing for 30s, and the process is repeated for 5 times. The parameters of the second preheating are as follows: the hot press is heated to 120℃, the pressure is adjusted to 13Mpa for prepressing for 30s, and the process is repeated for 5 times. The parameters of the third preheating are as follows: the hot press is heated to 180℃, the pressure is adjusted to 25Mpa for prepressing for 30s, and the process is repeated for 5 times. After the third preheating, the pressure is kept unchanged for 20min, and the green body is obtained after demolding.

[0039] The green body is placed in an oven and cured at 220℃ for 2h; the cured green body is placed in a cracking furnace, heated to 900℃ at a rate of 4℃ / min in a vacuum environment or by introducing inert gas, and kept for 1h for cracking; the cracked green body is placed in a heat treatment furnace, vacuumed first, then heated to 2000℃ at a rate of 7℃ / min, kept for 2h, and naturally cooled down with the furnace, finally obtaining a porous preform.

[0040] The porous preform is placed on the second mixed powder to obtain a composite structure; then the composite structure is placed in a graphite crucible, and vacuum and infiltration treatment are sequentially performed to obtain a carbon ceramic friction plate. The temperature of the graphite crucible is 1500℃, and the temperature of the graphite crucible rises at a rate of 7℃ / min. The second mixed powder is composed of FeSi85 and Cu, and the mass ratio of FeSi85 to Cu is 90:10.

[0041] Example 4 has a similar structure to Example 3. The reduction of boron nitride reduces the surface opening, and the increase of phenolic resin makes the material more dense, so the mechanical properties are more excellent than those of Example 3.

[0042] Example 5 The preparation method of the pincer type carbon ceramic friction plate comprises the following steps: 40wt% phenolic resin, 10wt% titanium carbide, 15wt% silicon carbide, 20wt% graphite are first mixed for 1h, then 15wt% carbon fiber is added, and the mixture is uniformly mixed to obtain a powder.

[0043] Firstly, the demolding machine is evenly applied on the mold, then the powder is added, and the mold with the powder is put into the hot press for preheating treatment. The preheating treatment includes first preheating, second preheating and third preheating. The parameters of the first preheating are as follows: the hot press is heated to 80℃, the pressure is adjusted to 5Mpa for prepressing for 30s, and the process is repeated for 3 times. The parameters of the second preheating are as follows: the hot press is heated to 120℃, the pressure is adjusted to 10Mpa for prepressing for 30s, and the process is repeated for 5 times. The parameters of the third preheating are as follows: the hot press is heated to 180℃, the pressure is adjusted to 20Mpa for prepressing for 30s, and the process is repeated for 3 times. After the third preheating, the pressure is kept unchanged for 20min, and the green body is obtained after demolding.

[0044] The green body is placed in an oven and cured at 220℃ for 3h; the cured green body is placed in a cracking furnace, heated to 900℃ at a rate of 3℃ / min in a vacuum environment or by introducing inert gas, and kept for 1h for cracking; the cracked green body is placed in a heat treatment furnace, vacuumed first, then heated to 1800℃ at a rate of 5℃ / min, kept for 2h, and naturally cooled down with the furnace, finally obtaining a porous preform.

[0045] The porous preform is placed on the second mixed powder to obtain a composite structure; then the composite structure is placed in a graphite crucible, and vacuum and infiltration treatment are sequentially performed to obtain a carbon ceramic friction plate. The temperature of the graphite crucible is 1450℃, and the temperature of the graphite crucible rises at a rate of 5℃ / min. The second mixed powder is composed of FeSi85 and Cu, and the mass ratio of FeSi85 to Cu is 90:10.

[0046] The surface micro-morphology SEM photo of the carbon ceramic friction plate prepared in Example 5 is shown in Figure 3 As shown in the figure, due to the increase of the resin content and the absence of BN, the infiltration is more complete, and more SiC and FeSi2 phases generated by reaction are increased.

[0047] Comparing Example 5 with Example 3, it can be found that the increase of the resin leads to the increase of the density of the material after infiltration, and the increase of the SiC generated by reaction. The absence of BN makes the material denser, and significantly increases the friction coefficient.

[0048] Example 6 The preparation method of the present application is as follows: 25wt% phenolic resin, 5wt% titanium carbide, 5wt% boron nitride, 5wt% silicon carbide, 40wt% graphite are first mixed for 1h, then 20wt% carbon fiber is added, and the mixture is continuously mixed until uniform to obtain a first mixed powder.

