A method for preparing and applying a high-temperature stable resin-based friction material

Abstract

This invention discloses a method for preparing and applying a high-temperature stable resin-based friction material, relating to the field of automotive friction materials technology. The preparation method includes the following steps: mixing thermosetting resin binder, reinforcing fibers, metal fillers, friction modifiers, ceramic abrasives, and damping agents in a high-speed mixer to obtain a uniform mixture; placing the mixture in a mold and hot-pressing it to obtain friction material A; subjecting friction material A to post-curing heat treatment to completely cure the thermosetting resin binder to obtain friction material B; machining friction material B; and subjecting the machined friction material B to a high-temperature surface ablation treatment to obtain a high-temperature stable resin-based friction material. The friction material prepared by this invention has the following effects: significantly improved high-temperature stability, enhanced friction coefficient stability, significantly reduced wear on aluminum-ceramic brake discs, and excellent initial friction performance.

Description

Technical Field

[0001] This invention belongs to the field of automotive friction materials technology, and particularly relates to a method for preparing and applying a high-temperature stable resin-based friction material. Background Technology

[0002] With the rapid development of new energy vehicles and high-end passenger cars, lightweighting has become a key direction for improving driving range, acceleration performance, and handling. Aluminum-based ceramic composite brake discs utilize a structure with uniformly distributed silicon carbide (SiC) particles within an aluminum alloy matrix. This retains the high hardness, high-temperature resistance, and wear resistance of ceramics while reducing the weight of the brake disc by approximately 30% to 50% compared to traditional gray cast iron discs. This significantly reduces the unsprung mass of the vehicle and has gradually become a preferred solution for high-end configurations in new energy vehicles. Furthermore, aluminum-ceramic discs also offer advantages such as water resistance, aesthetic appeal, and superior thermal conductivity compared to cast iron.

[0003] However, the hardness of aluminum-ceramic brake discs is typically only HB100~150, far lower than the HB200~250 of traditional cast iron discs. This lower hardness results in extremely stringent requirements for the matching of friction materials to aluminum-ceramic discs: if traditional resin-based friction pads designed for cast iron discs are used directly, the following prominent problems will occur:

[0004] 1. The overall coefficient of friction is relatively low, resulting in insufficient braking force, especially under medium braking pressure, which affects braking safety;

[0005] 2. During continuous braking at high temperatures, thermal fade is severe, the coefficient of friction drops sharply (it can drop to below 0.20), and recovery performance is poor;

[0006] 3. The wear rate of the friction pads is accelerated, and at the same time, it causes greater wear on the aluminum ceramic disc, which can easily lead to scratches on the disc surface, protrusion of ceramic particles or instability of the transfer film, resulting in brake vibration and increased noise.

[0007] 4. During the initial break-in period, the frictional performance is unstable, and the weak bonding layer on the surface is prone to falling off, affecting the reliability of the first braking.

[0008] The existing resin-based friction material preparation process mainly includes raw material mixing, hot pressing, post-curing, and machining. Although it is relatively mature, it generally lacks special optimization measures for the low hardness characteristics of aluminum ceramic discs. The friction pad surface after hot pressing still has a weak bonding layer and residual stress. It is prone to peeling or dust in the early stage of high-temperature use, and the initial friction coefficient fluctuates greatly, making it difficult to quickly form a stable transfer film.

[0009] Therefore, there is an urgent need to develop a method for preparing a high-temperature stable resin-based friction material specifically for matching aluminum-ceramic brake discs, so that it can recover quickly after high-temperature degradation, cause low wear on the aluminum-ceramic disc, and have good initial friction performance and braking safety. Summary of the Invention

[0010] To address the aforementioned technical problems, this invention provides a method for preparing and applying a high-temperature stable resin-based friction material. The specific technical solution is as follows:

[0011] A method for preparing a high-temperature stable resin-based friction material includes the following steps:

[0012] S1. Weigh the thermosetting resin binder, reinforcing fiber, metal filler, friction modifier, ceramic abrasive, and damping agent in a mass ratio of (3~8):(10~25):(21~55):(5~15):(8~25):(8~23), and then put them into a high-speed mixer to mix evenly to obtain a mixture.

[0013] S2. Place the mixture in a mold and hot press it to obtain friction material A;

[0014] S3. The friction material A is subjected to post-curing heat treatment to completely cure the thermosetting resin adhesive and obtain friction material B;

[0015] S4. The friction material B is machined;

[0016] S5. The machined friction material B is subjected to high-temperature surface short-time ablation treatment to obtain a high-temperature stable resin-based friction material.

[0017] Preferably:

[0018] The thermosetting resin adhesive is selected from at least one of phenolic resin and phenolic modified resin;

[0019] The reinforcing fibers include steel fibers and aramid pulp;

[0020] The metal filler includes reduced iron powder, copper powder, brass powder, and tin-copper alloy powder;

[0021] The friction modifier includes antimony trisulfide, molybdenum disulfide solid lubricants, and zinc oxide powder;

[0022] The ceramic abrasive particles include calcined alumina and silicon carbide;

[0023] The damping agent includes potassium magnesium titanate flakes, sericite, and vermiculite.

[0024] Preferably:

[0025] The metal filler also includes low-melting-point tin-based alloy powder;

[0026] The molybdenum disulfide solid lubricant is selected from carbon-coated modified molybdenum disulfide.

[0027] Preferably, the low-melting-point tin-based alloy powder is a Sn-Zn alloy powder.

[0028] Preferably, the thermosetting resin binder is a boron-modified phenolic resin.

[0029] Preferably:

[0030] In step S1, the mixing time is 10~20 min, the spindle speed of the high-speed mixer is 100~200 r / min, and the speed of the flying knife is 2000~3500 r / min;

[0031] In step S2, the hot pressing pressure is 300~500 kg / cm². 2 The molding temperature is 140~170℃, the holding time is 200~500s, and 4~10 venting operations are performed during the process, with each venting operation lasting no more than 5s.

[0032] In step S3, the post-curing heat treatment involves heating to 180-220°C at a rate of 2-5°C / min, holding at that temperature for 4-12 hours, and then allowing it to cool naturally to room temperature.

[0033] In step S4, the machining process includes surface grinding;

[0034] In step S5, the high-temperature surface short-time ablation treatment temperature is 500~650℃, and the treatment time is 2~6min.

[0035] Preferably, the carbon-coated modified molybdenum disulfide is prepared by the following steps:

[0036] S01. Disperse molybdenum disulfide powder and carbon source in deionized water at a mass ratio of 1:(0.5~2), and ultrasonically disperse for 30~60 min to obtain a uniform suspension;

[0037] S02. Transfer the suspension to a hydrothermal reactor and react at 180~220℃ for 6~12h;

[0038] S03. After the reaction is complete, filter, wash and dry at 80~100℃ to obtain carbon-coated precursor;

[0039] S04. The carbon-coated precursor is heat-treated at 500~700℃ for 1~3h under an inert atmosphere to obtain the carbon-coated modified molybdenum disulfide.

