Bonding material and preparation method therefor, and brake pad and manufacturing method therefor

Abstract

A bonding material and a preparation method therefor, and a brake pad and a manufacturing method therefor. The bonding material comprises a resin material and filling particles, wherein the filling particles at least partially fill the resin material.

Description

Adhesive materials and their preparation methods and brake pads and their manufacturing methods

[0001] This application claims priority to Chinese patent application No. 202410698250.0, filed on May 30, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure relates to the field of brake pad technology, and in particular to an adhesive material and its preparation method, and a brake pad and its manufacturing method. Background Technology

[0003] Brake pads, also known as brake discs, are critical safety components in a car's braking system. Typically, brake pads consist of a friction layer composed of friction materials and adhesives. During braking, these materials are pressed against the brake disc or drum to generate friction, thereby achieving the purpose of slowing down and braking the vehicle. Resin materials are widely used as adhesives in the friction layer of brake pads. Summary of the Invention

[0004] This disclosure provides an adhesive material and its preparation method, as well as a brake pad and its manufacturing method, to solve the problem of brake pad high-temperature performance degradation caused by excessive resin material content in brake pads.

[0005] In a first aspect, some embodiments of this disclosure provide an adhesive material suitable for brake pads; the adhesive material includes a resin material and filler particles, at least a portion of the filler particles being filled in the resin material.

[0006] In some embodiments, the resin material accounts for 40%-60% of the mass of the adhesive material.

[0007] In some embodiments, the particle size D1 of the resin material satisfies: 20μm≤D1≤50μm.

[0008] In some embodiments, the resin material includes at least one of boron-modified phenolic resin, nitrile-modified phenolic resin, cashew nut shell liquid-modified phenolic resin, and silicone rubber-modified phenolic resin.

[0009] In some embodiments, the filler particles include ceramic particles, wherein the particle size D2 of the ceramic particles satisfies: 5μm≤D2≤20μm.

[0010] In some embodiments, the ceramic particles constitute 20%-30% of the mass of the adhesive material.

[0011] In some embodiments, the ceramic particles include at least one of feldspar, barite, iron oxide, diatomite, wollastonite, chromite, sulfides, zircon, corundum, cryolite, magnesium oxide, zinc oxide, barium sulfate, silicon carbide, copper oxide, iron powder, copper powder, aluminum powder, and magnesite.

[0012] In some embodiments, the filler particles further include rubber particles, wherein the particle size D3 of the rubber particles satisfies: 35μm≤D3≤75μm.

[0013] In some embodiments, the rubber particles constitute 20%-30% of the mass of the adhesive material.

[0014] In some embodiments, the rubber particles include at least one of styrene-butadiene rubber, tire powder, nitrile rubber, ethylene propylene rubber, asphalt, natural rubber, cashew nut shell oil friction powder, and amino ester powder.

[0015] Secondly, some embodiments of this disclosure provide a method for preparing an adhesive material, comprising: providing a resin material and filler particles; and filling at least a portion of the filler particles into the resin material.

[0016] Thirdly, some embodiments of this disclosure provide a brake pad, the brake pad including a friction layer, the friction layer including an adhesive material as described in any of the first aspects, or an adhesive material obtained by the method for preparing the adhesive material as described in the second aspect.

[0017] In some embodiments, the friction layer further includes fiber material, friction modifying material, and filler.

[0018] In some embodiments, the fiber material comprises 20%-30% by volume of the friction layer; the friction modulating material comprises 40%-60%; the filler comprises 15%-35%; and the binder comprises 5%-8%.

[0019] In some embodiments, the fiber material includes at least one of aramid fiber, ceramic fiber, composite mineral fiber, carbon fiber, and brass fiber.

[0020] In some embodiments, the friction-modifying material includes a friction-reducing material and a friction-enhancing material. The friction-reducing material includes at least one of graphite or metal sulfides, and the friction-enhancing material includes at least one of chromite powder, zircon powder, alumina, magnesium oxide, wollastonite, cryolite, carbon black, and silicon carbide.

[0021] In some embodiments, the filler includes at least one of vermiculite, mica powder, calcium oxide, titanium dioxide, calcium phosphate, zinc sulfate, iron oxide, zinc oxide, feldspar powder, corundum powder, bentonite, calcium silicate, potassium titanate, silicon dioxide, iron powder, copper powder, silicon powder, mullite, and barium sulfate.

[0022] In some embodiments, the friction layer satisfies at least one of the following: the density of the friction layer is 2.8 g / cm³. 3 -2.9g / cm 3 The porosity of the friction layer is 20%-22%; the impact strength of the friction layer is 4.0MPa-5.0MPa; the Rockwell hardness of the friction layer is 75HRR-90HRR; or, the coefficient of friction of the friction layer is 0.35-0.45.

[0023] In some embodiments, the brake pad further includes a backing plate, and the friction layer is connected to the backing plate; a first groove and a second groove are formed on the friction layer; the first groove and the second groove are adapted to guide flow to improve the braking effect of the brake pad.

[0024] In some embodiments, a third groove is further formed on the friction layer; the third groove is adapted to install an alarm device to monitor the thickness of the friction layer.

[0025] In some embodiments, the projection shape of the third groove on the back plate is a semicircle, and the radius of the semicircle is 10mm-12mm.

[0026] In some embodiments, the thickness H1 of the brake pad is 14mm-16mm; the thickness H2 of the backing plate is 4.5mm-5.5mm; the thickness H3 of the friction layer is 8mm-10mm; the depth H4 of the first groove and the second groove is 6mm-8mm; the depth H5 of the third groove is 8mm-10mm; the bottom surface of the first groove and the second groove is an arc surface with an arc radius of 0.2mm-0.5mm.

[0027] In some embodiments, one side of the friction layer is an arc, and the angle of the central angle corresponding to the arc is 5°-20°.

[0028] Fourthly, some embodiments of this disclosure provide a method for manufacturing a brake pad, comprising: preparing an adhesive material into a friction layer; and manufacturing the friction layer into a brake pad;

[0029] In some embodiments, preparing the bonding material into the friction layer includes: mixing fiber material, friction modifier material, filler and bonding material to obtain the friction layer; and making the friction layer into the brake pad includes: disposing the friction layer on a backing plate to obtain the brake pad.

[0030] Some embodiments of this disclosure provide an adhesive material suitable for brake pads; the adhesive material includes a resin material and filler particles, with at least some of the filler particles filling the resin material. Through this arrangement, at least some of the filler particles are filled into the resin material, forming a coating structure. This allows the resin material to increase its relative bonding area, thereby increasing its utilization rate and reducing the amount of resin material used. This prevents excessive resin material usage, avoids the problem of brake pad performance degradation at high temperatures due to thermal decomposition failure of the resin material, and improves the frictional performance of the adhesive material at high temperatures. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments or related technologies of this disclosure, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 is a cross-sectional view of the adhesive material according to some embodiments;

[0033] Figure 2A is a flowchart of a method for preparing an adhesive material according to some embodiments;

[0034] Figure 2B is a flowchart of another method for preparing the adhesive material according to some embodiments;

[0035] Figure 2C is a flowchart of another method for preparing the adhesive material according to some embodiments;

[0036] Figure 3 is a schematic diagram of a method for preparing an adhesive material according to some embodiments;

[0037] Figure 4 is a structural diagram of the adhesive material according to some embodiments;

[0038] Figure 5 is a flowchart of a method for manufacturing brake pads according to some embodiments;

[0039] Figure 6 is a SEM image of the adhesive material according to some embodiments;

[0040] Figure 7A is an EDS spectrum of the front side of the adhesive material according to some embodiments;

[0041] Figure 7B is an EDS spectrum of a cross section of the adhesive material according to some embodiments;

[0042] Figure 8A is a surface SEM image of the friction layer before a friction test according to some embodiments;

[0043] Figure 8B is a surface SEM image of the friction layer after a friction test according to some embodiments;

[0044] Figure 9 is a structural diagram of a three-dimensional mesh structure of composite material according to some embodiments;

[0045] Figure 10A is a flowchart of a method for preparing a composite material according to some embodiments;

[0046] Figure 10B is a flowchart of another method for preparing a composite material according to some embodiments;

[0047] Figure 11 is a structural diagram of a brake pad according to some embodiments;

[0048] Figure 12 is a top view of a sample of a brake pad according to some embodiments;

[0049] Figure 13 is a cross-sectional view of a brake pad sample according to some embodiments;

[0050] Figure 14 is a flowchart of a method for manufacturing brake pads according to some embodiments;

[0051] Figure 15 is a flowchart of another method for manufacturing brake pads according to some embodiments.

[0052] Reference numerals: 1-Adhesive material, 2-Resin material, 3-Filling particles, 31-Ceramic particles, 32-Rubber particles, 4-Brake pad, 5-Backplate, 6-Friction layer, 61-First groove, 62-Second groove, 63-Third groove, A-Graphite, B-Sulfide, 8-Substrate, 9-Friction material layer, 100-Sample, 11-First carbon fiber, 12-Second carbon fiber. Detailed Implementation

[0053] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0054] It should be noted that when a component is said to be "fixed" to another component, it can be directly on the other component or it can be in a middle component. When a component is said to be "connected" to another component, it can be directly connected to the other component or it may be in a middle component.

[0055] Unless otherwise defined, all technical and scientific terms used in this disclosure have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used in the specification of this disclosure is for illustrative purposes only and is not intended to be limiting of the disclosure. The term "and / or" as used in this disclosure includes any and all combinations of one or more of the associated listed items.

[0056] The following detailed description of some embodiments of this disclosure is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0057] Resin materials are widely used as binders in brake pad products. Resin decomposes at high temperatures. If the resin content in brake pads is too high, the brake pads will not have good friction performance at high temperatures. Brake pads with high resin content cannot stabilize the coefficient of friction at high temperatures. In addition, it will also reduce the bonding performance. During the friction process, the various components of the brake pads will fall off over a large area, resulting in a short service life of the brake pads.

[0058] Therefore, some embodiments of this disclosure provide an adhesive material 1 suitable for brake pads; referring to FIG1, the adhesive material 1 includes a resin material 2 and filler particles 3, with at least a portion of the filler particles 3 filling the resin material 2.

[0059] The brake pads contain an adhesive material 1 to ensure that the components of the brake pads are tightly bonded together, so that the brake pads can maintain structural integrity and provide structural strength even under continuous operation and high temperature environments. During braking, the adhesive material helps to distribute the stress transmitted by the brake disc evenly to the entire brake pad, thereby improving braking efficiency and reducing thermal stress, and preventing deformation or detachment under high temperature and mechanical stress.

[0060] Resin material 2, as the matrix of adhesive material 1, can firmly bond the components in the brake pad together to form a unified whole, ensuring the structural stability and integrity of the brake pad; effectively transmitting the force and heat generated by friction, ensuring that the brake pad can make uniform contact with the brake disc during braking, improving braking efficiency and reducing thermal stress.

[0061] Resin decomposes at high temperatures. High resin content leads to a significant decrease in the coefficient of friction of brake pads at high temperatures, and the brake pads cannot maintain a stable coefficient of friction, resulting in poor high-temperature resistance. Resin decomposition also reduces the adhesive properties of the resin. During friction, the components in the brake pads will fall off over a large area, resulting in excessive wear and a short lifespan for the brake pads.

[0062] At least some of the filler particles 3 are filled into the resin material 2, and the resin material 2 encapsulates the filler particles 3 to form a coating structure. This coating structure allows the resin material 2 to provide a larger relative bonding area, enabling the components in the brake pad to bond together and increasing the utilization rate of the resin. While ensuring that the resin material 2, as the matrix of the adhesive material 1, can firmly bond the components in the brake pad, the amount of resin used is reduced, minimizing fluctuations in the coefficient of friction due to resin thermal decomposition, thereby providing more stable braking performance. During high-temperature braking, the thermal decomposition products are reduced, allowing the brake pad to maintain better friction performance and structural integrity at high temperatures. Furthermore, the filler particles 3 have good wear resistance and mechanical properties, which can improve the wear resistance and friction performance of the brake pad.

[0063] For example, at least some of the filler particles 3 are uniformly filled in the resin material 2. Ideally, the filler particles 3 can be completely and uniformly distributed in the resin material 2. However, due to the limitations of the preparation method, some of the filler particles 3 will not be completely and uniformly filled in the resin material 2, but will be bound at the interface of the resin material 2. In actual work, this will not cause a significant impact on performance.

[0064] The adhesive material 1 provided in some embodiments of this disclosure is suitable for brake pads; the adhesive material 1 includes a resin material 2 and filler particles 3, with at least a portion of the filler particles 3 filling the resin material 2.

[0065] With the above settings, at least some of the filler particles 3 are filled into the resin material 2 to form a coating structure, which allows the resin material 2 to have a larger relative bonding area, increases the utilization rate of the resin material 2, thereby reducing the amount of resin material 2 used, preventing the problem of thermal decomposition failure of the resin material 2 at high temperature and the problem of brake pad performance degradation at high temperature due to excessive use of resin material 2, and thus helps to improve the friction performance of the bonding material 1 at high temperature.

[0066] When the particle size D1 of the resin material is less than 20μm, the resin material cannot coat the filler particles to form a more effective coating structure, thus reducing the utilization rate of the resin material.

[0067] When the particle size D1 of the resin material is greater than 50μm, the bonding performance is insufficient, which makes it impossible to effectively bond the components in the brake pad together and affects the overall structural stability of the brake pad.

[0068] In some embodiments, the particle size D1 of the resin material satisfies: 20 μm ≤ D1 ≤ 50 μm. For example, the particle size D1 of the resin material can be, but is not limited to, 20 μm, 30 μm, 40 μm, or 50 μm.

[0069] When the particle size D1 of the resin material is within this range, it can form a more effective coating structure with the filler particles, thereby improving the utilization rate of the resin material; it also enhances the bonding effect between the resin material and the components in the brake pad, thereby improving the overall structural stability.