[0049] Firstly, the release agent is evenly applied on the mold, then the first mixed powder is added, and the mold with the first mixed powder is put into the hot press for preheating treatment. The preheating treatment includes first preheating, second preheating and third preheating. The parameters of the first preheating are as follows: the hot press is heated to 80℃, the pressure is adjusted to 8Mpa for prepressing for 30s, and the process is repeated for 5 times. The parameters of the second preheating are as follows: the hot press is heated to 120℃, the pressure is adjusted to 13Mpa for prepressing for 30s, and the process is repeated for 5 times. The parameters of the third preheating are as follows: the hot press is heated to 180℃, the pressure is adjusted to 25Mpa for prepressing for 30s, and the process is repeated for 5 times. After the third preheating, the pressure is kept unchanged for 20min, and the green body is obtained after demolding.

[0050] The green body is placed in an oven and cured at 220℃ for 2h. The cured green body is placed in a cracking furnace, heated to 900℃ at a rate of 4℃ / min in a vacuum environment or by introducing inert gas, and kept for 1h for cracking. The cracked green body is placed in a heat treatment furnace, vacuumed first, then heated to 2000℃ at a rate of 5℃ / min, kept for 2h, and naturally cooled down with the furnace. Finally, a porous preform is obtained.

[0051] The porous preform is placed on the second mixed powder to obtain a composite structure. The composite structure is placed in a graphite crucible, and vacuum and infiltration treatment are sequentially performed to obtain a carbon ceramic friction plate. The temperature of the graphite crucible is 1500℃, and the temperature of the graphite crucible rises at a rate of 7℃ / min. The second mixed powder is composed of FeSi85 and Cu, and the mass ratio of FeSi85 to Cu is 90:10.

[0052] The surface micro-morphology SEM photo of the carbon ceramic friction plate prepared in Example 6 is shown in Figure 4 As shown in the figure, since the content of BN added is small and completely wrapped by graphite, it does not affect the infiltration effect, and the material surface is dense and defect-free.

[0053] Comparing Example 6 with Example 2, it can be found that appropriately increasing the content of resin and reducing the content of hard particles such as SiC can achieve almost the same friction performance, but the influence on the friction coefficient is mainly due to the reaction generated SiC.

[0054] Comparing Example 6 with Example 4, it can be found that increasing the amount of TiC and SiC can increase the friction coefficient to a certain extent, but at the same time, the increase of hard particles will lead to an increase in wear amount. The increase of graphite does not significantly reduce the friction coefficient.

[0055] Example 7 The carbon ceramic brake pad prepared in Examples 2-6 of the application was subjected to AK-Master friction and wear performance test analysis, specifically, the AKMaster program was used to evaluate the friction coefficient and wear rate, the entire AKMaster program included 255 braking, each braking formed a braking curve, the instantaneous friction coefficient peak difference of single braking was the difference between the highest point and the lowest point of the curve, the experiment was tested according to the American SAE-J2522 standard, and the test results are shown in Table 1. Among them, the carbon ceramic brake pad prepared from Example 4 was subjected to AK-Master friction and wear performance test analysis, 6 braking included in the AKMaster program were selected, and the braking curves of the 6 braking are shown in Figure 5 .

[0056] Table 1 Friction coefficient and wear test results

[0057] As can be seen from Table 1, compared with Example 6, the carbon ceramic friction pads prepared in Examples 3-4 of the application have suitable friction coefficients and lower wear amounts. Example 2 has a suitable friction coefficient but will wear the disc. Negative wear occurs because a transfer layer appears and the debris is pressed onto the disc surface under pressure. As can be seen from Table 1, Figure 5 , the peak difference of the instantaneous friction coefficient during single braking is large, the braking is unstable, and it is not suitable for ordinary passenger cars and is mainly used in racing cars. Since the wear on the disc is small, the service life of the disc is significantly improved, and the use conditions in extreme environments are met.

[0058] As can be seen from Example 3 and Example 6, as the amount of SiC added decreases, the number of SiC particles in the material decreases, resulting in a downward trend in the friction coefficient and the wear amount of the friction pad, but the change is limited.

[0059] As can be seen from Example 2 and Example 5, the increase in the content of the resin promotes the generation of SiC, thereby increasing the friction coefficient and enhancing the strength of the friction pad. High-strength friction pads can improve braking performance, but may exacerbate wear on the brake disc, while the wear amount of the friction pad itself is reduced. However, the lubrication and control of infiltration of BN can inhibit the excessive increase of the friction coefficient and reduce the overall wear amount, thereby optimizing the balance between the friction performance and wear resistance. BN is the abbreviation of boron nitride.