[0040] Preferably, the boron-modified phenolic resin is prepared by the following steps:

[0041] S001. Weigh phenol, formaldehyde, and boric acid in a molar ratio of (1~1.2):(1.2~1.8):(0.1~0.4);

[0042] S002. Add phenol to the reaction vessel, add alkaline catalyst, stir and heat to 60~80℃, wherein the molar ratio of alkaline catalyst to phenol is 0.01~0.1;

[0043] S003. Slowly add a portion of formaldehyde, with the added formaldehyde accounting for 60-80% of the total amount, and control the temperature at 80-95℃, and keep the reaction at this temperature for 1-2 hours;

[0044] S004. Cool down to 70~80℃, add boric acid, and continue to heat to 100~120℃, and keep the temperature for 1~2 hours.

[0045] S005. Add the remaining formaldehyde, heat to 92~110℃, and maintain the temperature until the viscosity reaches 50~100 mPa·s;

[0046] S006. Dehydration under reduced pressure, controlling the vacuum degree to 0.04~0.08 MPa, and gradually increasing the temperature to 140~160℃;

[0047] S007. When the resin becomes transparent or semi-transparent viscous, cool it to below 40~60℃ and discharge it to obtain the boron-modified phenolic resin.

[0048] The present invention also provides an application of a high-temperature stable resin-based friction material prepared by any of the above methods, wherein the high-temperature stable resin-based friction material is applied to a friction pad.

[0049] Preferably, the friction pad is used in a friction pair that matches an aluminum-based ceramic composite brake disc.

[0050] The preparation method provided by this invention has the following beneficial effects:

[0051] 1. Significantly improved high-temperature stability: Under continuous high-temperature braking conditions, the rate of friction coefficient decay is significantly reduced, and the recovery performance after thermal decay is better, effectively mitigating the risk of high-temperature failure of traditional resin-based friction pads when matched with aluminum ceramic discs;

[0052] 2. Improved stability of friction coefficient: The friction coefficient fluctuates less over a wide temperature range and under different braking pressures, resulting in better braking linearity and meeting the braking requirements of passenger vehicles, especially new energy vehicles.

[0053] 3. Significantly reduced wear on aluminum-ceramic brake discs: The transfer film is more stable, and initial erosion is reduced after surface optimization, resulting in less wear on the aluminum-ceramic disc body and avoiding excessive scratches on the disc surface and protrusion of ceramic particles;

[0054] 4. Excellent initial friction performance: After short-term ablation treatment of the surface at high temperature, the break-in period of the friction pads is greatly shortened, and a stable transfer film can be quickly established during the first braking, reducing noise, vibration and dust in the initial stage;

[0055] 5. The preparation process is mature, the parameters are controllable, and it is suitable for industrial production. It does not require complex equipment or harmful additives, and it has good overall environmental protection and economic benefits. Attached Figure Description

[0056] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0057] Figure 1 This is a photograph of the appearance of the high-temperature stable resin-based friction material prepared in Example 1 of the present invention in its unused state;

[0058] Figure 2 The photos show the wear appearance of the high-temperature stable resin-based friction material prepared in Example 1 of the present invention after bench testing. Detailed Implementation

[0059] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be described in detail below. The description in this part is only exemplary and explanatory, and should not be used to limit the scope of protection of the present invention in any way.

[0060] This embodiment provides a method for preparing a high-temperature stable resin-based friction material, including the following steps:

[0061] S1. Weigh the thermosetting resin binder, reinforcing fiber, metal filler, friction modifier, ceramic abrasive, and damping agent in a mass ratio of (3~8):(10~25):(21~55):(5~15):(8~25):(8~23), and then put them into a high-speed mixer to mix evenly to obtain a mixture.

[0062] S2. Place the mixture in a mold and hot press it to obtain friction material A.

[0063] S3. After the friction material A is subjected to post-curing heat treatment, the friction material B is obtained after the thermosetting resin adhesive is completely cured.

[0064] S4. Machining of friction material B.

[0065] S5. The machined friction material B is subjected to high-temperature surface short-time ablation treatment to obtain a high-temperature stable resin-based friction material.

[0066] Thermosetting resin binder provides a high-temperature bonding base, reinforcing fibers impart mechanical strength and toughness, metal fillers improve thermal conductivity and friction interface strength, friction modifiers regulate the stability of the friction coefficient, ceramic abrasives provide cutting friction enhancement, and damping agents reduce vibration and noise. These components work together during friction to form a third-body transfer film covering the surface of the aluminum-ceramic brake disc. This transfer film effectively reduces direct hard contact between the friction pads and the aluminum-ceramic disc substrate, alleviating the wear problem caused by the low hardness of the aluminum-ceramic disc, while maintaining the relative stability of the friction coefficient. This improves upon the phenomenon of easy damage to the transfer film and a sharp decline in the friction coefficient at high temperatures in traditional solutions.

[0067] The surface of the friction material after hot pressing (step S2) and post-curing (step S3) typically retains a resin-rich layer, weakly bonded particles, microcracks, and residual stress introduced during the molding process. These surface defects can lead to large fluctuations in the friction coefficient during the initial braking stage, a long break-in period, excessive dust generation, and even localized peeling, causing early scratches on the aluminum ceramic disc. Step S5 involves a short-term (2-6 min) ablation treatment at 500-650℃, controlled by a high-temperature inert / micro-oxidizing atmosphere.

[0068] 1. Selectively removes weakly bound layers and low-molecular-weight volatiles from the surface;

[0069] 2. Promotes mild carbonization of the resin surface, forming a denser and more stable surface protective layer;

[0070] 3. Optimize the surface microstructure and chemical activity to increase surface energy, so that the transfer film can be quickly and uniformly attached to the aluminum ceramic disc surface during the first braking.

[0071] This step significantly shortens the break-in period, improves the stability of initial friction performance, and reduces the risk of early corrosion of the aluminum ceramic disc.

[0072] Specifically, step S1, high-speed mixing, ensures uniform dispersion of all components without agglomeration; step S2, hot pressing, achieves dense molding and initial cross-linking; step S3, post-curing, fully cures the resin and releases internal stress; step S4, machining, ensures dimensional accuracy and flatness; and step S5, surface ablation, serves as the final optimization step, further improving surface quality. The entire process works synergistically, resulting in friction materials that exhibit better thermal stability, consistent coefficient of friction, and good compatibility with aluminum ceramic discs over a wide temperature range.

[0073] Based on the above mechanism, the preparation method of this embodiment can significantly improve problems such as high-temperature thermal decay, initial frictional instability, and excessive wear of aluminum ceramic discs without relying on specific high-performance components.