[0070] When the resin material accounts for less than 40% of the mass of the adhesive material, it will result in insufficient bonding performance, weak bonding between the components in the brake pad, affecting the overall performance and durability of the brake pad; furthermore, it cannot improve the thermal conductivity of the brake pad, help dissipate heat, reduce heat accumulation, and thus improve the performance of the brake pad; and it will increase the noise and vibration generated during braking.

[0071] When the mass percentage of resin material in the binder is greater than 60%, it affects the friction performance of the brake pads, leading to an unstable coefficient of friction and affecting braking performance; excessive thermal decomposition of resin material also causes a decline in brake pad performance.

[0072] In some embodiments, the resin material accounts for 40%-60% of the mass of the adhesive material. For example, the mass percentage of the resin material in the adhesive material may be, but is not limited to, 40%, 55%, 60%, 55%, or 60%.

[0073] Within this mass ratio of resin material in the binder, the components in the brake pad can be effectively bonded together and form a uniform coating structure with the filler particles, enhancing the stability of the overall structure; improving the thermal conductivity of the brake pad, helping to dissipate heat, reducing heat accumulation, thereby improving the performance of the brake pad; reducing noise and vibration generated during braking, and improving driving comfort.

[0074] In some embodiments, the resin material includes at least one of boron-modified phenolic resin, nitrile-modified phenolic resin, cashew nut shell liquid-modified phenolic resin, and silicone rubber-modified phenolic resin.

[0075] For example, in some embodiments of this disclosure, the resin material may be one of boron-modified phenolic resin, nitrile-modified phenolic resin, cashew nut shell liquid-modified phenolic resin, or silicone rubber-modified phenolic resin. Alternatively, two or three of these resins may be used in combination.

[0076] When the particle size D2 of ceramic particles is less than 5μm, the friction coefficient of the brake pads becomes too high, which may affect the stability and controllability of the braking system. The particles are difficult to disperse evenly in the resin matrix, and the amount of resin used cannot be effectively reduced. The thermal conductivity of the brake pads is reduced, making it difficult for heat to dissipate, thereby increasing thermal stress and affecting the high-temperature resistance of the brake pads.

[0077] When the particle size D2 of ceramic particles is greater than 20μm, it leads to a decrease in the wear resistance of brake pads, increases the noise and vibration generated during braking, and affects driving comfort; large particles hinder heat conduction, leading to local overheating and thermal decomposition of resin around the large particles.

[0078] In some embodiments, referring to Figures 1 and 3, the filler particles 3 include ceramic material 31, and the particle size D2 of the ceramic particles satisfies: 5μm≤D2≤20μm. For example, the particle size D2 of the ceramic particles can be, but is not limited to, 5μm, 10μm, 15μm, or 20μm.

[0079] Ceramic particles have a high melting point and good thermal stability, which enables them to maintain their structural integrity in the high-temperature environment during brake pad operation, and they are not easily softened or decomposed. They also have excellent hardness and wear resistance, which can significantly improve the wear resistance of brake pads during braking and extend their service life. Their thermal conductivity is usually higher than that of resin materials, which helps to improve the heat conduction performance of brake pads, quickly dissipate the heat generated by friction, and reduce heat accumulation.

[0080] The particle size D2 of ceramic particles within this range can optimize the friction coefficient of brake pads; provide good wear resistance and enhance the mechanical strength of brake pads; improve the thermal conductivity of brake pads, so that heat can be more effectively dispersed and conducted, reducing thermal stress; and improve the utilization rate of resin materials, because they can be more evenly distributed in the resin matrix to form a more effective coating structure.

[0081] When the mass percentage of ceramic particles in the binder is less than 20%, the amount of ceramic particles is too small to form a sufficient coating structure, thus failing to improve the utilization rate of the resin material and reducing the resin content in the brake pads. This results in insufficient wear resistance and thermal stability, leading to poor stability and wear resistance in the brake pad's coefficient of friction.

[0082] When the mass percentage of ceramic particles in the bonding material exceeds 30%, excessive ceramic particles affect the bonding effect of the resin material, resulting in a weak bond between the ceramic particles and the resin material, which affects the overall structural strength of the brake pads; it also increases the noise and vibration generated during braking, affecting driving comfort.

[0083] In some embodiments, the ceramic particles constitute 20%-30% of the mass of the adhesive material. For example, the mass percentage of ceramic particles in the adhesive material may be, but is not limited to, 20%, 22%, 24%, 26%, 28%, or 30%.

[0084] Within this mass ratio of ceramic particles in the binder, they can be uniformly distributed in the resin matrix, forming a more effective coating structure, improving the utilization rate of resin materials, reducing the resin content in brake pads, providing sufficient wear resistance and thermal stability for brake pads, reducing brake pad thermal fade, maintaining the stability of the brake pad friction coefficient, improving the wear resistance of brake pads, extending their service life, and reducing replacement frequency and maintenance costs.

[0085] When the particle size D3 of the rubber particles is less than 35μm, the rubber particles are too small and it is difficult to disperse them evenly in the resin material during the mixing process. They cannot form a sufficient coating structure, which reduces the utilization rate of the resin material; it also increases the noise and vibration generated during braking, affecting driving comfort.

[0086] When the particle size D3 of the rubber particles is greater than 75μm, the excessively large volume of the rubber particles leads to a reduction in the relative bonding area of ​​the resin material in the formed coating structure, thus reducing the utilization rate of the resin material.

[0087] In some embodiments, referring to Figures 1 and 3, the filler particle 3 further includes rubber particles 32, the particle size D3 of which satisfies: 35μm≤D3≤75μm. For example, the particle size D3 of the rubber particles can be, but is not limited to, 35μm, 45μm, 55μm, 65μm, or 75μm.

[0088] The filler particles also include rubber particles, which can absorb and mitigate vibrations and noise during braking, reduce the impact on the vehicle and passengers, and improve driving comfort; they are evenly distributed in the resin material to form an effective coating structure, improve the utilization rate of the resin material, and thus reduce the resin material content.

[0089] When the particle size D3 of the rubber granules is within this range, it can absorb and mitigate vibrations and noise during braking, improving driving comfort; it can also be more evenly distributed in the resin matrix, forming a more effective coating structure, thereby reducing the amount of resin material.

[0090] When the mass percentage of rubber particles in the bonding material is less than 20%, the contribution of rubber particles to reducing noise and vibration decreases, which may lead to a decrease in comfort during braking; and too few rubber particles cannot form a sufficient coating structure, thus failing to reduce the content of resin materials.

[0091] When the mass percentage of rubber particles in the bonding material exceeds 30%, it will reduce the friction coefficient of the brake pads, leading to a decrease in the wear resistance of the brake pads and affecting the braking performance.

[0092] In some embodiments, the rubber particles constitute 20%-30% of the adhesive material by mass. For example, the mass percentage of rubber particles in the adhesive material may be, but is not limited to, 20%, 22%, 24%, 26%, 28%, or 30%.

[0093] Within this mass ratio of rubber particles in the adhesive material, the rubber particles can effectively absorb and mitigate vibrations and noise during braking, reduce the impact on the vehicle and passengers, and improve driving comfort; they are also evenly distributed in the resin material to form a more effective coating structure and improve the utilization rate of the resin material.

[0094] In some embodiments, the rubber particles include at least one of styrene-butadiene rubber, tire powder, nitrile rubber, ethylene propylene rubber, asphalt, natural rubber, cashew nut shell oil friction powder, and amino ester powder.

[0095] For example, in some embodiments of this disclosure, the rubber particles may be one of styrene-butadiene rubber, tire powder, nitrile rubber, ethylene propylene rubber, asphalt, natural rubber, cashew nutshell oil friction powder, and amine ester powder. The rubber particles may also be a mixture of multiple types of styrene-butadiene rubber, tire powder, nitrile rubber, ethylene propylene rubber, asphalt, natural rubber, cashew nutshell oil friction powder, and amine ester powder.

[0096] In some embodiments, the ceramic particles include at least one of feldspar, barite, iron oxide, diatomite, wollastonite, chromite, sulfides, zircon, corundum, cryolite, magnesium oxide, zinc oxide, barium sulfate, silicon carbide, copper oxide, iron powder, copper powder, aluminum powder, and magnesite.

[0097] For example, in some embodiments of this disclosure, the ceramic particles may be one of feldspar, barite, iron oxide, diatomite, wollastonite, chromite, sulfides, zircon, corundum, cryolite, magnesium oxide, zinc oxide, barium sulfate, silicon carbide, copper oxide, iron powder, copper powder, aluminum powder, and magnesite. The ceramic particles may also be a mixture of various minerals, including feldspar, barite, iron oxide, diatomite, wollastonite, chromite, sulfides, zircon, corundum, cryolite, magnesium oxide, zinc oxide, barium sulfate, silicon carbide, copper oxide, iron powder, copper powder, aluminum powder, and magnesite.

[0098] The preparation method of the adhesive material provided in some embodiments of this disclosure is shown in Figure 2A. The preparation method includes steps S1 to S2.

[0099] Step S1: Provide resin material and filler particles.

[0100] Step S2: Fill at least part of the filler particles into the resin material.

[0101] By filling at least some of the filler particles into the resin material, a bonding material with a coating structure is prepared in which the resin material encapsulates the filler particles. The bonding material with the coating structure allows the resin material to provide a larger relative bonding area to bond the various components in the brake pad, increasing the resin utilization rate, reducing the amount of resin used, and reducing the fluctuation of the friction coefficient caused by the thermal decomposition of the resin, thereby providing more stable braking performance. During high-temperature braking, the thermal decomposition products are reduced, thereby allowing the brake pad to maintain better friction performance and structural integrity at high temperatures.

[0102] In some embodiments, as shown in FIG2B, step S2 includes steps S21 and S22.

[0103] Step S21: Dissolve the resin material in the solution and stir to obtain solution A.

[0104] For example, the resin material can be at least one of boron-modified phenolic resin, nitrile-modified phenolic resin, cashew nut shell liquid-modified phenolic resin, and silicone rubber-modified phenolic resin. The solution can be an alcohol solution, including but not limited to methanol solution, ethanol solution, ethylene glycol solution, and propanol solution. The mass ratio of resin material to solution is 1:1. The stirring speed is 500 r / min-1500 r / min.

[0105] Step S22: Add rubber particles to solution A, stir, dry, and crush to obtain powder A.

[0106] In some embodiments, as shown in FIG2C, step S2 above includes the following steps S21 to S23.

[0107] Step S21: Dissolve the resin material in the solution and stir to obtain solution A.

[0108] Step S22: Add rubber particles to solution A, stir, dry, and crush to obtain powder A.

[0109] Step S23: Mix powder A with ceramic particles, melt, stir, and extrude to obtain a binder material.

[0110] For example, in step S21, the resin material can be at least one of boron-modified phenolic resin, nitrile-modified phenolic resin, cashew nut shell liquid-modified phenolic resin, and silicone rubber-modified phenolic resin. The solution can be an alcohol solution, including but not limited to methanol solution, ethanol solution, ethylene glycol solution, and propanol solution.

[0111] In some embodiments, the mass ratio of resin material to solution can be 1:1. The stirring speed is 500 r / min-1500 r / min.

[0112] For example, in step S22, the rubber particles can be at least one of styrene-butadiene rubber, tire powder, nitrile rubber, ethylene propylene rubber, asphalt, natural rubber, cashew nut shell oil friction powder, and amino ester powder.

[0113] It needs to be explained that step S22 is the first step of "expansion" of the adhesive material. Through the first step of "expansion", the rubber particles can be evenly dispersed in the resin material, thereby increasing the volume of the adhesive material.

[0114] For example, in step S23, the mass ratio of powder A to ceramic particles is 1:(3-5).

[0115] In some embodiments, the mass ratio of powder A to ceramic particles is 1:3. The melting temperature is 120℃-160℃. The stirring time is 1h-4h, for example, 2h. The extruded material is passed through a 500-mesh sieve.

[0116] It needs to be explained that step S23 is the second step of the adhesive material, "volume expansion". After the powder A is melted at high temperature, it is mixed with ceramic particles. Under the action of external force, the ceramic particles are squeezed into the interior of the resin material, forming a composite structure in which the resin material encapsulates the ceramic particles and rubber particles, thereby further expanding the volume of the adhesive material.

[0117] By creating a structure in which resin material coats ceramic and rubber particles, resin utilization is increased. Using the same volume of resin material, a larger volume of adhesive material can be produced, thereby reducing resin consumption. In some embodiments of this disclosure, the ceramic particles within the adhesive material of the brake pads continue to function under high-temperature operating conditions, stabilizing the brake pad's coefficient of friction at 0.35 or higher and improving its heat resistance.

[0118] Some embodiments of this disclosure provide brake pads, which include a friction layer comprising the adhesive material as described above, or an adhesive material obtained by the preparation method of the adhesive material as described in the above embodiments.

[0119] The friction layer contacts the brake disc or brake drum, causing the brake pads to generate friction, which slows down or stops the vehicle. The bonding material in the friction layer allows the brake pads to maintain better friction performance and structural integrity at high temperatures.

[0120] In some embodiments, the friction layer further includes fiber material, friction modifying material, and filler.

[0121] Fiber materials enhance the mechanical strength and toughness of the friction layer, improving the impact resistance of the brake pads. Friction conditioning materials adjust the friction coefficient of the brake pads to adapt to different braking conditions. Fillers increase the density and hardness of the friction layer, improving friction performance and wear resistance, enhancing the wear resistance of the friction material layer, and extending the service life of the brake pads.

[0122] When the proportion of fiber material is less than 20%, the proportion of fiber material is too low and may not provide sufficient reinforcement, resulting in insufficient mechanical strength and toughness of the friction layer, which affects the impact resistance and wear resistance of the brake pad.

[0123] When the proportion of fiber material in the friction layer is greater than 30%, the excessive proportion of fiber material will lead to increased material costs, and the components in the friction layer will not be well matched, affecting the performance of the brake pads.