[0060] It has to be noted that the terms "first", "second", etc. as used in the description and the claims and above-mentioned figures of the application are used to distinguish between similar objects, not necessarily describing a particular sequential or chronological order. It is to be understood that the use of data "first", "second", etc., to distinguish between objects in the description and the claims is not anything more than notational and is merely intended to distinguish between two similar objects. It is further understood that data used in such a way can be interchangeable under appropriate circumstances, and embodiments of the present application described herein are capable of operation in other sequences than those explicitly described or illustrated herein. Furthermore, the terms "comprise" and "include" and variations thereof as used in the description and the claims and above-mentioned figures of the application are intended to cover both the respective case and the alternative case, i.e. to cover both the case of "comprising" and the case of "consisting of".

Claims

1. A method for preparing a clamp-type carbon-ceramic friction plate, characterized in that: The following steps are involved: Mixing phenolic resin, titanium carbide, boron nitride, silicon carbide, graphite and carbon fiber to obtain a first mixed powder; Add the first mixed powder into a mold and preheat it to obtain a blank; The green embryo is sequentially placed in an oven, a cracking furnace, and a heat treatment furnace for pretreatment to obtain a porous preform; The porous preform and the second mixed powder are vacuum infiltrated to obtain a carbon-ceramic friction plate.

2. The method for preparing the clamp-type carbon-ceramic friction plate according to claim 1, characterized in that: The first mixed powder comprises the following components by mass percentage: Phenolic resin 15-40%; titanium carbide 5-20%; boron nitride 5-10%; silicon carbide 5-20%; graphite 20-40%; carbon fiber 15-25%.

3. The method for preparing the clamp-type carbon-ceramic friction plate according to claim 1, characterized in that: The second mixed powder consists of FeSi85 and Cu; The mass ratio of FeSi85 to Cu is 90:

10.

4. The method for preparing the clamp-type carbon-ceramic friction plate according to claim 1, characterized in that: The preheating includes: a first preheating, a second preheating and a third preheating; The number of the first preheating is 3-5 times, the temperature of the first preheating is 80°C, the pressure of the first preheating is 5-10 MPa, and the preheating time is 30 seconds; The second preheating is performed 3-5 times; the second preheating temperature is 120°C, the second preheating pressure is 10-15 MPa, and the preheating time is 30 seconds; The third preheating is performed 3-5 times; the third preheating temperature is 180° C., the third preheating pressure is 20-30 MPa, and the preheating time is 30 seconds.

5. The method for preparing the clamp-type carbon-ceramic friction plate according to claim 1, characterized in that: The process of sequentially placing the green embryo into an oven, a cracking furnace, and a heat treatment furnace for pretreatment includes: The green blank is placed in an oven for curing. The solidified green blank is placed in a cracking furnace for cracking in a vacuum environment or by introducing an inert gas. The cracked green blank is placed in a heat treatment furnace.

6. The method for preparing the clamp-type carbon-ceramic friction plate according to claim 5, characterized in that: The oven temperature is 220°C and the curing time is 1-3 hours; The cracking temperature is 900°C and the time is 1 hour; The temperature of the heat treatment furnace is 1800-2400° C., and the time is 1-2 hours.

7. The method for preparing the clamp-type carbon-ceramic friction plate according to claim 6, characterized in that: The temperature of the cracking process is increased to 900° C. at a rate of 3-5° C. / min, and the temperature of the heat treatment furnace is increased to 1800-2400° C. at a rate of 5-10° C. / min.

8. The method for preparing the clamp-type carbon-ceramic friction plate according to claim 1, characterized in that: The method of vacuum infiltration treating the porous preform and the second mixed powder to obtain the carbon-ceramic friction plate comprises: Laying the porous preform on the second mixed powder to obtain a composite structure; The composite structure is placed in a graphite crucible, and vacuum and infiltration treatments are sequentially performed to obtain a carbon-ceramic friction plate, wherein the temperature of the graphite crucible is 1400-1600°C.

9. The method for preparing the clamp-type carbon-ceramic friction plate according to claim 8, characterized in that: The graphite crucible is heated to 1400-1600° C. at a rate of 5-10° C. / min.

10. A carbon-ceramic friction plate prepared by the preparation method according to any one of claims 1 to 9.

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