[0074] Compared with the prior art, the preparation method provided in this embodiment has the following beneficial effects:

[0075] 1. Significantly improved high-temperature stability: Under continuous high-temperature braking conditions, the rate of friction coefficient decay is significantly reduced, and the recovery performance after thermal decay is better, effectively mitigating the risk of high-temperature failure of traditional resin-based friction pads when matched with aluminum ceramic discs;

[0076] 2. Improved stability of friction coefficient: The friction coefficient fluctuates less over a wide temperature range and under different braking pressures, resulting in better braking linearity and meeting the braking requirements of passenger vehicles, especially new energy vehicles.

[0077] 3. Significantly reduced wear on aluminum-ceramic brake discs: The transfer film is more stable, and initial erosion is reduced after surface optimization, resulting in less wear on the aluminum-ceramic disc body and avoiding excessive scratches on the disc surface and protrusion of ceramic particles;

[0078] 4. Excellent initial friction performance: After short-term ablation treatment of the surface at high temperature, the break-in period of the friction pads is greatly shortened, and a stable transfer film can be quickly established during the first braking, reducing noise, vibration and dust in the initial stage;

[0079] 5. The preparation process is mature, the parameters are controllable, and it is suitable for industrial production. It does not require complex equipment or harmful additives, and it has good overall environmental protection and economic benefits.

[0080] Furthermore:

[0081] The thermosetting resin adhesive is selected from at least one of phenolic resin and phenolic modified resin.

[0082] Reinforcing fibers include steel fibers and aramid pulp, and may further include ceramic fibers.

[0083] Metal fillers include reduced iron powder, copper powder, brass powder, and tin-copper alloy powder.

[0084] Friction modifiers include antimony trisulfide, molybdenum disulfide solid lubricants, and zinc oxide powder.

[0085] Ceramic abrasives include calcined alumina and silicon carbide.

[0086] Damping agents include potassium magnesium titanate flakes, sericite, and vermiculite.

[0087] Thermosetting resin binders provide high-temperature bonding strength and a molding base; reinforcing fibers enhance mechanical strength, toughness, and fatigue resistance, reducing crack propagation; metal fillers improve thermal conductivity, increase friction, and enhance the stability of the friction interface; friction modifiers regulate the stability of the coefficient of friction, providing a balance between lubrication and friction enhancement, and reducing high-temperature degradation; ceramic abrasives provide cutting friction enhancement, ensuring "engagement force" and coefficient of friction; damping agents reduce vibration and noise, improving comfort; these components work synergistically to give the friction material basic stability in the coefficient of friction, wear resistance, and thermal stability, making it suitable for general braking scenarios.

[0088] Further, the preferred components are 4-6 parts phenolic resin, 8-15 parts steel fiber, 2-5 parts aramid pulp, 2-5 parts ceramic fiber (alumina fiber and / or potassium titanate whiskers), 10-20 parts reduced iron powder, 5-12 parts copper powder, 5-12 parts brass powder, 1-8 parts tin-copper alloy powder, 2-6 parts antimony trisulfide, 2-6 parts molybdenum disulfide solid lubricant, 1-3 parts zinc oxide powder, 4-10 parts calcined alumina, 4-10 parts silicon carbide, 6-12 parts potassium magnesium titanate flakes, 3-6 parts sericite, 2-5 parts vermiculite, and may also include 2-6 parts magnesium oxide. All metal powders are preferably <75μm in size to ensure uniform dispersion, and ceramic abrasive particles are preferably <20μm in size. All large-particle raw materials must be pre-ground into fine powder before use to avoid agglomeration and improve dispersion uniformity and friction interface stability.

[0089] Furthermore:

[0090] Metal fillers also include low-melting-point tin-based alloy powder.

[0091] Molybdenum disulfide solid lubricants are selected from carbon-coated modified molybdenum disulfide.

[0092] Among them, 1 to 3 parts of low-melting-point tin-based alloy powder are preferred. The low-melting-point tin-based alloy powder, carbon-coated modified molybdenum disulfide, and zinc oxide powder, together with the aforementioned basic components, form the core mechanism of the temperature gradient adaptive composite transfer film:

[0093] 1. Low temperature stage (<200℃): Low melting point tin-based alloy powder (melting point 180~230℃) melts slightly under frictional heat, forming a thin sacrificial lubricating film, reducing early wear and scratches on the aluminum ceramic disc.

[0094] 2. Medium temperature stage (200~400℃): Zinc oxide powder generates a soft oxide film with low shear strength in situ at the friction interface, providing a moderate balance between friction enhancement and lubrication, and maintaining a stable coefficient of friction.

[0095] 3. High temperature stage (>400℃): Carbon-coated modified molybdenum disulfide maintains solid lubrication performance with its dense carbon layer (anti-oxidation protection), forming a long-lasting high-temperature stable transfer film to avoid oxidation failure and thermal degradation.

[0096] This three-level adaptive mechanism significantly improves the temperature stability of the friction coefficient, the thermal decay recovery speed, and the low-wear protection of the aluminum ceramic disc.

[0097] Furthermore, the low-melting-point tin-based alloy powder is a Sn-Zn alloy powder (Sn 70~95wt%, Zn 5~30wt%, melting point 180~230℃). The Sn-Zn alloy forms a mild lubricating layer during the initial stage of friction with minimal erosion of the aluminum substrate. In synergy with carbon-coated MoS2 and ZnO, it further optimizes the uniformity and adhesion of the low-temperature and medium-temperature transfer film, improving overall compatibility.

[0098] Furthermore, the thermosetting resin binder is a boron-modified phenolic resin (boron content 2-8 wt% (B), thermal decomposition initiation temperature ≥450℃, nitrogen char residue ≥65% at 800℃). Boron introduces high-energy BO bonds, improving the resin's crosslinking degree and thermal stability. At high temperatures, the resin is less prone to premature decomposition, and the carbonized layer is denser, synergizing with the aforementioned adaptive transfer film.

[0099] 1. Improved resin heat resistance, no adhesive failure at high temperatures, and more durable and stable transfer film.

[0100] 2. High carbon residue rate, denser high-temperature friction layer, reducing scratches and dust on aluminum ceramic discs.

[0101] The overall system achieves multi-dimensional synergy between "resin body heat resistance + multi-level transfer film", significantly improving high-temperature degradation recovery and disc wear.

[0102] Furthermore:

[0103] In step S1, the mixing time is 10~20 min, the spindle speed of the high-speed mixer is 100~200 r / min, and the speed of the flying knife is 2000~3500 r / min.

[0104] In step S2, the hot pressing pressure is 300~500 kg / cm². 2 The molding temperature is 140~170℃, the holding time is 200~500s, and 4~10 venting operations are performed during the process, with each venting operation lasting no more than 5s.

[0105] In step S3, the post-curing heat treatment involves heating to 180-220°C at a rate of 2-5°C / min, holding at that temperature for 4-12 hours, and then allowing it to cool naturally to room temperature.

[0106] In step S4, the machining process includes surface grinding.

[0107] In step S5, the high-temperature surface short-time ablation treatment temperature is 500~650℃, and the treatment time is 2~6min.