[0124] In some embodiments, the fiber material accounts for 20%-30% of the friction layer by volume percentage; for example, the fiber material may be, but is not limited to, 20%, 22%, 24%, 26%, 28%, or 30% of the friction layer by volume percentage.

[0125] Within this range, the proportion of fiber material can enhance the mechanical strength and toughness of the friction layer, improve the impact resistance and wear resistance of the brake pads, improve the stability of the friction layer at high temperatures, reduce thermal degradation, maintain the performance of the brake pads, and extend the service life of the brake pads.

[0126] When the proportion of friction conditioning material is less than 40%, the wear resistance of the friction layer is insufficient, which leads to accelerated wear of the brake pads during long-term use and shortens their service life; it also fails to effectively improve the stability of the friction layer under wear conditions, resulting in performance fluctuations of the brake pads.

[0127] When the proportion of friction modulating material is greater than 60%, the excessive proportion of wear-resistant material will lead to increased material costs and waste of resources.

[0128] In some embodiments, the friction modulating material accounts for 40%-60% of the friction layer by volume percentage; for example, the friction modulating material may be, but is not limited to, 40%, 45%, 50%, 55%, or 60%.

[0129] Within this range, the proportion of friction modifier material can improve the wear resistance of the friction layer, thereby extending the service life of the brake pads; it can also improve the stability of the friction layer at high temperatures, reduce thermal degradation, and maintain the performance of the brake pads.

[0130] When the filler content is less than 15%, it is insufficient to improve the density and hardness of the friction layer, affecting friction performance and wear resistance; it leads to thermal degradation, affecting the performance of the brake pads; and it reduces the wear resistance of the friction layer, shortening the service life of the brake pads.

[0131] When the filler content exceeds 35%, the material cost will increase, the components in the friction layer will not be compatible, and the performance of the brake pads will be affected.

[0132] In some embodiments, the filler accounts for 15%-35% of the friction layer by volume percentage; for example, the filler may be, but is not limited to, 15%, 17%, 19%, 21%, 23%, 25%, 27%, 29%, 31%, 33%, or 35%.

[0133] Within this range, the proportion of filler can increase the density and hardness of the friction layer, improve friction performance and wear resistance; enhance the stability of the friction layer at high temperatures, reduce thermal degradation, and maintain the performance of the brake pads; improve the wear resistance of the friction layer and extend the service life of the brake pads.

[0134] When the proportion of adhesive material is less than 5%, the adhesion of the components inside the friction material layer is insufficient, which cannot provide a sufficient bonding effect, resulting in internal defects in the material and affecting the overall structural strength and performance of the brake pad.

[0135] When the proportion of adhesive material is greater than 8%, the adhesive performance is excessive, resulting in a waste of resources.

[0136] In some embodiments, the adhesive material comprises 5%-8% by volume percentage of the friction layer. For example, the adhesive material may be, but is not limited to, 5%, 6%, 7%, or 8%.

[0137] Within this range, the proportion of adhesive material can enhance the adhesion of the components inside the friction layer, improve the overall structural strength of the brake pad, improve the uniformity of the friction layer, and reduce internal defects.

[0138] In some embodiments, the fiber material includes at least one of aramid fiber, ceramic fiber, composite mineral fiber, carbon fiber, and brass fiber.

[0139] For example, the fiber material can be one of aramid fiber, ceramic fiber, composite mineral fiber, carbon fiber, or brass fiber. It can also be a combination of multiple aramid fibers, ceramic fibers, composite mineral fibers, carbon fibers, and brass fibers.

[0140] When the fiber material includes aramid, the aramid fiber length is 2mm-2.5mm and the diameter is 1μm-2μm; when the fiber material includes ceramic fiber, the ceramic fiber length is 1mm-1.5mm and the diameter is 20μm-50μm; when the fiber material includes composite mineral fiber, the composite mineral fiber length is 1mm-2.5mm and the diameter is 5μm-10μm; when the fiber material includes carbon fiber, the carbon fiber length is 0.1mm-0.5mm and the diameter is 5μm-10μm; when the fiber material includes brass fiber, the brass fiber length is 1.5mm-2mm and the diameter is 10μm-20μm.

[0141] In some embodiments, the friction-modifying material includes a friction-reducing material and a friction-enhancing material. The friction-reducing material includes at least one of graphite or metal sulfides, and the friction-enhancing material includes at least one of chromite powder, zircon powder, alumina, magnesium oxide, wollastonite, cryolite, carbon black, and silicon carbide.

[0142] Friction-reducing materials in friction-adjusting materials lower the coefficient of friction of brake pads, reducing wear during braking and improving brake pad durability. Friction-enhancing materials in friction-adjusting materials increase the coefficient of friction of brake pads, providing sufficient braking force to ensure effective braking under various operating conditions. This optimizes brake pads, providing a stable coefficient of friction and excellent wear resistance under various conditions, ensuring sufficient braking force during braking and maintaining a long service life.

[0143] For example, the graphite may be, but is not limited to, at least one of artificial graphite and expanded graphite, and the graphite fineness is 800μm-1500μm.

[0144] For example, the metal sulfide may be, but is not limited to, at least one of tin sulfide, antimony sulfide, copper sulfide, molybdenum sulfide, and ferrous sulfide, and the fineness of the metal sulfide is 1000-1200 mesh.

[0145] The grinding aid material can be one of the following: chromite powder, zircon powder, alumina, magnesium oxide, wollastonite, cryolite, carbon black, or silicon carbide. Alternatively, it can be a combination of these materials. The fineness of the grinding aid material is 300-500 mesh.

[0146] In some embodiments, the filler includes at least one of vermiculite, mica powder, calcium oxide, titanium dioxide, calcium phosphate, zinc sulfate, iron oxide, zinc oxide, feldspar powder, corundum powder, bentonite, calcium silicate, potassium titanate, silicon dioxide, iron powder, copper powder, silicon powder, mullite, and barium sulfate.

[0147] For example, the filler can be one or more of the following: vermiculite, mica powder, calcium oxide, titanium dioxide, calcium phosphate, zinc sulfate, iron oxide, zinc oxide, feldspar powder, corundum powder, bentonite, calcium silicate, potassium titanate, silicon dioxide, iron powder, copper powder, silica powder, mullite, and barium sulfate. For example, the fineness of the filler is 1000 mesh to 1500 mesh.

[0148] When the density of the friction layer is less than 2.8 g / cm³ 3 This leads to uneven material properties, causing the brake pad performance to fluctuate under different conditions, resulting in poor thermal stability of the friction layer and making it more prone to wear; thus affecting the performance of the brake pad.

[0149] When the density of the friction layer is greater than 2.9 g / cm³ 3When brake pads are used, their weight increases, leading to a longer braking response time and affecting braking performance.

[0150] In some embodiments, the density of the friction layer is 2.8 g / cm³. 3 -2.9g / cm 3 For example, the density of the friction layer can be, but is not limited to, 2.8 g / cm³. 3 2.82 g / cm 3 2.84 g / cm 3 2.86 g / cm 3 2.88g / cm 3 2.9g / cm 3 .

[0151] Within this density range, the friction layer can be guaranteed to have uniform performance, reduce performance fluctuations, and improve the stability and reliability of the brake pads; it can also improve the wear resistance and thermal stability of the friction layer and extend the service life of the brake pads.

[0152] When the porosity of the friction layer is less than 20%, the efficiency of heat conduction and diffusion is reduced, leading to heat accumulation during braking and affecting the performance and lifespan of the brake pads.

[0153] When the porosity of the friction layer is greater than 22%, it will reduce the contact area in the friction layer, thereby reducing the coefficient of friction and affecting the braking effect of the brake pads; it will also reduce the overall structural strength of the material, affecting the durability and reliability of the brake pads.

[0154] In some embodiments, the porosity of the friction layer is 20%-22%. For example, the porosity of the friction layer may be, but is not limited to, 20%, 20.5%, 21%, 21.5%, or 22%.

[0155] Within this range of porosity, the heat conduction efficiency of the friction layer can be improved, allowing the heat generated by the brake pads during braking to be dissipated more effectively, reducing heat accumulation, preventing overheating, and thus improving the performance and lifespan of the brake pads.

[0156] When the impact strength of the friction layer is less than 4.0 MPa, the brake pads are prone to cracking and breaking when subjected to impact, which can lead to damage to the brake pads during use and create safety hazards.

[0157] When the impact strength of the friction layer exceeds 5.0 MPa, the design becomes redundant, requiring the use of higher-performance materials, which increases the overall cost of the brake pads.

[0158] In some embodiments, the impact strength of the friction layer is 4.0 MPa-5.0 MPa. For example, the impact strength of the friction layer may be, but is not limited to, 4 MPa, 4.2 MPa, 4.4 MPa, 4.6 MPa, 4.8 MPa, or 5 MPa.

[0159] Within this range of impact strength of the friction layer, the brake pads can maintain structural integrity when subjected to impact forces, reducing the risk of cracks and fractures, thereby improving the durability and safety of the brake pads.

[0160] When the impact strength of the friction layer is less than 4.0 MPa, the brake pads are prone to cracking and breaking when subjected to impact, which can lead to damage to the brake pads during use and create safety hazards.

[0161] When the impact strength of the friction layer exceeds 5.0 MPa, the design becomes redundant, requiring the use of higher-performance materials, which increases the overall cost of the brake pads.

[0162] In some embodiments, the Rockwell hardness of the friction layer is 75 HRR-90 HRR. For example, the Rockwell hardness of the friction layer may be, but is not limited to, 75 HRR, 80 HRR, 85 HRR, or 90 HRR.

[0163] Within this range of impact strength of the friction layer, the brake pads can maintain structural integrity when subjected to impact forces, reducing the risk of cracks and fractures, thereby improving the durability and safety of the brake pads.

[0164] When the coefficient of friction of the brake pads is less than 0.35, they cannot provide sufficient braking force during braking.

[0165] When the coefficient of friction of the brake pads is greater than 0.45, it leads to increased wear between the brake pads and the brake disc, resulting in more noise and wear particles.

[0166] In some embodiments, the friction coefficient of the friction layer is 0.35-0.45. For example, the friction coefficient of the friction layer may be, but is not limited to, 0.35, 0.37, 0.39, 0.41, 0.43, or 0.45.

[0167] With the friction coefficient of the friction layer within this range, the braking performance of the brake pads can be kept relatively stable. Excessive wear or heat accumulation due to an excessively high friction coefficient will not occur, nor will poor braking performance due to an excessively low friction coefficient.

[0168] In some embodiments, please refer to FIG4, the brake pad 4 further includes a back plate 5, and a friction layer 6 is connected to the back plate 5; a first groove 61 and a second groove 62 are formed on the friction layer 6; the first groove 61 and the second groove 62 are adapted to guide flow to improve the braking effect of the brake pad 4.

[0169] The backplate 5 provides structural support for the friction layer 6, ensuring that the friction layer 6 can withstand the mechanical and thermal stresses during braking, while providing effective friction performance; the base disperses the heat generated by the friction layer 6 during braking, reducing thermal stress and improving the durability of the brake pad 4.

[0170] A first groove 61 and a second groove 62 are formed on the friction layer 6. These grooves are designed to guide water flow, thereby improving the braking effect of the brake pad 4. By providing the first groove 61 and the second groove 62, water adhering to the surface of the friction layer 6 can be guided away. The presence of water reduces the coefficient of friction of the friction layer 6, increasing the braking distance and preventing slippage during braking due to water on the surface of the friction layer 6. Additionally, the first groove 61 and the second groove 62 can guide away wear debris generated during friction, preventing excessive debris from causing sticking wear and resulting in poor braking performance. This also helps increase the surface area of ​​the brake pad 4, improving heat dissipation and reducing heat accumulation. This helps maintain the performance stability of the brake pad 4 under high-temperature conditions and reduces heat fade.

[0171] In some embodiments, a third groove 63 is further provided on the friction layer 6; the third groove 63 is adapted to install an alarm device to monitor the thickness of the friction layer 6.

[0172] A third groove 63 is formed on the friction layer 6, and an alarm device is installed at the third groove 63. When the friction layer 6 is worn to a certain extent, that is, when the thickness is reduced to below the preset threshold, the alarm device will trigger an alarm signal to prompt the replacement of the brake pad 4.

[0173] In some embodiments, the projection shape of the third groove on the back plate is a semicircle with a radius of 10mm-12mm. For example, the radius of the semicircle can be, but is not limited to, 10mm, 10.5mm, 11mm, 11.5mm, or 12mm.

[0174] The projection shape of the third groove on the back plate is a semi-circle to accommodate the alarm device. The radius of the semi-circle can be adapted to the alarm device that meets the size requirements.

[0175] When the thickness H1 of the brake pads is less than 14mm, the brake pads are too thin, resulting in insufficient friction during braking. This causes the brake pads to wear out faster during braking, leading to more frequent replacements and increased maintenance costs.

[0176] When the thickness H1 of the brake pads is greater than 16mm, the thicker brake pads may exceed the actual braking performance required, resulting in design redundancy and increasing unnecessary costs and resource consumption.

[0177] In some embodiments, the thickness H1 of the brake pad is 14mm-16mm. For example, the thickness H1 of the brake pad can be, but is not limited to, 14mm, 15mm, or 16mm.

[0178] The brake pad thickness H1 is within this range, which can maintain the performance of the brake pad, provide stable braking performance, reduce costs, and achieve a lightweight design.

[0179] When the thickness H2 of the backplate is less than 4.5mm, it cannot provide sufficient structural stability and is prone to deformation or damage during braking, affecting the performance of the brake pads.

[0180] When the thickness H2 of the backplate is greater than 5.5mm, it cannot effectively disperse the heat generated during braking, affecting the performance of the brake pads.

[0181] In some embodiments, the thickness H2 of the brake backplate is 4.5mm-5.5mm. For example, the thickness H2 of the backplate can be, but is not limited to, 4.5mm, 5mm, or 5.5mm.