[0108] Furthermore, carbon-coated modified molybdenum disulfide is prepared through the following steps:

[0109] S01. Disperse molybdenum disulfide powder and carbon source in deionized water at a mass ratio of 1:(0.5~2), and ultrasonically disperse for 30~60 min to obtain a uniform suspension.

[0110] S02. Transfer the suspension to a hydrothermal reactor and react at 180~220℃ for 6~12h.

[0111] S03. After the reaction is complete, filter, wash and dry at 80~100℃ to obtain carbon-coated precursor.

[0112] S04. The carbon-coated precursor is heat-treated at 500~700℃ for 1~3h under an inert atmosphere to obtain carbon-coated modified molybdenum disulfide.

[0113] Among them, carbon-coated modified molybdenum disulfide was prepared by hydrothermal + carbonization process, with a carbon layer thickness of 5~20nm, which significantly improved the oxidation resistance of MoS2, enabling it to maintain stable lubrication at >400℃. The molybdenum disulfide powder particle size was <5μm to ensure uniform dispersion; the carbon source was selected from glucose or sucrose (mass ratio 1:0.5~2); the inert atmosphere was nitrogen or argon; the hydrothermal temperature was 180~220℃, and the time was 6~12h; the carbonization temperature was 500~700℃, and the time was 1~3h.

[0114] This modified MoS2 provides durable solid lubrication in high-temperature transfer films, forming a complete gradient with Sn-Zn micro-melt and ZnO in-situ films.

[0115] Furthermore, the boron-modified phenolic resin is prepared through the following steps:

[0116] S001. Weigh phenol, formaldehyde and boric acid in a molar ratio of (1~1.2):(1.2~1.8):(0.1~0.4).

[0117] S002. Add phenol to the reaction vessel, add alkaline catalyst, stir and heat to 60~80℃, wherein the molar ratio of alkaline catalyst to phenol is 0.01~0.1.

[0118] S003. Slowly add a portion of formaldehyde, with the added formaldehyde accounting for 60-80% of the total amount, and control the temperature at 80-95℃, keeping the reaction at this temperature for 1-2 hours.

[0119] S004. Cool down to 70~80℃, add boric acid, and continue to heat to 100~120℃, and keep the temperature for 1~2 hours.

[0120] S005. Add the remaining formaldehyde, heat to 92~110℃, and maintain the temperature until the viscosity reaches 50~100 mPa·s.

[0121] S006. Dehydration under reduced pressure, controlling the vacuum degree to 0.04~0.08 MPa, and gradually increasing the temperature to 140~160℃.

[0122] S007. Once the resin is transparent or semi-transparent viscous, cool it to below 40~60℃ and discharge it to obtain boron-modified phenolic resin.

[0123] The preferred molar ratio of phenol:formaldehyde:boric acid is 1:(1.4~1.6):(0.2~0.35); the alkaline catalyst is sodium hydroxide or potassium hydroxide (molar ratio with phenol 0.01~0.1); the boron content (calculated as B) is 2~8wt%; the thermal decomposition initiation temperature is ≥450℃; and the nitrogen residual carbon rate at 800℃ is ≥65%.

[0124] This embodiment also provides an application of the high-temperature stable resin-based friction material prepared by any of the above preparation methods, wherein the high-temperature stable resin-based friction material is applied to friction pads.

[0125] Furthermore, friction pads are used in friction pairs that are matched with aluminum-based ceramic composite brake discs.

[0126] Beneficially, applying the prepared friction material to friction pads, especially to friction pairs matched with aluminum-based ceramic composite brake discs, can achieve a stable friction coefficient over a wide temperature range and low thermal decay; reduce wear on the aluminum ceramic disc and avoid scratches or ceramic particle protrusion on the disc surface; provide excellent initial performance, a short break-in period, low noise / vibration, and less dust; and overall meet the lightweight and high-performance braking requirements of aluminum ceramic discs for new energy vehicles, while also being environmentally friendly.

[0127] Specific embodiments are provided below. These embodiments are intended to enable those skilled in the art to more fully understand the present invention, but do not limit the present invention in any way.

[0128] Example 1

[0129] Step 1: Raw Material Preparation

[0130] Steel fibers, reduced iron powder, calcined alumina, silicon carbide, and potassium magnesium titanate flakes were ball-milled for 2 hours using a planetary ball mill at a speed of 400 r / min and a ball-to-material ratio of 10:1.

[0131] Weigh the following: 250.0 g of phenolic resin (type 2123, polymerization rate 40 s), 600.0 g of steel fiber, 150.0 g of aramid pulp, 500.0 g of reduced iron powder, 400.0 g of copper powder, 300.0 g of brass powder, 250.0 g of tin-copper alloy powder (Sn 10 wt%), 250.0 g of antimony trisulfide, 250.0 g of molybdenum disulfide (particle size <5 μm), 100.0 g of zinc oxide powder, 350.0 g of calcined alumina, 300.0 g of silicon carbide, 450.0 g of potassium magnesium titanate flakes, 350.0 g of sericite, and 330.0 g of vermiculite.

[0132] Step 2: Mixing

[0133] Using a high-speed plow mixer with a spindle speed of 140 r / min and a cutter speed of 3000 r / min, resin, fiber, metal filler, friction modifier, ceramic abrasive, and damping agent were added sequentially in three batches, stirring for 3-5 minutes each time to prevent agglomeration. The mixture was uniform in color, without obvious agglomeration, and had good flowability.

[0134] Step 3: Hot pressing

[0135] A flat vulcanizing machine was used, employing a standard brake pad mold (friction block size 150 mm × 60 mm × 2 mm), with a pressing pressure of 420 kg / cm². 2 The hot pressing temperature was 155℃, the holding time was 8 s / cycle, and the venting time was 3 s / cycle, for a total of 6 cycles. Friction material A was obtained.

[0136] Step 4: Post-curing heat treatment

[0137] Using an electric heating drying oven, the temperature was raised from room temperature to 205℃ at a rate of 3.5℃ / min, and held for 8 hours. The oven was then allowed to cool naturally to room temperature (approximately 12 hours) to obtain friction material B. The resin was completely cured and showed no obvious cracks.

[0138] Step 5: Machining

[0139] Use a surface grinder (accuracy 0.01 mm) to perform double-sided surface grinding, ensuring parallelism ≤0.02 mm and flatness ≤0.03 mm; chamfering is then performed.

[0140] Step Six: High-Temperature Surface Short-Time Ablation Treatment

[0141] A box-type resistance furnace was used at a temperature of 580℃ for 3.5 minutes. The first 1.5 minutes were under nitrogen protection (flow rate 2 L / min), followed by 2 minutes under a slightly oxidizing atmosphere (nitrogen + air 1:0.1) to remove the weak surface layer, resulting in a uniform gray-black protective layer.