[0182] The thickness H2 of the backing plate is within this range, which can provide sufficient structural stability for the friction layer, ensuring that the brake pads can withstand mechanical and thermal stress during braking; it helps to disperse the heat generated during braking, improve thermal management capabilities, and prevent the brake pads from overheating.

[0183] In some embodiments, the thickness H3 of the friction layer is 8mm-10mm. For example, the thickness H3 of the friction layer can be, but is not limited to, 8mm, 9mm, or 10mm.

[0184] The thickness H3 of the friction layer is set for the same reason as the thickness H1 of the brake pad, which will not be repeated here.

[0185] When the depth H4 of the first and second grooves is less than 6mm, water and wear debris cannot be removed, affecting the performance and lifespan of the brake pads.

[0186] When the depth H4 of the first and second tanks is greater than 8mm, it exceeds the actual required range, resulting in overperformance and increased manufacturing and processing costs.

[0187] In some embodiments, the depth H4 of the first and second grooves is 6mm-8mm. For example, the thickness H3 of the friction layer can be, but is not limited to, 8mm, 9mm, or 10mm.

[0188] The depth H4 of the first and second tanks is within this range, which helps to improve the flow efficiency of the first and second tanks, quickly guide water and wear debris away from the surface of the friction layer, and reduce the impact on the friction layer.

[0189] When the depth H5 of the third groove is less than 8mm, the alarm device is not installed stably, which may cause the alarm device to become unstable during the use of the brake pads, and may result in loosening or displacement, affecting the normal operation of the alarm device.

[0190] When the depth H5 of the third tank is greater than 10mm, it exceeds the actual required range, resulting in performance overkill and increased manufacturing and processing costs.

[0191] In some embodiments, the depth H5 of the third groove is 8mm-10mm. For example, the depth H5 of the third groove can be, but is not limited to, 8mm, 9mm, or 10mm.

[0192] The depth H5 of the third groove is within this range, which can accommodate the alarm device and provide sufficient structural stability to ensure that the alarm device will not loosen or shift due to vibration or wear during the use of the brake pads.

[0193] When the radius of the arc where the bottom surfaces of the first and second grooves are located is less than 0.02 mm, wear debris and moisture accumulate at the bottom of the grooves, exacerbating the wear of the friction layer.

[0194] When the radius of the arc where the bottom surfaces of the first and second grooves are located is greater than 0.04 mm, the strength of the groove structure decreases, affecting the overall stability of the brake pads.

[0195] In some embodiments, the bottom surfaces of the first and second grooves are arc surfaces, and the radius of the arc surface is 0.2mm-0.5mm. For example, the radius of the arc surface of the bottom surfaces of the first and second grooves can be, but is not limited to, 0.2mm, 0.3mm, 0.4mm, or 0.5mm.

[0196] The bottom surfaces of the first and second tanks are curved, preventing wear debris and water from accumulating at the bottom and reducing direct wear. The radii of the arcs containing the bottom surfaces of the first and second tanks are within this range, ensuring that wear debris and water are quickly washed away, further reducing wear.

[0197] When the central angle corresponding to the arc is less than 5°, the excessively small central angle causes the edge of the brake pad to contact the brake disc too tightly, increasing edge wear, while the wear in the middle area is lighter, resulting in uneven wear.

[0198] When the central angle corresponding to the arc is greater than 10°, it affects the braking performance of the brake pads, reduces the coefficient of friction, and decreases the braking effect.

[0199] In some embodiments, one side of the friction layer is an arc, and the central angle corresponding to the arc is 5°-20°. For example, the central angle corresponding to the arc can be, but is not limited to, 5°, 7°, 9°, 11°, 13°, 15°, 17°, 19°, or 20°.

[0200] The rounded edges reduce direct contact between the friction layer and the brake disc, thereby reducing edge wear and extending brake pad life. Furthermore, they improve structural stability, such as reducing noise and vibration.

[0201] The angle of the central angle corresponding to the arc is within this range, which can reduce brake pad wear, reduce edge wear, and maintain the integrity of the friction layer surface.

[0202] Some embodiments of this disclosure also provide a method for manufacturing brake pads. Please refer to Figure 5. The method includes steps S10 to S20.

[0203] Step S10: Prepare the adhesive material into a friction layer.

[0204] Step S20: The friction layer is made into a brake pad.

[0205] For example, in step S10, the fiber material, friction modifier, filler and binder are mixed and molded. The molding temperature is 150-170℃, the molding pressure is 25-50MPa, and the holding time is 5-15min.

[0206] The programmed temperature curing process involves holding at 140℃-170℃ for 3 hours, then raising the temperature to 170℃-200℃ and holding for 4 hours, and finally raising the temperature to 240℃ and holding for 8 hours to obtain the friction layer. The friction layer is prepared from the adhesive material with the encapsulation structure, and then the friction layer is used to fabricate the brake pad. This reduces the amount of resin used in the friction layer, thereby reducing fluctuations in the coefficient of friction caused by resin thermal decomposition, resulting in more stable braking performance. During high-temperature braking, the thermal decomposition products of the friction layer are reduced, allowing the brake pad to maintain better friction performance and structural integrity at high temperatures.

[0207] In some embodiments, preparing the bonding material into a friction layer includes: mixing a fiber material, a friction modifier, a filler, and a bonding material to obtain a friction layer; and making the friction layer into a brake pad includes: depositing the friction layer on a backing plate to obtain a brake pad.

[0208] A friction layer is obtained by mixing fiber material, friction modifier, filler, and binder. The fiber material enhances the mechanical strength and toughness of the friction layer; the friction modifier improves wear resistance; the filler increases density and hardness; and the binder bonds the components together. The resulting friction layer is then loaded onto a substrate to form a brake pad.

[0209] Please refer to Figure 9. Some embodiments of this disclosure also provide a composite material suitable for manufacturing brake pads. The composite material includes sulfide B and graphite A, and sulfide B and graphite A form a three-dimensional network structure.

[0210] Graphite A has a high melting point and good high-temperature resistance, which can remain stable in high-temperature environments. It also has natural lubricity, which can reduce noise and vibration during braking and provide a smoother braking feel. Graphite A has a low density, which can be used to manufacture lightweight brake pads, helping to improve the energy efficiency of vehicles. However, graphite A has poor thermal stability and is insufficient to cope with the high temperatures generated during braking.

[0211] During continuous braking, high temperatures can cause a decline in the performance of graphite A brake pads, and even structural damage. Sulfide B can provide a higher coefficient of friction, which helps improve the braking performance of the brake pads. However, friction pads using sulfide B alone have a relatively low thermal conductivity, affecting the stability of the coefficient of friction. When graphite A and sulfide B are used simultaneously as lubricants, they can stabilize the coefficient of friction to some extent, but the coefficient of friction will still fluctuate, and thermal fade is likely to occur.

[0212] In the three-dimensional network structure composed of sulfide B and graphite A, chemical bonds are formed between graphite A and sulfide B. The formation of these chemical bonds enhances the interfacial bonding between graphite A and sulfide B, reduces the relative sliding between them, and increases the interaction between them. This effectively transfers stress, prevents local stress concentration, and reduces defects and cracks at the micro-interface of the composite material, thereby reducing the generation and propagation of macro-cracks and improving the overall mechanical strength and wear resistance of the brake pad. The strong interfacial bonding also facilitates the effective heat transfer between graphite A and sulfide B and provides better chemical thermal stability, thus reducing heat accumulation and thermal fade in the brake pad.

[0213] The composite material provided in some embodiments of this disclosure is suitable for brake pads. The composite material comprises sulfide B and graphite A, which together form a three-dimensional network structure. Through this configuration, sulfide B and graphite A form a three-dimensional network composite material. Within this network structure, chemical bonds are formed between graphite A and sulfide B, increasing the interaction between them. This reduces the relative sliding between graphite A and sulfide B, increases heat transfer between them, and stabilizes the coefficient of friction and thermal conductivity of the composite material, making it less prone to thermal degradation. This results in a brake pad that is high-temperature resistant, friction-resistant, and has good stability.

[0214] In some embodiments, referring to FIG1, the graphite has a multilayer structure, and the sulfides satisfy at least one of the following: at least a portion of the sulfides fill the spaces between the graphite layers; or, at least a portion of the sulfides are bonded to the surface of the graphite.

[0215] A composite material with a three-dimensional network structure is formed by combining sulfide B and graphite A. The layered structure of graphite A allows it to serve as the matrix of the composite material. Small sulfide B particles are densely distributed on the surface of graphite A and between the graphite A layers, forming stable surface-to-surface contact, thus enabling the composite material to form a three-dimensional network structure. This three-dimensional network structure of the sulfide B-graphite A composite material can promote the bonding between various components in the brake pad, forming a continuous transfer film, which can improve the stability of the brake pad's friction coefficient and its wear resistance.

[0216] The multilayered structure of graphite allows sulfide particles to fill the interlayer spaces or bond to the graphite surface, thus forming a reinforced composite material. The sulfides filling the spaces between the graphite layers effectively improve the mechanical properties of the composite material. The sulfide particles act like "glue," enhancing the interlayer bonding force and improving the overall strength and abrasion resistance of the composite material.

[0217] Sulfides bonded to the surface of graphite can improve the frictional properties and thermal stability of composite materials. The adhesion of sulfide particles to the graphite surface can increase the roughness of the friction surface and may also provide additional friction mechanisms, thereby improving the braking efficiency of brake pads. The filling of sulfides can further improve thermal conductivity, quickly conduct and disperse the high temperature generated during braking, reduce thermal stress, and prevent thermal degradation of materials.

[0218] When sulfides fill the spaces between graphite layers, if the minimum distance H6 between the sulfide and graphite is less than 2 μm, the excessively small distance may hinder the sliding between graphite layers, reduce the lubricity of graphite, thereby increasing noise and vibration during braking and potentially exacerbating wear. If the sulfide particles are too dense, they may impede heat conduction, reduce the thermal conductivity of the material, and cause heat accumulation in the brake pads under high-temperature operating conditions, affecting their performance and lifespan. If the distance is too small, it may lead to uneven bonding between the sulfide particles and the graphite layers, reducing the overall strength of the composite material, resulting in unstable frictional performance of the brake pads and affecting braking effect.

[0219] When sulfides fill the spaces between graphite layers, if the minimum spacing H6 between the sulfide and graphite is greater than 8 μm, the excessive spacing between the sulfide and graphite layers will weaken the bonding force between them, leading to a decrease in the overall strength of the composite material. A larger spacing will reduce the heat conduction path, affecting the thermal conductivity of the composite material and reducing the thermal management capability of the brake pad at high temperatures. Excessive sulfide spacing will reduce the effective friction area, lower the friction coefficient of the brake pad, and affect the braking effect.

[0220] In some embodiments, the sulfide and graphite satisfy at least one of the following: when the sulfide fills between the layers of graphite, the minimum distance H6 between the sulfide and graphite satisfies: 2μm≤H6≤8μm; or, when the sulfide is bonded to the surface of graphite, the minimum distance H7 between the sulfide and graphite satisfies: 0.5μm≤H7≤10μm.

[0221] For example, the minimum distance H6 between the sulfide and graphite can be, but is not limited to, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, or 8 μm. The minimum distance H6 between the sulfide and graphite can be, but is not limited to, 0.5 μm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, or 10 μm.

[0222] When sulfides are filled between graphite layers, the minimum spacing H6 between the sulfides and graphite is within this range. The good bonding force between the sulfides and graphite can improve the overall strength of the composite material, thereby providing more stable friction performance in brake pad applications. It can also allow the graphite layers to slide relative to each other to a certain extent, maintaining the lubricating properties of graphite, reducing noise and vibration during braking, and reducing wear. Furthermore, it enhances the heat conduction path and improves the thermal conductivity of the material, which helps in the thermal management of brake pads under high-temperature operating conditions.

[0223] The minimum spacing H7 when sulfides are bonded to the surface of graphite is set for the same reason as the minimum spacing H6 between sulfides and graphite when sulfides fill the spaces between graphite sheets, and will not be repeated here.

[0224] When the mass percentage of sulfides filling the graphite layers in the composite material is less than 5%, the low sulfide content leads to insufficient bonding force between graphite layers, affecting the overall strength of the composite material, thereby reducing the friction performance and durability of the brake pads and causing a decline in braking performance; too little sulfide also affects the performance and lifespan of the brake pads under high-temperature operating conditions.

[0225] When the mass percentage of sulfides filling the spaces between graphite layers in a composite material exceeds 10%, the excessive sulfides reduce the slippage between graphite layers, thereby reducing the natural lubricity of graphite, increasing noise and vibration during braking, and aggravating wear; they also hinder heat conduction, reduce the thermal conductivity of the material, causing heat accumulation in the brake pads under high-temperature operating conditions, affecting their performance and lifespan; and they cause the composite material to become brittle, reducing the overall strength and toughness of the composite material.

[0226] In some embodiments, the sulfide and graphite satisfy at least one of the following: the sulfide filling between the graphite sheets accounts for 5%-10% of the mass of the composite material; or, the sulfide bonded to the surface of the graphite accounts for 3%-8% of the mass of the composite material.

[0227] For example, the mass percentage of sulfides filling the spaces between graphite sheets in the composite material can be, but is not limited to, 5%, 6%, 7%, 8%, 9%, or 10%. The mass percentage of sulfides bonded to the surface of graphite in the composite material can be, but is not limited to, 3%, 4%, 5%, 6%, 7%, or 8%.

[0228] Within this mass ratio, the sulfides filling the graphite layers in the composite material can enhance the bonding force between graphite layers, improve the overall strength of the composite material, and thus provide more stable friction performance in brake pad applications; increase the coefficient of friction and improve the braking effect of the brake pads, while controlling the proportion at 5%-10% can avoid excessively reducing the lubricity of graphite and maintain good wear resistance; enhance the heat conduction path and improve the thermal conductivity of the material, which helps the thermal management of brake pads under high-temperature operating conditions, while avoiding excessive sulfides from reducing thermal conductivity.

[0229] The reason for setting the mass percentage of sulfides bonded to the graphite surface in the composite material is the same as the reason for setting the mass percentage of sulfides filled between the graphite layers in the composite material, and will not be repeated here.

[0230] When the mass ratio of sulfide to graphite is less than 1:1.3, the proportion of sulfide in the composite material is too low to provide sufficient reinforcement, resulting in a decrease in the friction coefficient of the friction material layer, which affects the braking effect of the brake pads; it also leads to thermal degradation, affecting the performance of the brake pads.

[0231] When the mass ratio of sulfide to graphite is greater than 1:5, the excessive graphite proportion may not provide sufficient reinforcement, leading to a decrease in the wear resistance of the friction material layer and a shortened service life of the brake pads; it also fails to effectively improve the stability of the material at high temperatures, resulting in thermal degradation and affecting the performance of the brake pads.

[0232] In some embodiments, the mass ratio of sulfide to graphite is 1:(1.3-5). For example, the mass ratio of sulfide to graphite may be, but is not limited to, 1:1.3, 1:2, 1:3, 1:4, or 1:5.

[0233] Within this mass ratio of sulfide to graphite, the composite material exhibits good frictional properties, providing a stable coefficient of friction under various braking conditions. Its good wear resistance extends the service life of brake pads, and its high-temperature stability improves the thermal stability of the friction material layer.

[0234] In some embodiments, the sulfide includes at least one of tin sulfide, antimony sulfide, molybdenum sulfide, and ferrous sulfide.

[0235] Tin sulfide exhibits good thermal stability, enabling it to withstand high-temperature environments. It also possesses a high coefficient of friction, making it suitable for brake pads used in high-temperature applications. Antimony sulfide demonstrates good thermal stability at high temperatures and a moderate coefficient of friction, providing stable braking performance and making it suitable for various braking applications. Molybdenum sulfide possesses a high melting point and good thermal stability, maintaining structural integrity even at extreme temperatures, making it suitable for high-performance brake pads. Ferrous sulfide exhibits good thermal stability at high temperatures and a high coefficient of friction, providing excellent braking performance and making it suitable for braking systems requiring a high coefficient of friction.

[0236] For example, the sulfide can be one of tin sulfide, antimony sulfide, molybdenum sulfide, or ferrous sulfide, or it can be a binary mixture of tin sulfide and antimony sulfide, a binary mixture of tin sulfide and molybdenum sulfide, a binary mixture of tin sulfide and ferrous sulfide, a binary mixture of antimony sulfide and molybdenum sulfide, a ternary mixture of tin sulfide, antimony sulfide, molybdenum sulfide, and quaternary mixture of tin sulfide, antimony sulfide, molybdenum sulfide, and ferrous sulfide.

[0237] When the particle size D4 of the sulfide is less than 0.01 μm, the sulfide particles with too small a particle size are difficult to disperse evenly in the composite material, resulting in insufficient bonding force between them and the graphite layer, which affects the overall performance of the composite material; thus making the friction coefficient of the brake pad unstable and the thermal stability poor.

[0238] When the particle size D4 of the sulfide is greater than 10 μm, the excessively large sulfide particles are difficult to distribute uniformly in the composite material, failing to provide sufficient contact area and affecting the mechanical properties of the composite material; thus reducing the friction coefficient of the brake pad.

[0239] In some embodiments, the particle size D4 of the sulfide satisfies: 0.01 μm ≤ D4 ≤ 10 μm. For example, the particle size D4 of the sulfide can be, but is not limited to, 0.01 μm, 0.5 μm, 1 μm, 2 μm, 4 μm, 6 μm, 8 μm, or 10 μm.

[0240] When the particle size D4 of the sulfide is within this range, the sulfide particles can be uniformly dispersed and filled in the gaps between graphite layers and on the surface of graphite, forming an ideal and uniform microscopic three-dimensional network structure, which improves the overall performance of the composite material; thereby improving the friction coefficient and thermal stability of the brake pad.

[0241] When the particle size D5 of graphite is less than 500 μm, the small particle size of graphite results in a short heat conduction path, leading to a decrease in the thermal conductivity of the composite material; it also results in a smaller contact area with sulfide particles and weaker interlayer bonding force, thus affecting the overall strength and toughness of the material; consequently, the friction coefficient of the brake pad is unstable and its thermal stability at high temperatures is poor.

[0242] When the graphite particle size D5 is greater than 800μm, the excessively large graphite particle size may reduce the contact area between the interlayer and the sulfide particles, affecting the heat transfer efficiency, reducing the thermal conductivity of the material, and thus reducing the thermal stability of the brake pad at high temperatures; it also leads to uneven distribution of sulfide particles, resulting in a decrease in the friction coefficient of the composite material and affecting the braking effect of the brake pad.

[0243] In some embodiments, the particle size D5 of graphite satisfies: 500μm≤D5≤800μm. For example, the particle size D5 of graphite can be, but is not limited to, 500μm, 600μm, 700μm, or 800μm.

[0244] With a graphite particle size D5 within this range, graphite can provide a continuous thermal conduction path and allow sulfides to be uniformly dispersed and fill the voids between graphite layers, forming a uniform three-dimensional network structure, thereby improving the overall performance of the composite material; thus improving the friction coefficient and thermal stability of the brake pad.

[0245] Some embodiments of this disclosure also provide a method for preparing a composite material, as shown in Figure 10A, which includes step S30.

[0246] Step S30: Mix the sulfide and graphite to obtain the composite material.

[0247] For example, mixing sulfides and graphite yields a composite material with a three-dimensional network structure.

[0248] In some embodiments, as shown in FIG10B, in step S30, sulfide and graphite are mixed to obtain a composite material, including steps S31 to S32.

[0249] Step S31: The modifier and sulfide are mixed to obtain the modified sulfide;

[0250] Step S32: The modified sulfide and graphite form a three-dimensional network structure.

[0251] It is understandable that adding modifiers and sulfides to obtain modified sulfides allows the modified sulfide particles to be uniformly dispersed in graphite, preventing sulfide particle agglomeration and thus improving the uniformity of the composite material's performance; enhancing the bonding force between sulfide particles and graphite, improving the overall strength and toughness of the composite material; and improving the stability of sulfides at high temperatures, reducing thermal degradation, and maintaining the thermal stability of the composite material.

[0252] In some embodiments, the modifier includes at least one of sodium dodecylbenzenesulfonate, sodium dodecyl sulfate, maleic anhydride, and dodecyltrimethylammonium bromide.

[0253] Sodium dodecylbenzenesulfonate and sodium dodecyl sulfate can improve the dispersibility of sulfide particles, making them easier to disperse uniformly in graphite; maleic anhydride can react chemically with the surface of sulfide particles to form a stable bond, enhancing the bonding force between particles; dodecyltrimethylammonium bromide can adjust the frictional properties of sulfide particles and increase the coefficient of friction.

[0254] The modifier can be one of sodium dodecylbenzenesulfonate, sodium dodecyl sulfate, maleic anhydride, or dodecyltrimethylammonium bromide. Alternatively, it can be a combination of two of these three modifiers. It can also be a combination of three of these three modifiers. Finally, it can be a combination of all three of these modifiers.

[0255] Some embodiments of this disclosure also provide a brake pad comprising a friction material layer, the friction material layer comprising the composite material as described above, or a composite material prepared by the method for preparing the composite material as described above.

[0256] The friction material layer comes into contact with the brake disc or brake drum, causing the brake pads to generate friction, which slows down or stops the vehicle. The composite material provides the friction material layer with good thermal stability and wear resistance.

[0257] In some embodiments, the brake pads are suitable for vehicle braking systems, train braking systems, and aircraft braking systems.

[0258] When the thickness H8 of the brake pads is less than 4mm, the brake pads are too thin, resulting in insufficient friction during braking. This causes the brake pads to wear out faster during braking, leading to more frequent replacements and increased maintenance costs.

[0259] When the brake pad thickness H8 is greater than 6mm, due to the use of sulfide-graphite composite materials, a thicker brake pad effect can be achieved with a thinner brake pad. This excessively thick brake pad may exceed the actual braking performance required, resulting in design redundancy and increased unnecessary costs and resource consumption. The reason for setting the friction material layer thickness H9 is the same as for the brake pad thickness H8, and will not be repeated here.

[0260] In some embodiments, the brake pad and the friction material layer satisfy at least one of the following: the thickness H8 of the brake pad satisfies: 4mm≤H8≤6mm; or, the thickness H9 of the friction material layer satisfies: 3mm≤H9≤5mm.

[0261] For example, the thickness H8 of the brake pad can be, but is not limited to, 4mm, 5mm, or 6mm. The thickness H9 of the friction material layer can be, but is not limited to, 3mm, 4mm, or 5mm.

[0262] Brake pads generally consist of a steel plate, a substrate, and a friction material layer. In this embodiment, the thickness of the steel plate does not affect the performance of the brake pads in some embodiments of this disclosure. In this embodiment, the thickness of the brake pad is mainly described by the friction material layer and the substrate.

[0263] The thickness H8 of the brake pad is within this range. Since the friction material layer in some embodiments of this disclosure includes a sulfide-graphite composite material, sufficient friction can still be generated at a thinner thickness to maintain the performance of the brake pad, provide stable braking performance, and reduce costs, thereby achieving a lightweight design.

[0264] In some embodiments, the thickness H8 of the brake pad satisfies: in, satisfy: 'a' represents the mass fraction of the composite material in the friction material layer; 'x' represents the mass ratio of sulfide to graphite. For example, It can be, but is not limited to, 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, or 3mm.

[0265] Thus, by adjusting The values ​​of a and x allow for customization of brake pad thickness to suit the needs of different vehicles and braking systems. A higher percentage of composite material in the friction material layer, and a higher proportion of sulfides in the composite material, allows for the design of thicker brake pads; conversely, a lower percentage of composite material in the friction material layer, and a lower proportion of sulfides in the composite material, allows for the design of thinner brake pads.

[0266] For example, the mass fraction of composite material in the friction material layer is the value of the mass fraction of composite material in the friction material layer, which is the number of grams of composite material in 100g of friction material layer.

[0267] When 4g of composite material is present in 100g of friction material layer, the mass fraction a of composite material in friction material layer is 4; when 18g of composite material is present in 100g of friction material layer, the mass fraction a of composite material in friction material layer is 18.

[0268] When the mass fraction (a) of the composite material in the friction material layer is less than 4%, the proportion of the composite material is too low and insufficient to provide adequate reinforcement, resulting in a decrease in the wear resistance of the friction material layer, which makes the friction performance of the brake pads insufficient to meet braking requirements and weakens the thermal stability of the brake pads.

[0269] When the mass fraction (a) of composite materials in the friction material layer is greater than 18%, the excessive proportion of composite materials will lead to a decrease in the proportion of other materials in the friction material layer, resulting in excess performance, waste of resources, and an increase in overall cost.

[0270] When the mass ratio x of sulfide to graphite is less than 0.25, the proportion of sulfide in the composite material is too low to provide sufficient reinforcement, resulting in a decrease in the friction coefficient of the friction material layer, which affects the braking effect of the brake pads; it also leads to thermal degradation, affecting the performance of the brake pads.

[0271] When the mass ratio x of sulfide to graphite is greater than 0.75, the excessive graphite proportion may not provide sufficient reinforcement, leading to a decrease in the wear resistance of the friction material layer and a shortened service life of the brake pads; it also fails to effectively improve the stability of the material at high temperatures, resulting in thermal degradation and affecting the performance of the brake pads.

[0272] In some embodiments, the mass fraction 'a' of the composite material in the friction material layer satisfies: 4 ≤ a ≤ 18; the mass ratio 'x' of the sulfide to graphite satisfies: 0.2 ≤ x ≤ 0.75. For example, the mass ratio 'a' of the composite material to the friction material layer can be, but is not limited to, 4, 6, 8, 10, 12, 14, 16, or 18. The mass ratio 'x' of the sulfide to graphite can be, but is not limited to, 0.25, 0.35, 0.45, 0.55, 0.65, or 0.75.

[0273] The mass ratio x of sulfide to graphite satisfies:

[0274] When the mass fraction 'a' of the composite material in the friction material layer is within this range, and the mass fraction of the composite material in the friction material layer is appropriate, it can improve the friction performance of the brake pads, ensure a stable coefficient of friction under different braking conditions, extend the service life of the brake pads, improve the stability of the friction material layer at high temperatures, reduce thermal degradation, and maintain the performance of the brake pads.

[0275] Within this range, the mass ratio x of sulfide to graphite results in good friction performance of the composite material, providing a stable coefficient of friction under different braking conditions; the composite material also exhibits good wear resistance, extending the service life of brake pads, and has stability at high temperatures, which can improve the thermal stability of the friction material layer.

[0276] When the porosity of the friction material layer is less than 10%, the efficiency of heat conduction and diffusion is reduced, leading to heat accumulation during braking and affecting the performance and lifespan of the brake pads.

[0277] When the porosity of the friction material layer is greater than 15%, it will reduce the contact area in the friction material layer, thereby reducing the coefficient of friction and affecting the braking effect of the brake pads; it will also reduce the overall structural strength of the material, affecting the durability and reliability of the brake pads.

[0278] In some embodiments, the porosity of the friction material layer is 10%-15%. For example, the porosity of the friction material layer may be, but is not limited to, 10%, 11%, 12%, 13%, 14%, or 15%.

[0279] Within this range, the porosity of the friction material layer can improve heat conduction efficiency, allowing the heat generated by the brake pads during braking to be dissipated more effectively, reducing heat accumulation, preventing overheating, and thus improving the performance and lifespan of the brake pads.