[0142] Step 7: Performance Testing

[0143] The testing equipment used was an inertial braking dynamometer, and the mating disc was an aluminum-based ceramic composite brake disc. The testing methods were: SAE J2522-2003 full-series test and AMS thermal decay series test. The test data are shown in Tables 1-1 and 1-2 below:

[0144]

[0145]

[0146] In this embodiment, the SAE J2522-2003 test results show that the nominal coefficient of friction is 0.40, and the pressure sensitivity is low (0.36~0.38), indicating good linearity of braking force. The μ value in the 500℃ high-temperature test is 0.26, the lowest coefficient of friction is 0.26, and the recovery value after thermal degradation is as high as 0.41~0.42, indicating small thermal degradation amplitude and rapid recovery. The wear amount of the inner plate is 0.41 mm and the outer plate is 0.31 mm, with low overall wear, indicating good matching with the aluminum ceramic disc. AMS testing further verified the thermal degradation performance, with a lowest coefficient of friction of 0.23, meeting the passenger car standard requirements (>0.20). The μ value fluctuations in each segment are small, showing stable high-temperature thermal degradation resistance.

[0147] Example 2

[0148] Step 1: Raw Material Preparation

[0149] Steel fibers, reduced iron powder, calcined alumina, silicon carbide, and potassium magnesium titanate flakes were ball-milled for 2 hours using a planetary ball mill at a speed of 400 r / min and a ball-to-material ratio of 10:1.

[0150] Weigh the following: 250.0 g of phenolic resin (type 2123, polymerization rate 40 s), 500.0 g of steel fiber, 150.0 g of aramid pulp, 600.0 g of reduced iron powder, 350.0 g of copper powder, 350.0 g of brass powder, 300.0 g of tin-copper alloy powder (Sn 10 wt%), 300.0 g of antimony trisulfide, 300.0 g of molybdenum disulfide (particle size <5 μm), 100.0 g of zinc oxide powder, 400.0 g of calcined alumina, 250.0 g of silicon carbide, 450.0 g of potassium magnesium titanate flakes, 400.0 g of sericite, and 330.0 g of vermiculite.

[0151] Step 2: Mixing

[0152] Using a high-speed plow mixer with a spindle speed of 140 r / min and a cutter speed of 3000 r / min, resin, fiber, metal filler, friction modifier, ceramic abrasive, and damping agent were added sequentially in three batches, stirring for 3-5 minutes each time to prevent agglomeration. The mixture was uniform in color, without obvious agglomeration, and had good flowability.

[0153] Step 3: Hot pressing

[0154] A flat vulcanizing machine was used, employing standard brake pad molds (friction block dimensions 150 mm × 60 mm × 12 mm), with a pressing pressure of 420 kg / cm². 2 The hot pressing temperature was 155℃, the holding time was 8 s / cycle, and the venting time was 3 s / cycle, for a total of 6 cycles. Friction material A was obtained.

[0155] Step 4: Post-curing heat treatment

[0156] Using an electric heating drying oven, the temperature was raised from room temperature to 205℃ at a rate of 3.5℃ / min, and held for 8 hours. The oven was then allowed to cool naturally to room temperature (approximately 12 hours) to obtain friction material B. The resin was completely cured and showed no obvious cracks.

[0157] Step 5: Machining

[0158] Use a surface grinder (accuracy 0.01 mm) to perform double-sided surface grinding, ensuring parallelism ≤0.02 mm and flatness ≤0.03 mm; chamfering is then performed.

[0159] Step Six: High-Temperature Surface Short-Time Ablation Treatment

[0160] A box-type resistance furnace was used at a temperature of 580℃ for 3.5 minutes. The first 1.5 minutes were under nitrogen protection (flow rate 2 L / min), followed by 2 minutes under a slightly oxidizing atmosphere (nitrogen + air 1:0.1) to remove the weak surface layer, resulting in a uniform gray-black protective layer.

[0161] Step 7: Performance Testing

[0162] The testing equipment used was an inertial braking dynamometer, and the mating disc was an aluminum-based ceramic composite brake disc. The testing methods were: SAE J2522-2003 full-series test and AMS thermal decay series test. The test data are shown in Tables 2-1 and 2-2 below:

[0163]

[0164]

[0165] In this embodiment, the SAE J2522-2003 test showed that the nominal coefficient of friction was 0.37, the pressure sensitivity remained in the range of 0.36~0.38, and the braking force was linearly stable; the μ value in the high temperature 500℃ test was 0.28, the minimum coefficient of friction was 0.28, and the recovery value after decay was 0.36~0.37, indicating a small thermal decay range and good recovery performance; the wear amount of the inner piece was 0.38 mm and the outer piece was 0.33 mm, indicating excellent overall wear control.

[0166] Example 3

[0167] Step 1: Preparation of carbon-coated modified molybdenum disulfide

[0168] 125.0 g of molybdenum disulfide powder and 125.0 g of glucose were added to 1.5 L of deionized water and ultrasonically dispersed for 45 min using an ultrasonic disperser (power 500 W) to obtain a uniform suspension.

[0169] The suspension was transferred to a polytetrafluoroethylene-lined hydrothermal reactor, sealed, and placed in an electric heating drying oven. The temperature was raised to 200°C, and the reaction was carried out for 10 hours.

[0170] After the reaction was completed, the mixture was naturally cooled to room temperature, filtered, washed three times with deionized water, and dried under vacuum at 80°C for 12 h to obtain the carbon-coated precursor.

[0171] The dried precursor was placed in a tube furnace, protected with nitrogen (flow rate 0.5 L / min), and heated to 600℃ at a rate of 5℃ / min, held for 2 h, and then carbonized and coated.

[0172] The product was cooled to room temperature in the furnace to obtain carbon-coated modified molybdenum disulfide. The finished product was sealed and stored for later use.

[0173] Step 2: Raw Material Preparation

[0174] Steel fibers, reduced iron powder, calcined alumina, silicon carbide, and potassium magnesium titanate flakes were ball-milled for 2 hours using a planetary ball mill at a speed of 400 r / min and a ball-to-material ratio of 10:1.

[0175] Weigh the following: 250.0 g of phenolic resin (type 2123, polymerization rate 40 s), 600.0 g of steel fiber, 150.0 g of aramid pulp, 450.0 g of reduced iron powder, 400.0 g of copper powder, 300.0 g of brass powder, 250.0 g of tin-copper alloy powder (Sn 10 wt%), 125.0 g of Sn-Zn alloy powder (Sn 85 wt%, Zn 15 wt%), 250.0 g of antimony trisulfide, 175.0 g of carbon-coated modified molybdenum disulfide, 150.0 g of zinc oxide powder, 350.0 g of calcined alumina, 300.0 g of silicon carbide, 450.0 g of potassium magnesium titanate flakes, 350.0 g of sericite, and 300.0 g of vermiculite.

[0176] Step 3: Mixing

[0177] Using a high-speed plow mixer with a spindle speed of 140 r / min and a cutter speed of 3000 r / min, resin, fiber, metal filler (including Sn-Zn alloy powder), friction modifier (containing carbon-coated modified molybdenum disulfide), ceramic abrasive particles, and damping agent were added sequentially in three batches, stirring for 3-5 minutes each time to prevent agglomeration. The mixture was uniform in color, without obvious agglomeration, and had good flowability.