[0280] When the density of the friction material layer is less than 2.6 g / cm³ 3 This leads to uneven material properties, causing brake pad performance to fluctuate under different conditions. It also results in poor thermal stability of the friction material layer, making it more prone to wear, thus affecting the performance of the brake pads.

[0281] When the density of the friction material layer is greater than 2.8 g / cm³ 3 When brake pads are used, their weight increases, leading to a longer braking response time and affecting braking performance.

[0282] In some embodiments, the density of the friction material layer is 2.6 g / cm³. 3 -2.8g / cm 3 For example, the density of the friction material layer can be, but is not limited to, 2.6 g / cm³. 3 2.7g / cm 3 2.8g / cm 3 .

[0283] Within this density range, the friction material layer can be guaranteed to have uniform performance, reduce performance fluctuations, and improve the stability and reliability of the brake pads; it can also improve the wear resistance and thermal stability of the friction material layer, and extend the service life of the brake pads.

[0284] In some embodiments, the friction material layer further includes an adhesive, fiber material, wear-resistant material, and filler.

[0285] Adhesives connect the components within the friction material layers, improving the overall structural strength of the brake pad. Fibers enhance the mechanical strength and toughness of the friction material layers, improving the brake pad's impact resistance. Lubricants reduce wear between the friction material layers and the brake pad, maintaining good lubrication performance. Wear-resistant materials improve the wear resistance of the friction material layers, extending the brake pad's service life. Fillers increase the density and hardness of the friction material layers, improving friction performance and wear resistance.

[0286] For example, the adhesive can be the aforementioned adhesive material that includes resin materials and filler particles, which bonds the fiber material, wear-resistant material, filler, and composite material in the brake disc together. Combining the advantages of the aforementioned adhesive material's good bonding performance at high temperatures and the composite material's stable coefficient of friction at high temperatures, brake pads with good thermal stability can be obtained.

[0287] When the adhesive accounts for less than 3% of the mass of the friction material layer, the adhesion of the components inside the friction material layer is insufficient, which cannot provide a sufficient bonding effect, resulting in internal defects in the material and affecting the overall structural strength and performance of the brake pad.

[0288] When the adhesive accounts for more than 10% of the mass of the friction material layer, the bonding performance is excessive, resulting in a waste of resources.

[0289] In some embodiments, the adhesive comprises 3-10 parts by mass of the friction material layer. For example, the adhesive may comprise, but is not limited to, 3, 4, 5, 6, 7, 8, 9, or 10 parts by mass of the friction material layer.

[0290] When the adhesive accounts for a certain percentage of the friction material layer by mass, it can enhance the adhesion between the components within the friction material layer, improve the overall structural strength of the brake pad, improve the uniformity of the friction material layer, and reduce internal defects.

[0291] When the fiber material accounts for less than 10% of the mass of the friction material layer, the low proportion of fiber material may not provide sufficient reinforcement, resulting in insufficient mechanical strength and toughness of the friction material layer, which affects the impact resistance and wear resistance of the brake pads.

[0292] When the fiber material accounts for more than 30% of the mass of the friction material layer, the excessive proportion of fiber material will lead to increased material costs. The components in the friction material layer will not be well matched, which will affect the performance of the brake pads.

[0293] In some embodiments, the fiber material accounts for 10-30% of the mass of the friction material layer. For example, the fiber material may account for, but is not limited to, 10, 15, 20, 25, or 30% of the mass of the friction material layer.

[0294] When the proportion of fiber material in the friction material layer is within this range, it can enhance the mechanical strength and toughness of the friction material layer, improve the impact resistance and wear resistance of the brake pads, improve the stability of the friction material layer at high temperatures, reduce thermal degradation, maintain the performance of the brake pads, and extend the service life of the brake pads.

[0295] When the fiber material accounts for less than 10% of the mass of the friction material layer, the low proportion of fiber material may not provide sufficient reinforcement, resulting in insufficient mechanical strength and toughness of the friction material layer, which affects the impact resistance and wear resistance of the brake pads.

[0296] When the fiber material accounts for more than 30% of the mass of the friction material layer, the excessive proportion of fiber material will lead to increased material costs. The components in the friction material layer will not be well matched, which will affect the performance of the brake pads.

[0297] In some embodiments, the wear-resistant material accounts for 10-20% of the mass of the friction material layer. For example, the wear-resistant material may account for, but is not limited to, 10, 15, or 20% of the mass of the friction material layer.

[0298] When the proportion of fiber material in the friction material layer is within this range, it can enhance the mechanical strength and toughness of the friction material layer, improve the impact resistance and wear resistance of the brake pads, improve the stability of the friction material layer at high temperatures, reduce thermal degradation, maintain the performance of the brake pads, and extend the service life of the brake pads.

[0299] When the filler accounts for less than 35% of the mass of the friction material layer, it is insufficient to improve the density and hardness of the friction material layer, affecting friction performance and wear resistance; it leads to thermal degradation, affecting the performance of the brake pads; and it reduces the wear resistance of the friction material layer, shortening the service life of the brake pads.

[0300] When the filler accounts for more than 50% of the mass of the friction material layer, the material cost will increase, the components in the friction material layer will not be compatible, and the performance of the brake pads will be affected.

[0301] In some embodiments, the filler accounts for 35-50% of the mass of the friction material layer. For example, the filler may account for, but is not limited to, 35, 40, 45, or 50% of the mass of the friction material layer.

[0302] When the filler constitutes a certain percentage of the friction material layer by mass, it can increase the density and hardness of the friction material layer, improve friction performance and wear resistance; enhance the stability of the friction material layer at high temperatures, reduce thermal degradation, and maintain the performance of the brake pads; improve the wear resistance of the friction material layer, and extend the service life of the brake pads.

[0303] For example, the mass fraction of adhesive, fiber material, wear-resistant material, and filler in the friction material layer, that is, the number of grams of adhesive, fiber material, wear-resistant material, and filler in 100g of friction material layer.

[0304] When 10g of the friction material layer contains 10g of adhesive, that is, the adhesive accounts for 10% of the mass of the friction material layer; the fiber material, wear-resistant material, and filler will not be described in detail.

[0305] In some embodiments, the adhesive includes at least one of nitrile-modified phenolic resin, low-phenol nitrile-butadiene resin, silicone rubber-modified phenolic resin, acrylate rubber-modified phenolic resin, melamine resin, epoxy resin, polyimide resin, nitrile rubber, and friction powder.

[0306] For example, the adhesive can be one of the following: nitrile-modified phenolic resin, low-phenol nitrile, silicone rubber-modified phenolic resin, acrylate rubber-modified phenolic resin, melamine resin, epoxy resin, polyimide resin, nitrile rubber, or friction powder, or a combination of multiple types, to provide different bonding properties and meet different bonding needs.

[0307] In some embodiments, the fiber material includes at least one of mineral fibers, aramid fibers, and steel fibers.

[0308] For example, the fiber material can be one of mineral fibers, aramid fibers, or steel fibers, or a combination of multiple fibers, to meet the different application requirements for different fiber materials.

[0309] In some embodiments, the wear-resistant material includes at least one of alumina, chromium oxide, ferrous chromite, magnesium oxide, silicon carbide, zirconium silicate, and zirconium oxide.

[0310] For example, wear-resistant materials can be one of the following: alumina, chromium oxide, ferrous chromite, magnesium oxide, silicon carbide, zirconium silicate, and zirconium oxide. They can also be a combination of several materials to meet the different application requirements for different wear-resistant materials.

[0311] In some embodiments, the filler includes at least one selected from iron oxide, chromite, barium sulfate, calcium carbonate, calcium hydroxide, vermiculite, mica, aluminum, tin, and zinc.

[0312] For example, the filler can be one of the following: iron(II,III) oxide, chromite, barium sulfate, calcium carbonate, calcium hydroxide, vermiculite, mica, aluminum, tin, and zinc. It can also be a combination of multiple fillers to meet the different filler requirements of various applications.

[0313] In some embodiments, referring to FIG11, the brake pad includes a substrate 8, and a friction material layer 9 is loaded on the substrate 8.

[0314] In this way, by setting the base 8, structural support can be provided for the brake pads, ensuring that the brake pads can withstand the mechanical and thermal stresses during braking and provide effective friction performance; the base can also disperse the heat generated by the friction material layer 9 during braking, thereby reducing thermal stress and improving the durability of the brake pads.

[0315] When the thickness H10 of the substrate is less than 0.5mm, it cannot provide sufficient structural stability and is prone to deformation or damage during braking, affecting the performance of the brake pads.

[0316] When the thickness H10 of the substrate is greater than 1.5mm, it cannot effectively disperse the heat generated during braking, affecting the performance of the brake pads.

[0317] In some embodiments, the thickness H5 of the substrate satisfies: 0.5mm ≤ H10 ≤ 1.5mm. For example, the thickness H10 of the substrate can be, but is not limited to, 0.5mm, 0.7mm, 0.9mm, 1.1mm, 1.3mm, or 1.5mm.

[0318] Within this range, the thickness H10 of the substrate can provide sufficient structural stability for the friction material layer, ensuring that the brake pads can withstand mechanical and thermal stresses during braking; it also helps to disperse the heat generated during braking, improve thermal management capabilities, and prevent the brake pads from overheating.

[0319] When the porosity of the substrate is less than 3%, the efficiency of heat conduction and diffusion is reduced, leading to heat accumulation during braking and affecting the performance and lifespan of the brake pads.

[0320] When the porosity of the substrate is greater than 9%, it affects the braking effect of the brake pads; it also reduces the overall structural strength of the material, affecting the durability and reliability of the brake pads.

[0321] In some embodiments, the porosity of the substrate is 3%-9%. For example, the porosity of the substrate may be, but is not limited to, 3%, 4%, 5%, 6%, 7%, 8%, or 9%.

[0322] Within this range, the porosity of the substrate can improve heat conduction efficiency, allowing the heat generated by the brake pads during braking to be dissipated more effectively, reducing heat accumulation, preventing overheating, and thus improving the performance and lifespan of the brake pads.

[0323] When the density of the matrix is ​​less than 2.7 g / cm³ 3 This leads to uneven performance of the base material, causing the brake pads' performance to fluctuate under different conditions and making them more prone to wear; thus affecting the performance of the brake pads.

[0324] When the density of the substrate is greater than 2.9 g / cm³ 3 When brake pads are used, their weight increases, leading to a longer braking response time and affecting braking performance.

[0325] In some embodiments, the density of the substrate is 2.7 g / cm³. 3 -2.9g / cm 3 For example, the density of the substrate can be, but is not limited to, 2.7 g / cm³. 3 2.8g / cm 3 2.9g / cm 3 .

[0326] A substrate density within this range ensures uniform substrate performance, reduces performance fluctuations, and improves the stability and reliability of brake pads; it also enhances the wear resistance and thermal stability of the substrate, extending the service life of brake pads.

[0327] When the working friction coefficient of the brake pads is less than 0.38, they cannot provide sufficient braking force during braking.

[0328] When the working friction coefficient of the brake pads is greater than 0.46, it leads to increased wear between the brake pads, resulting in more noise and wear particles.

[0329] In some embodiments, the working friction coefficient of the brake pad is 0.38-0.46. For example, the working friction coefficient of the brake pad may be, but is not limited to, 0.38, 0.39, 0.4, 0.41, 0.42, 0.43, 0.44, 0.45, or 0.46.

[0330] The working friction coefficient of brake pads is within this range, which can ensure that the braking performance of the brake pads is relatively stable. It will not cause excessive wear or heat accumulation due to excessive friction coefficient, nor will it result in poor braking effect due to excessive friction coefficient.

[0331] When the wear amount L of the brake pads is less than 0.01mm after being tested by a brake pad friction performance testing machine, the brake pads have high requirements for friction resistance, resulting in redundant design and waste.

[0332] When the wear amount L of the brake pads exceeds 0.4mm after a test by a brake pad friction performance testing machine, the brake pads wear too quickly, the brake pad performance fluctuates, affecting the stability and reliability of the braking effect, and the service life is greatly shortened, requiring more frequent replacement of the brake pads.

[0333] In some embodiments, the wear amount L of the brake pad after one round of wear test by a brake pad friction performance testing machine satisfies 0.01mm ≤ L ≤ 0.4mm. For example, the wear amount L of the brake pad after one round of wear test by a brake pad friction performance testing machine can be, but is not limited to, 0.01mm, 0.05mm, 0.1mm, 0.15mm, 0.20mm, 0.25mm, 0.3mm, 0.35mm, or 0.4mm.

[0334] If the wear amount L of the brake pads is within this range after being tested by a brake pad friction performance testing machine, the brake pads can maintain good performance during braking, and will not affect the braking effect due to excessive wear. They can maintain stable performance during braking and extend their service life.

[0335] Some embodiments of this disclosure provide a method for manufacturing brake pads, in which a composite material is used to form a friction material layer.

[0336] By fabricating composite materials into friction material layers, the friction coefficient and thermal conductivity of the composite materials are stable and not prone to thermal degradation, thus obtaining a friction material layer that is resistant to high temperatures, friction, and has good stability.

[0337] In some embodiments, the composite material is used to form a friction material layer, comprising: mixing the composite material, adhesive, fiber material, lubricant, wear-resistant material and filler to obtain a friction material layer; and loading the friction material layer onto a substrate to obtain a brake pad.

[0338] A friction material layer is obtained by mixing composite materials, adhesives, fibers, lubricants, wear-resistant materials, and fillers. The composite material is resistant to high temperatures, friction, and has good stability. The adhesive binds the components together. The fibers enhance the mechanical strength and toughness of the friction material layer. The lubricant reduces wear. The wear-resistant material improves wear resistance. The filler increases density and hardness. The obtained friction material layer is then loaded onto a substrate to form a brake pad.

[0339] Some embodiments of this disclosure also provide a brake pad, wherein the surface of the brake pad that contacts the brake disc is the large contact surface. Please refer to Figures 12 and 13. The brake pad includes a first carbon fiber and a second carbon fiber, which are arranged in a preset orientation. At least a portion of the first carbon fiber and at least a portion of the second carbon fiber intersect on the orthographic projection of the large contact surface.

[0340] For example, brake pads include carbon fibers arranged in a predetermined orientation. Based on their orientation, carbon fibers can be divided into first carbon fibers and second carbon fibers. Therefore, in some embodiments of this disclosure, the carbon fibers have the same dimensional properties, and the distinction between first and second carbon fibers is based on fiber orientation.

[0341] For example, the first and second carbon fibers in a brake pad can be woven into a specific needle-punching fixture, where the first and second carbon fibers are arranged in a specific pattern. The woven fabric is then combined with other brake pad materials and heat-treated to obtain the brake pad.

[0342] It should be explained that the arrangement of the first carbon fiber 11 and the second carbon fiber 12 according to a preset orientation means that the carbon fibers in all parts of the brake pad follow a regular arrangement. To determine the arrangement of carbon fibers in the brake pad, in some embodiments, the brake pad can be made into multiple samples 100 of the same specifications (shape, volume and mass), and then the carbon fibers in each sample 100 have the same arrangement.

[0343] In some embodiments, the brake pad sample 100 is a cube, as shown in Figures 12 and 13. The sample 100 includes length (e.g., in the X direction), width (e.g., in the Y direction), and height (e.g., in the Z direction). For example, the angle between the first carbon fiber 11 and the long side of the sample 100 is within a preset first range, and the angle between the second carbon fiber 12 and the long side of the sample 100 is within a preset second range. The first range may be smaller than the second range, so that the orthographic projections of the first carbon fiber 11 and the second carbon fiber 12 intersect.

[0344] It is understandable that the first carbon fiber 11 is discretely distributed relative to the long side of the sample block 100, meaning that the first carbon fiber 11 is nearly parallel to the long side of the sample block 100. The second carbon fiber 12 is discretely distributed relative to the wide side of the sample block 100, meaning that the second carbon fiber 12 is nearly parallel to the wide side of the sample block 100.

[0345] In some embodiments, referring to FIG12, the inclination angle of the first carbon fiber 11 relative to the long side of the sample block 100 (e.g., the included angle α described below) is in the range of -30° to 30°, and the inclination angle of the second carbon fiber 12 relative to the wide side of the sample block 100 is in the range of -30° to 30°, that is, the inclination angle of the second carbon fiber 12 relative to the long side of the sample block 100 (e.g., the included angle β described below) is in the range of 60° to 120°.

[0346] It is understandable that the first carbon fiber 11 can be rotated clockwise relative to the long side of the sample block 100 to produce an inclination angle of 0° to 30°, or it can be rotated counterclockwise to produce an inclination angle of -30° to 0°. Therefore, the inclination angle of the first carbon fiber 11 relative to the long side of the sample block 100 is in the range of -30° to 30°. The same applies to the second carbon fiber 12, which will not be elaborated here.

[0347] In some embodiments, the brake pad further includes a third carbon fiber, which is also arranged in a predetermined orientation. The angle of inclination of the third carbon fiber relative to the long side of the sample 100 is in the range of 30° to 60° and -30° to -60°. It is understood that the angle range of the third carbon fiber is between the first carbon fiber 11 and the second carbon fiber 12.

[0348] In some embodiments, the brake pad sample 100 is a cuboid or a cylinder, and this disclosure does not limit this. However, it should be explained that regardless of the shape of the sample 100, the first carbon fiber 11 and the second carbon fiber 12 will be arranged in a predetermined orientation in the sample 100, and the orthographic projections of at least a portion of the first carbon fiber 11 and at least a portion of the second carbon fiber 12 will intersect; only the orientation of the first carbon fiber 11 and the second carbon fiber 12 is different from the relationship between the side length (or diameter) of different samples 100.

[0349] Some embodiments of this disclosure provide a high-performance brake pad with specifically oriented carbon fibers. By optimizing the distribution of the carbon fibers, they are arranged in a specific orientation within the brake pad, thereby significantly improving the thermal conductivity, toughness, friction coefficient stability, and reducing the wear rate of the brake pad. Because carbon fibers have excellent thermal conductivity, a high decomposition temperature, and extremely high specific surface area and specific strength, the prepared brake pad exhibits good thermal conductivity and impact toughness.

[0350] In some embodiments, brake pads with a specific carbon fiber distribution orientation show a 100% increase in impact strength, a 44.8% increase in thermal conductivity, and a 0.08 increase in coefficient of friction at temperatures above 200°C compared to brake pads without carbon fiber. Compared to brake pads without a specific orientation, the impact strength is increased by 50%, the thermal conductivity by 25.1%, and the coefficient of friction is increased by 0.05 at temperatures above 200°C.

[0351] In some embodiments, referring to Figures 12 and 13, in a sample 100 of a brake pad of a predetermined volume, the impact strength A of the brake pad satisfies the following relationship:

[0352] Wherein, K1 is the impact characteristic value of the brake pad, d is the average diameter of the first carbon fiber 11 and the second carbon fiber 12, L is the average length of the first carbon fiber 11 and the second carbon fiber 12, N1 is the number of the first carbon fiber 11 in the sample block 100, a is the length of the sample block 100, b is the width of the sample block 100, and c is the height of the sample block 100.

[0353] In some embodiments, the overall impact strength A of the brake pad is 5 MPa to 10 MPa. For example, the impact strength A of the brake pad can be 5 MPa, 6 MPa, 7 MPa, 8 MPa, 9 MPa, or 10 MPa. It should be explained that the overall impact strength of the brake pad can be obtained through impact strength testing. The relationship mentioned above is the strength of sample 100 calculated using sample 100. However, since the brake pad has a uniform structure, the overall impact strength of the brake pad measured should meet the impact strength calculated using sample 100.

[0354] In some embodiments, the impact characteristic value K1 is 103 to 104. For example, the impact characteristic value K1 can be 1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000, or 10000.

[0355] In some embodiments, the length a of the sample block 100 is 1mm to 5mm, the width b of the sample block 100 is 1mm to 5mm, and the height c of the sample block 100 is 1mm to 5mm. For example, the length a of the sample block 100 can be 1mm, 2mm, 3mm, 4mm, or 5mm; the width b of the sample block 100 can be 1mm, 2mm, 3mm, 4mm, or 5mm; and the height c of the sample block 100 can be 1mm, 2mm, 3mm, 4mm, or 5mm.

[0356] In some embodiments, the average diameter d of the first carbon fiber 11 and the second carbon fiber 12 is 10 μm to 30 μm. It should be explained that the first carbon fiber 11 and the second carbon fiber 12 have the same specifications, so the average diameter d of the first carbon fiber 11 and the second carbon fiber 12 can also be considered as the diameter of either carbon fiber. For example, the average diameter d of the first carbon fiber 11 and the second carbon fiber 12 can be 10 μm, 12 μm, 14 μm, 16 μm, 18 μm, 20 μm, 22 μm, 24 μm, 26 μm, 28 μm, or 30 μm.

[0357] In some embodiments, the average length L of the first carbon fiber 11 and the second carbon fiber 12 is 1 mm to 5 mm. It should be explained that the first carbon fiber 11 and the second carbon fiber 12 have the same specifications, so the average diameter d of the first carbon fiber 11 and the second carbon fiber 12 can also be considered as the diameter of either carbon fiber. For example, the average length L of the first carbon fiber 11 and the second carbon fiber 12 can be 1 mm, 2 mm, 3 mm, 4 mm, or 5 mm.

[0358] In some embodiments, the number N1 of the first carbon fiber 11 is 10 to 20. For example, the number N1 of the first carbon fiber 11 can be 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20.

[0359] In some embodiments, in a sample 100 of a brake pad with a preset volume, the thermal conductivity λ of the brake pad satisfies the following relationship:

[0360] Wherein, K2 is the thermal conductivity characteristic value of the brake pad, d is the average diameter of the first carbon fiber 11 and the second carbon fiber 12, L is the average length of the first carbon fiber 11 and the second carbon fiber 12, N2 is the number of second carbon fibers 12 in the sample block 100, a is the length of the sample block 100, b is the width of the sample block 100, and c is the height of the sample block 100.

[0361] In some embodiments, the thermal conductivity λ of the brake pad is 2 W / (K·m) to 7 W / (K·m).

[0362] For example, the thermal conductivity λ of a brake pad can be 2 W / (K·m), 3 W / (K·m), 4 W / (K·m), 5 W / (K·m), 6 W / (K·m), or 7 W / (K·m). It should be noted that the thermal conductivity λ of the brake pad is the same as the impact strength A of the brake pad mentioned above, and the overall thermal conductivity obtained from the brake pad test should meet the range of thermal conductivity calculated using sample 100.

[0363] In some embodiments, the thermal conductivity characteristic value K2 is 102 to 103. For example, the thermal conductivity characteristic value K2 can be 100, 200, 300, 400, 500, 600, 700, 800, 900, or 1000.

[0364] In some embodiments, the length a, width b, and height c of the sample 100, as well as the diameter d and length L of the carbon fiber, in the thermal conductivity formula can refer to the above embodiments, and will not be repeated here.

[0365] In some embodiments, the number N2 of the second carbon fiber 12 is 5 to 20. For example, the number N1 of the first carbon fiber 11 can be 5, 6, 8, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20.

[0366] In some embodiments, referring to Figures 12 and 13, in a sample 100 of a brake pad with a preset volume, the coefficient of friction μ of the brake pad satisfies the following relationship:

[0367] Wherein, K3 is the lateral friction characteristic value of the brake pad, K4 is the longitudinal friction characteristic value of the brake pad, d is the average diameter of the first carbon fiber 11 and the second carbon fiber 12, L is the average length of the first carbon fiber 11 and the second carbon fiber 12, N1 is the number of first carbon fibers 11 in the sample block 100, N2 is the number of second carbon fibers 12 in the sample block 100, D1 is the shortest distance between two adjacent first carbon fibers 11 in the sample block 100, D2 is the shortest distance between two adjacent second carbon fibers 12 in the sample block 100, a is the length of the sample block 100, and b is the width of the sample block 100.

[0368] In some embodiments, the coefficient of friction μ of the brake pads is 0.35-0.55.

[0369] For example, the coefficient of friction μ can be 0.35, 0.37, 0.39, 0.41, 0.43, 0.45, 0.47, 0.49, 0.51, 0.53, or 0.55. It should be explained that the coefficient of friction μ of the brake pad is the same as the impact strength A of the brake pad mentioned above, and the overall coefficient of friction obtained from the brake pad test should meet the range of the coefficient of friction calculated using sample 100.

[0370] In some embodiments, the lateral friction characteristic value K3 is 102 to 103. For example, the lateral friction characteristic value K3 can be 100, 200, 300, 400, 500, 600, 700, 800, 900, or 1000.

[0371] In some embodiments, the longitudinal friction characteristic value K4 is 102 to 103. For example, the longitudinal friction characteristic value K4 can be 100, 200, 300, 400, 500, 600, 700, 800, 900, or 1000.

[0372] In some embodiments, the length a, width b, height c of the sample 100, the diameter d and length L of the carbon fiber, and the number N1 of the first carbon fiber 11 and the number N2 of the second carbon fiber 12 in the thermal conductivity formula can refer to the above embodiments, and will not be repeated here.

[0373] In some embodiments, please refer to FIG12. On the sample block 100 provided in the above embodiment, the sample block 100 has a first edge, the included angle α between the first carbon fiber 11 and the first edge is 0° to 30°, and the included angle β between the second carbon fiber 12 and the first edge is 60° to 90°.

[0374] As shown in Figure 12, the first edge is the straight edge (i.e., the length) in the transverse direction of the sample block 100. For example, the included angle α between the first carbon fiber 11 and the first edge can be 0°, 5°, 10°, 15°, 20°, 25°, or 30°; the included angle β between the second carbon fiber 12 and the first edge can be 60°, 65°, 70°, 75°, 80°, 85°, or 90°.

[0375] It should be explained that the angle between the first carbon fiber and the first edge should be the tilt angle of the first carbon fiber relative to the first edge. Since the rotation direction includes both clockwise and counterclockwise, the measurement of the angle between the first carbon fiber and the first edge includes α1 shown at point P in Figure 12 and α2 at point Q. Both α1 and α2 are angles of 30° (assumed to be 30°) relative to the first edge. Therefore, in some embodiments, the angle α between the first carbon fiber and the first edge is -30° to 30°. Similarly, the angle β between the second carbon fiber and the first edge also has the above relationship, which will not be elaborated here.

[0376] In some embodiments, the brake pads further include a matrix material, graphite, inorganic fillers, reinforcing fibers, and organic fillers.

[0377] For example, the matrix material can be an organic polymer, including various resin materials, and can be, but is not limited to, one or more of epoxy resin, polyester resin, polyurea-formaldehyde resin, polyurethane, polyimide, and phenolic resin.

[0378] For example, the matrix material can also be the aforementioned binder material including resin material and filler particles, in order to improve the stability of the brake pads at high temperatures.

[0379] For example, graphite can include synthetic graphite and natural graphite, and natural graphite can be high-carbon flake graphite.

[0380] For example, sulfides can be added to graphite to form a three-dimensional network structure, thereby forming the aforementioned composite material, which improves the stability of the friction coefficient and wear resistance of brake pads.

[0381] For example, inorganic fillers can be inorganic salts, including sulfates, carbonates, silicates, etc. Inorganic fillers can be precipitated barium sulfate or calcium silicate whiskers.

[0382] For example, reinforcing fibers can include steel fibers and mineral fibers.

[0383] For example, organic fillers may include calcined petroleum coke.

[0384] In some embodiments, the carbon fiber content in the brake pads is 10% to 20% by weight. For example, the carbon fiber content can be 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, or 20%.

[0385] In some embodiments, the matrix material comprises 5% to 15% by weight in the brake pad. For example, the matrix material percentage can be 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, or 15%.