[0178] Step 4: Hot pressing

[0179] A flat vulcanizing machine was used, employing standard brake pad molds (friction block dimensions 150 mm × 60 mm × 12 mm), with a pressing pressure of 420 kg / cm². 2 The hot pressing temperature was 155℃, the holding time was 8 s / cycle, and the venting time was 3 s / cycle, for a total of 6 cycles. Friction material A was obtained.

[0180] Step 5: Post-curing heat treatment

[0181] Using an electric heating drying oven, the temperature was raised from room temperature to 205℃ at a rate of 3.5℃ / min, and held for 8 hours. The oven was then allowed to cool naturally to room temperature (approximately 12 hours) to obtain friction material B. The resin was completely cured and showed no obvious cracks.

[0182] Step Six: Machining

[0183] Use a surface grinder (accuracy 0.01 mm) to perform double-sided surface grinding, ensuring parallelism ≤0.02 mm and flatness ≤0.03 mm; chamfering is then performed.

[0184] Step 7: High-temperature surface short-time ablation treatment

[0185] A box-type resistance furnace was used at a temperature of 580℃ for 3.5 minutes. The first 1.5 minutes were under nitrogen protection (flow rate 2 L / min), followed by 2 minutes under a slightly oxidizing atmosphere (nitrogen + air 1:0.1) to remove the weak surface layer, resulting in a uniform gray-black protective layer.

[0186] Step 8: Performance Testing

[0187] The testing equipment used was an inertial braking dynamometer, and the mating disc was an aluminum-based ceramic composite brake disc. The testing methods were: SAE J2522-2003 full-series test and AMS thermal decay series test. The test data are shown in Tables 3-1 and 3-2 below:

[0188]

[0189]

[0190] In this embodiment, the SAE J2522-2003 test results show that the nominal coefficient of friction is increased to 0.42, the pressure sensitivity remains in the range of 0.39~0.40, and the linearity of braking force is further optimized; the μ value in the high-temperature 500℃ test is 0.29, the lowest coefficient of friction is 0.29, and the recovery value after fading reaches 0.43~0.44, indicating a significant reduction in the thermal fading amplitude and a faster recovery speed; the wear amount of the inner disc is 0.36 mm and the outer disc is 0.27 mm, which is about 10~15% lower than that in Examples 1 and 2, indicating a further reduction in the wear degree of the aluminum-based ceramic brake disc. The lowest coefficient of friction in the AMS test is 0.26~0.27, the overall μ value sequence is more stable, and the thermal fading performance is excellent.

[0191] Example 4

[0192] Step 1: Preparation of carbon-coated modified molybdenum disulfide

[0193] 125.0 g of molybdenum disulfide powder and 125.0 g of glucose were added to 1.5 L of deionized water and ultrasonically dispersed for 45 min using an ultrasonic disperser (power 500 W) to obtain a uniform suspension.

[0194] The suspension was transferred to a polytetrafluoroethylene-lined hydrothermal reactor, sealed, and placed in an electric heating drying oven. The temperature was raised to 200°C, and the reaction was carried out for 10 hours.

[0195] After the reaction was completed, the mixture was naturally cooled to room temperature, filtered, washed three times with deionized water, and dried under vacuum at 80°C for 12 h to obtain the carbon-coated precursor.

[0196] The dried precursor was placed in a tube furnace, protected with nitrogen (flow rate 0.5 L / min), and heated to 600℃ at a rate of 5℃ / min, held for 2 h, and then carbonized and coated.

[0197] The product was cooled to room temperature in the furnace to obtain carbon-coated modified molybdenum disulfide. The finished product was sealed and stored for later use.

[0198] Step 2: Preparation of boron-modified phenolic resin

[0199] Add 100.0 g of phenol to a four-necked flask equipped with a stirrer and reflux device, add 4.0 g of sodium hydroxide, stir and heat to 70°C.

[0200] Slowly add about 126 g of formaldehyde solution (37% aqueous solution) while controlling the temperature at 85~90℃. After the addition is complete, keep the reaction at this temperature for 1.5 h.

[0201] Cool down to 75°C, add 30.0 g of boric acid, and continue to heat to 110°C, maintaining the temperature for 1.5 h.

[0202] Add approximately 54 g of formaldehyde solution (37% aqueous solution), heat to 105℃, and maintain the temperature until the viscosity reaches 80 mPa·s.

[0203] Dehydration under reduced pressure, with a vacuum of 0.06 MPa and the temperature gradually increased to 150°C, until the resin becomes transparent and viscous.

[0204] Cool the material down to below 50°C, discharge it, and you will get boron-modified phenolic resin. Seal the finished product and store it at low temperature for later use.

[0205] Step 3: Raw Material Preparation

[0206] Steel fibers, reduced iron powder, calcined alumina, silicon carbide, and potassium magnesium titanate flakes were ball-milled for 2 hours using a planetary ball mill at a speed of 400 r / min and a ball-to-material ratio of 10:1.

[0207] Weigh the following: 250.0 g boron-modified phenolic resin, 600.0 g steel fiber, 150.0 g aramid pulp, 450.0 g reduced iron powder, 400.0 g copper powder, 300.0 g brass powder, 250.0 g tin-copper alloy powder (Sn 10 wt%), 125.0 g Sn-Zn alloy powder (Sn 85 wt%, Zn 15 wt%), 250.0 g antimony trisulfide, 175.0 g carbon-coated modified molybdenum disulfide, 150.0 g zinc oxide powder, 350.0 g calcined alumina, 300.0 g silicon carbide, 450.0 g potassium magnesium titanate flakes, 350.0 g sericite, and 300.0 g vermiculite.

[0208] Step 4: Mixing

[0209] Using a high-speed plow mixer with a spindle speed of 140 r / min and a cutter speed of 3000 r / min, resin, fiber, metal filler (including Sn-Zn alloy powder), friction modifier (containing carbon-coated modified molybdenum disulfide), ceramic abrasive particles, and damping agent were added sequentially in three batches, stirring for 3-5 minutes each time to prevent agglomeration. The mixture was uniform in color, without obvious agglomeration, and had good flowability.

[0210] Step 5: Hot pressing

[0211] A flat vulcanizing machine was used, employing standard brake pad molds (friction block dimensions 150 mm × 60 mm × 12 mm), with a pressing pressure of 420 kg / cm². 2 The hot pressing temperature was 155℃, the holding time was 8 s / cycle, and the venting time was 3 s / cycle, for a total of 6 cycles. Friction material A was obtained.

[0212] Step 6: Post-curing heat treatment

[0213] Using an electric heating drying oven, the temperature was raised from room temperature to 205℃ at a rate of 3.5℃ / min, and held for 8 hours. The oven was then allowed to cool naturally to room temperature (approximately 12 hours) to obtain friction material B. The resin was completely cured and showed no obvious cracks.

[0214] Step 7: Machining

[0215] Use a surface grinder (accuracy 0.01 mm) to perform double-sided surface grinding, ensuring parallelism ≤0.02 mm and flatness ≤0.03 mm; chamfering is then performed.

[0216] Step 8: High-temperature surface short-time ablation treatment

[0217] A box-type resistance furnace was used at a temperature of 580℃ for 3.5 minutes. The first 1.5 minutes were under nitrogen protection (flow rate 2 L / min), followed by 2 minutes under a slightly oxidizing atmosphere (nitrogen + air 1:0.1) to remove the weak surface layer, resulting in a uniform gray-black protective layer.

[0218] Step Nine: Performance Testing

[0219] The testing equipment used was an inertial braking dynamometer, and the mating disc was an aluminum-based ceramic composite brake disc. The testing methods were: SAE J2522-2003 full-series test and AMS thermal decay series test. The test data are shown in Tables 4-1 and 4-2 below:

[0220]

[0221]

[0222] In this embodiment, the SAE J2522-2003 test results show that the nominal coefficient of friction reaches 0.43, the pressure sensitivity is 0.40~0.41, and the braking force linearity is significantly improved; the μ value in the high-temperature 500℃ test is 0.31, the lowest coefficient of friction is 0.31, and the recovery value after fading is 0.44~0.45, indicating a further reduction in the thermal fading amplitude and a further improvement in the recovery speed; the wear amount of the inner plate is 0.33 mm and the outer plate is 0.25 mm, which is about 20% lower than that in Examples 1 and 2, significantly improving the protection effect on the aluminum ceramic disc. The AMS test shows a lowest coefficient of friction of 0.27~0.28, with minimal fluctuation in the sequence μ value, indicating outstanding thermal fading performance. These results indicate that the introduction of boron-modified phenolic resin significantly enhances high-temperature stability.

[0223] Comparative Example 1

[0224] Step 1: Raw Material Preparation

[0225] Steel fibers, reduced iron powder, and copper powder were ball-milled for 2 hours using a planetary ball mill at a speed of 400 r / min and a ball-to-material ratio of 10:1.

[0226] Weigh 400.0 g of phenolic resin (type 2123, polymerization rate 40 s), 1000.0 g of steel fiber, 1500.0 g of reduced iron powder, 750.0 g of copper powder, 150.0 g of antimony trisulfide, 150.0 g of molybdenum disulfide (particle size <5 μm), 250.0 g of calcined alumina, 250.0 g of vermiculite, and 200.0 g of sericite.

[0227] Step 2: Mixing

[0228] Using a high-speed plow mixer with a spindle speed of 140 r / min and a cutter speed of 3000 r / min, resin, fiber, metal filler, friction modifier, ceramic abrasive, and damping agent were added sequentially in three batches, stirring for 3-5 minutes each time to prevent agglomeration. The mixture was uniform in color, without obvious agglomeration, and had good flowability.

[0229] Step 3: Hot pressing

[0230] A flat vulcanizing machine was used, employing standard brake pad molds (friction block dimensions 150 mm × 60 mm × 12 mm), with a pressing pressure of 420 kg / cm². 2 The hot pressing temperature was 155℃, the holding time was 8 s / cycle, and the venting time was 3 s / cycle, for a total of 6 cycles. Friction material A was obtained.

[0231] Step 4: Post-curing heat treatment

[0232] Using an electric heating drying oven, the temperature was raised from room temperature to 205℃ at a rate of 3.5℃ / min, and held for 8 hours. The oven was then allowed to cool naturally to room temperature (approximately 12 hours) to obtain friction material B. The resin was completely cured and showed no obvious cracks.

[0233] Step 5: Machining

[0234] Use a surface grinder (accuracy 0.01 mm) to perform double-sided surface grinding, ensuring parallelism ≤0.02 mm and flatness ≤0.03 mm; chamfering is then performed.

[0235] Step Six: Performance Testing

[0236] The testing equipment used was an inertial braking dynamometer, and the mating disc was an aluminum-based ceramic composite brake disc. The testing methods were: SAE J2522-2003 full-series test and AMS thermal decay series test. The test data are shown in Tables 5-1 and 5-2 below:

[0237]

[0238]

[0239] Comparative Example 1 uses a traditional cast iron disc with a high-metallic semi-metallic formulation. When matched with an aluminum-based ceramic composite brake disc, its friction performance is significantly insufficient. SAE J2522-2003 test results show a nominal coefficient of friction of only 0.33, high pressure sensitivity (0.31~0.33), and poor linearity of braking force. At a high temperature of 500℃, the μ value drops to 0.19, with a minimum coefficient of friction of 0.19, indicating severe degradation. The recovery value is only 0.33~0.35, showing a large thermal degradation range and slow recovery. The wear on the inner disc is 0.58 mm and the outer disc is 0.49 mm, indicating significant wear on the aluminum-ceramic disc. AMS testing shows a minimum coefficient of friction of 0.17~0.18, slightly lower than the passenger car standard requirement (>0.20), with a sharp drop in μ value in the later stages of the thermal degradation sequence. These results highlight the limitations of traditional semi-metallic formulations in matching aluminum-ceramic discs: low coefficient of friction, severe high-temperature degradation, and significant disc wear.

[0240] Comparative Example 2

[0241] Step 1: Raw Material Preparation

[0242] Steel fibers, reduced iron powder, calcined alumina, silicon carbide, and potassium magnesium titanate flakes were ball-milled for 2 hours using a planetary ball mill at a speed of 400 r / min and a ball-to-material ratio of 10:1.

[0243] Weigh the following: 250.0 g of phenolic resin (type 2123, polymerization rate 40 s), 600.0 g of steel fiber, 150.0 g of aramid pulp, 500.0 g of reduced iron powder, 400.0 g of copper powder, 300.0 g of brass powder, 250.0 g of tin-copper alloy powder (Sn 10 wt%), 250.0 g of antimony trisulfide, 250.0 g of molybdenum disulfide (particle size <5 μm), 100.0 g of zinc oxide powder, 350.0 g of calcined alumina, 300.0 g of silicon carbide, 450.0 g of potassium magnesium titanate flakes, 350.0 g of sericite, and 330.0 g of vermiculite.

[0244] Step 2: Mixing

[0245] Using a high-speed plow mixer with a spindle speed of 140 r / min and a cutter speed of 3000 r / min, resin, fiber, metal filler, friction modifier, ceramic abrasive, and damping agent were added sequentially in three batches, stirring for 3-5 minutes each time to prevent agglomeration. The mixture was uniform in color, without obvious agglomeration, and had good flowability.

[0246] Step 3: Hot pressing

[0247] A flat vulcanizing machine was used, employing standard brake pad molds (friction block dimensions 150 mm × 60 mm × 12 mm), with a pressing pressure of 420 kg / cm². 2 The hot pressing temperature was 155℃, the holding time was 8 s / cycle, and the venting time was 3 s / cycle, for a total of 6 cycles. Friction material A was obtained.

[0248] Step 4: Post-curing heat treatment

[0249] Using an electric heating drying oven, the temperature was raised from room temperature to 205℃ at a rate of 3.5℃ / min, and held for 8 hours. The oven was then allowed to cool naturally to room temperature (approximately 12 hours) to obtain friction material B. The resin was completely cured and showed no obvious cracks.

[0250] Step 5: Machining

[0251] Use a surface grinder (accuracy 0.01 mm) to perform double-sided surface grinding, ensuring parallelism ≤0.02 mm and flatness ≤0.03 mm; chamfering is then performed.

[0252] Step Six: Performance Testing

[0253] The testing equipment used was an inertial braking dynamometer, and the mating disc was an aluminum-based ceramic composite brake disc. The testing methods were: SAE J2522-2003 full-series test and AMS thermal decay series test. The test data are shown in Tables 6-1 and 6-2 below:

[0254]

[0255] The difference between Comparative Example 2 and Example 1 is that the high-temperature short-term ablation treatment on the surface was omitted. SAE J2522-2003 test results showed a nominal friction coefficient of 0.38, pressure sensitivity of 0.34–0.36, and acceptable braking linearity. However, the μ value dropped to 0.23 in the 500°C high-temperature test, with a minimum friction coefficient of 0.23 and a recovery value of 0.37–0.39 after degradation. The thermal degradation amplitude was greater than in Example 1, and the recovery speed was slower. The wear amount on the inner plate was 0.49 mm and on the outer plate was 0.42 mm, an increase of approximately 20% compared to Example 1, indicating accelerated wear on the aluminum ceramic disc. AMS testing showed a minimum friction coefficient of 0.20–0.21, with a significant decrease in μ value in the later stages of the sequence, indicating less stable thermal degradation performance than in Example 1. These results demonstrate that the high-temperature short-term ablation treatment on the surface plays a crucial role in the rapid formation of the initial transfer film, the removal of weak surface layers, and overall frictional stability and disc protection.

[0256] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the technical scope disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be within the scope of protection of the present invention.

Claims

1. A method for preparing a high-temperature stable resin-based friction material, characterized in that, Includes the following steps: S1. Weigh the thermosetting resin binder, reinforcing fiber, metal filler, friction modifier, ceramic abrasive, and damping agent in a mass ratio of (3~8):(10~25):(21~55):(5~15):(8~25):(8~23), and then put them into a high-speed mixer to mix evenly to obtain a mixture. S2. Place the mixture in a mold and hot press it to obtain friction material A; S3. The friction material A is subjected to post-curing heat treatment to completely cure the thermosetting resin adhesive and obtain friction material B; S4. The friction material B is machined; S5. The machined friction material B is subjected to high-temperature surface short-time ablation treatment to obtain a high-temperature stable resin-based friction material; in: The thermosetting resin binder is selected from 4 to 6 parts by weight of phenolic resin or modified phenolic resin. The reinforcing fiber comprises the following components by weight: 8-15 parts steel fiber and 2-5 parts aramid pulp; The metal filler comprises the following components by weight: 10-20 parts of reduced iron powder, 5-12 parts of copper powder, 5-12 parts of brass powder, 1-8 parts of tin-copper alloy powder, and 1-3 parts of low-melting-point tin-based alloy powder, wherein the low-melting-point tin-based alloy powder is a Sn-Zn alloy powder. The friction modifier comprises the following components by weight: 2-6 parts antimony trisulfide, 2-6 parts molybdenum disulfide solid lubricant, and 1-3 parts zinc oxide powder, wherein the molybdenum disulfide solid lubricant is selected from carbon-coated modified molybdenum disulfide. The ceramic abrasive comprises the following components by weight: 4-10 parts calcined alumina and 4-10 parts silicon carbide; The damping agent comprises the following components in parts by weight: 6-12 parts potassium magnesium titanate flakes, 3-6 parts sericite, and 2-5 parts vermiculite.

2. The preparation method according to claim 1, characterized in that, The thermosetting resin binder is boron-modified phenolic resin.

3. The preparation method according to claim 1, characterized in that: In step S1, the mixing time is 10~20 min, the spindle speed of the high-speed mixer is 100~200 r / min, and the speed of the flying knife is 2000~3500 r / min; In step S2, the hot pressing pressure is 300~500 kg / cm². 2 The molding temperature is 140~170℃, the holding time is 200~500s, and 4~10 venting operations are performed during the process, with each venting operation lasting no more than 5s. In step S3, the post-curing heat treatment involves heating to 180-220°C at a rate of 2-5°C / min, holding at that temperature for 4-12 hours, and then allowing it to cool naturally to room temperature. In step S4, the machining process includes surface grinding; In step S5, the high-temperature surface short-time ablation treatment temperature is 500~650℃, and the treatment time is 2~6min.

4. The preparation method according to claim 1, characterized in that, The carbon-coated modified molybdenum disulfide was prepared by the following steps: S01. Molybdenum disulfide powder and carbon source are dispersed in deionized water at a mass ratio of 1:(0.5~2), and ultrasonically dispersed for 30~60 min to obtain a uniform suspension, wherein the carbon source is selected from glucose or sucrose. S02. Transfer the suspension to a hydrothermal reactor and react at 180~220℃ for 6~12h; S03. After the reaction is complete, filter, wash and dry at 80~100℃ to obtain carbon-coated precursor; S04. The carbon-coated precursor is heat-treated at 500~700℃ for 1~3h under an inert atmosphere to obtain the carbon-coated modified molybdenum disulfide.

5. The preparation method according to claim 2, characterized in that, The boron-modified phenolic resin is prepared by the following steps: S001. Weigh phenol, formaldehyde, and boric acid in a molar ratio of (1~1.2):(1.2~1.8):(0.1~0.4); S002. Add phenol to the reaction vessel, add alkaline catalyst, stir and heat to 60~80℃, wherein the molar ratio of alkaline catalyst to phenol is 0.01~0.1; S003. Slowly add a portion of formaldehyde, with the added formaldehyde accounting for 60-80% of the total amount, and control the temperature at 80-95℃, and keep the reaction at this temperature for 1-2 hours; S004. Cool down to 70~80℃, add boric acid, and continue to heat to 100~120℃, and keep the temperature for 1~2 hours. S005. Add the remaining formaldehyde, heat to 92~110℃, and maintain the temperature until the viscosity reaches 50~100 mPa·s; S006. Dehydration under reduced pressure, controlling the vacuum degree to 0.04~0.08 MPa, and gradually increasing the temperature to 140~160℃; S007. When the resin becomes transparent or semi-transparent viscous, cool it to below 40~60℃ and discharge it to obtain the boron-modified phenolic resin.

6. The application of a high-temperature stable resin-based friction material prepared by the preparation method according to any one of claims 1 to 5, characterized in that, The high-temperature stable resin-based friction material is used in friction pads.

7. The application according to claim 6, characterized in that, The friction pads are used in friction pairs that match aluminum-based ceramic composite brake discs.

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