[0386] In some embodiments, the graphite content in the brake pads is 10% to 30% by weight. For example, the graphite content can be 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, or 30%.

[0387] In some embodiments, the inorganic filler comprises 15% to 35% by weight in the brake pad. For example, the inorganic filler percentage can be 15%, 18%, 20%, 22%, 25%, 28%, 30%, 33%, or 35%. For example, if the inorganic filler includes calcium silicate whiskers, the calcium silicate whiskers comprise 10% to 15% by weight in the brake pad. For example, the calcium silicate whisker percentage can be 10%, 11%, 12%, 13%, 14%, or 15%.

[0388] In some embodiments, the reinforcing fiber comprises 20% to 45% by weight in the brake pad. For example, the reinforcing fiber content can be 20%, 25%, 30%, 35%, 40%, or 45%.

[0389] In some embodiments, the organic filler comprises 5% to 10% by weight in the brake pads. For example, the organic filler content can be 5%, 6%, 7%, 8%, 9%, or 10%.

[0390] In some embodiments, the graphite includes synthetic graphite and high-carbon flake graphite, with synthetic graphite comprising 5% to 15% and high-carbon flake graphite comprising 5% to 15%. For example, the proportion of synthetic graphite can be 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, or 15%; and the proportion of high-carbon flake graphite can be 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, or 15%.

[0391] In some embodiments, the reinforcing fibers include steel fibers and mineral fibers, with steel fibers comprising 15% to 30% and high-carbon flakes comprising 5% to 15%. For example, the proportion of steel fibers can be 15%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, or 30%; and the proportion of high-carbon flakes can be 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, or 15%.

[0392] Some embodiments of this disclosure also provide a method for manufacturing brake pads. Please refer to Figure 14. The method includes the following steps S4 to S5.

[0393] Step S4: The first carbon fiber and the second carbon fiber are woven onto the needle-punching fixture so that multiple carbon fibers are arranged in a preset orientation.

[0394] Step S5: Place the carbon fiber from the needle-punched fixture into a mold, and obtain a brake pad after heat treatment and cooling.

[0395] In some embodiments, the method for manufacturing brake pads, as shown in Figure 15, further includes steps S40 to S60.

[0396] Step S40: Mix the matrix material, graphite, inorganic filler, reinforcing fiber and organic filler to obtain a mixture.

[0397] Step S50: The first carbon fiber and the second carbon fiber are woven onto the needle-punching fixture so that the multiple carbon fibers are arranged in a preset orientation.

[0398] Step S60: Place the mixture in a mold, place the carbon fiber on the needle-punched fixture in the mold, and obtain the brake pad after heat treatment and cooling.

[0399] In some embodiments, step S40 includes: adding steel fibers, matrix materials, and inorganic fillers to a roller mixer in proportion, and stirring for 3 to 5 minutes at a speed of 200 r / min to 300 r / min for premixing; then adding synthetic graphite, high-carbon flake graphite, mineral fibers, calcium silicate whiskers, and organic fillers (calcined petroleum coke) to the roller mixer, and stirring for 5 to 15 minutes at a speed of 400 r / min to 500 r / min to obtain a mixture.

[0400] In some embodiments, step S60 includes: pouring the mixture into a mold and spreading it out; using the needle-punching fixture from step S50 to needle the spread powder and release carbon fibers; then using a hot-pressing mold as the ejector, with the raw material at the bottom and a steel backing at the top for hot pressing, setting the hot-pressing temperature to 140°C–160°C and the pressure to 400 kg / cm². 2 ~500kg / cm 2 The curing time is 8 to 10 minutes; then the product after hot pressing is heat treated; finally, the product is machined to obtain brake pads.

[0401] In some embodiments, prior to step S50, the method further includes: subjecting the carbon fiber to nitric acid acidification. The nitric acid acidification of the carbon fiber includes diluting concentrated nitric acid to a 20% mass fraction of dilute nitric acid, immersing the glue-free chopped carbon fiber in the dilute nitric acid for 24 hours, then removing, washing, and drying to obtain the carbon fiber.

[0402] Some embodiments of this disclosure also provide a vehicle including brake pads as provided in the above embodiments.

[0403] The embodiments of this disclosure are further described below.

[0404] Example 1

[0405] This embodiment provides a brake pad, which includes a base and a friction layer. The friction layer includes a fibrous material, a friction modifying material, a filler, and a bonding material. The bonding material includes a resin material and filler particles, with at least some of the filler particles filling the resin material.

[0406] For example, in the binder material, the ceramic particles in the filler particles are made of barite, wollastonite, corundum, magnesium oxide, or silicon carbide; the rubber particles in the filler particles are made of natural rubber; and the resin material is boron-modified phenolic resin or nitrile-modified phenolic resin. The particle size D2 of the ceramic particles is 10 μm; the ceramic particles account for 25% of the mass of the binder material; the particle size D3 of the rubber particles is 40 μm; the rubber particles account for 15% of the mass of the binder material; and the particle size D1 of the resin material is 30 μm; the resin material accounts for 60% of the mass of the binder material.

[0407] In the friction layer, by volume percentage, the binder accounts for 6%, the fiber material 25%, the friction modifier 50%, and the filler 19%. The fiber material is aramid fiber, the friction modifier is graphite, stannous sulfide, and chromite powder, and the filler is vermiculite, calcium phosphate, iron oxide, zinc oxide, corundum powder, calcium silicate, silica powder, mullite, and barium sulfate. The density of the friction layer is 2.79 g / cm³. 3The porosity of the friction layer is 21%, the impact strength of the friction layer is 4.5 MPa, the Rockwell hardness of the friction layer is 85.5 HRR, and the coefficient of friction of the friction layer is 0.40.

[0408] In the brake pad, the friction layer has a first groove, a second groove, and a third groove. The projection of the third groove onto the backing plate is a semicircle with a radius of 11 mm. The thickness of the brake pad, H1, is 15 mm; the thickness of the backing plate, H2, is 5 mm; the thickness of the friction layer, H3, is 10 mm; the depth of the first and second grooves, H4, is 7 mm; the depth of the third groove, H5, is 9 mm; the radius of the arc containing the bottom surfaces of the first and second grooves is 0.3 mm; and the central angle corresponding to the arc of the friction layer is 10°.

[0409] The method for manufacturing brake pads in this embodiment includes the following steps:

[0410] (1) The resin material is dissolved in an alcohol solution at a weight ratio of 1:1 to obtain a mixed solution A.

[0411] (2) Add rubber granules to the mixed solution A, stir, dry and crush to obtain powder A.

[0412] (3) Mix powder A with ceramic particles at a mass ratio of 1:3 at 160°C, stir for 2 hours, cool, crush, and pass through a 500-mesh sieve to obtain the binder material.

[0413] (4) Mix the binder material obtained in step (3) with the fiber material, filler and friction modifier material, and mix by plowing and rake to obtain powder B.

[0414] (5) Powder B is hot-pressed at a temperature of 160°C, a pressure of 40 MPa, and a holding time of 10 min to obtain hot-pressed block A.

[0415] (6) Heat-treat and cure hot press block A. Heat at 160°C for 3 hours, then heat to 180°C and keep for 4 hours, and finally heat to 240°C and keep for 8 hours to obtain the friction layer.

[0416] (7) The friction layer is loaded onto the substrate to obtain the brake pad.

[0417] Example 2

[0418] The difference between Example 2 and Example 1 is that the particle size D2 of the ceramic particles is 5 μm, the particle size D3 of the rubber particles is 35 μm, and the particle size D1 of the resin material is 20 μm.

[0419] The method for manufacturing the brake pads in Example 2 is the same as that in Example 1.

[0420] Example 3

[0421] The difference between Example 3 and Example 1 is that the particle size D2 of the ceramic particles is 20 μm, the particle size D3 of the rubber particles is 75 μm, and the particle size D1 of the resin material is 20 μm.

[0422] The method for manufacturing the brake pads in Example 3 is the same as that in Example 1.

[0423] Example 4

[0424] The difference between Example 4 and Example 1 is that the particle size D1 of the resin material is 28 μm.

[0425] The method for manufacturing the brake pads in Example 4 is the same as that in Example 1.

[0426] Example 5

[0427] The difference between Example 5 and Example 1 is that: in the adhesive material, the mass percentage of ceramic particles is 30%; the mass percentage of rubber particles is 30%; and the mass percentage of resin material is 40%.

[0428] The method for manufacturing the brake pads in Example 5 is the same as that in Example 1.

[0429] Example 6

[0430] The difference between Example 6 and Example 1 is that: in the adhesive material, the mass percentage of ceramic particles in the adhesive material is 20%; the mass percentage of rubber particles in the adhesive material is 20%; and the mass percentage of resin material in the adhesive material is 60%.

[0431] The method for manufacturing the brake pads in Example 6 is the same as that in Example 1.

[0432] Example 7

[0433] The difference between Example 7 and Example 1 is that, in the friction layer, by volume percentage, the bonding material accounts for 5%, the fiber material accounts for 30%, the friction modifier accounts for 40%, and the filler accounts for 25%.

[0434] The method for manufacturing the brake pads in Example 7 is the same as that in Example 1.

[0435] Example 8

[0436] The difference between Example 8 and Example 1 is that, in the friction layer, by volume percentage, the bonding material accounts for 8%, the fiber material accounts for 30%, the friction modifier accounts for 40%, and the filler accounts for 22%.

[0437] The method for manufacturing the brake pads in Example 8 is the same as that in Example 1.

[0438] Comparative Example 1

[0439] The difference between Comparative Example 1 and Example 1 is that the adhesive material in Comparative Example 1 only includes resin material, and the adhesive material accounts for 5% by volume percentage of the friction layer.

[0440] The method for manufacturing the brake pads in Comparative Example 1 is the same as that in Example 1.

[0441] Comparative Example 2

[0442] The difference between Comparative Example 2 and Example 1 is that the adhesive material in Comparative Example 1 only includes resin material, and the adhesive material accounts for 8% by volume percentage of the friction layer.

[0443] The method for manufacturing the brake pads in Comparative Example 2 is the same as that in Example 1.

[0444] Comparative Example 3

[0445] The difference between Comparative Example 3 and Example 1 is that the brake pads are commercially available, and the adhesive material only includes resin material, accounting for 17% by volume percentage of the friction layer.

[0446] Comparative Example 4

[0447] The difference between Comparative Example 4 and Example 1 is that the brake pads are commercially available, and the adhesive material only includes resin material, accounting for 12% by volume percentage of the friction layer.

[0448] Test method:

[0449] (1) Density test, using Archimedes' displacement method:

[0450] 1) Weigh the brake pads in the air and record the mass as m1.

[0451] 2) Immerse the brake pads completely in water, weigh the brake pads in the water, and record the weight as m2.

[0452] 3) The buoyant force F on the brake pad in water, F = (m1 - m2) × g.

[0453] 4) Obtain the volume V of the brake pad, V = F / (ρwater × g).

[0454] 5) The density of the brake pads is ρ, ρ = m1 / V.

[0455] (2) Porosity was tested using the Archimedes drainage method:

[0456] 1) Weigh the brake pads in air, m1.

[0457] 2) Fully immerse the brake pads in water, ensuring no air bubbles adhere to the surface. Allow the brake pads to soak in water for a sufficient time to ensure the internal pores are completely filled with water. Weigh the brake pads in water and record the weight as m2.

[0458] 3) The buoyant force F on the brake pad in water, F = (m1-m2) × g.

[0459] 4) The volume of the sample is V = F / (ρwater × g).

[0460] 5) Record the dry volume V1 of the sample in air.

[0461] 6) Porosity n = (V - V1) / V.

[0462] (3) Rockwell hardness test, Rockwell hardness tester test:

[0463] 1) Apply the indenter to the sample surface and apply an initial test force to ensure good contact between the indenter and the sample surface.

[0464] 2) While maintaining the initial test force, apply the main test force to press the indenter into the material surface.

[0465] 3) After maintaining the main test force for a certain period of time, read the depth of the indenter.

[0466] 4) Remove the main test force, but keep the initial test force.

[0467] 5) Based on the indentation depth, read the hardness value using the dial or electronic display device on the machine.

[0468] (4) Impact strength test, using drop hammer test:

[0469] 1) Place the sample on the base of the testing machine.

[0470] 2) Start the testing machine and release the drop hammer. The drop hammer falls freely from the set height and impacts the sample.

[0471] 3) Record the test data and calculate the impact strength of the sample.

[0472] (5) Friction coefficient test, which was conducted using an MM3000 friction and wear testing machine:

[0473] 1) Mount the sample on the fixed base of the testing machine and mount the moving sample on the friction head. Ensure that the contact between the samples meets the test requirements.

[0474] 2) Turn on the testing machine to cause the moving sample to move relative to the stationary sample, thereby generating friction. Record the frictional force and the corresponding coefficient of friction.

[0475] 3) The friction coefficient is calculated based on the experimental data.

[0476] (6) SEM (Scanning Electron Microscope) testing

[0477] 1) Prepare the sample.

[0478] 2) Mount the prepared sample onto the SEM sample stage. Ensure the sample is stably fixed on the sample stage.

[0479] 3) Begin scanning the sample and observe the scanned image on the SEM display. Adjust the scanning parameters as needed to obtain the SEM image.

[0480] (7) EDS (Energy Dispersive Spectrometer) test

[0481] 1) Prepare the sample.

[0482] 2) Mount the prepared sample onto the SEM sample stage. Ensure the sample is stably fixed on the sample stage.

[0483] 3) Begin scanning the sample and observe the scanned image on the SEM display. Adjust the scanning parameters as needed to obtain the SEM image.

[0484] 4) Select the sample area to be analyzed by EDS using the SEM display screen.

[0485] 5) Start the EDS system and begin acquiring X-ray spectra. The EDS detector will record the X-rays emitted by the sample and analyze them based on their energy.

[0486] 6) Use EDS software to analyze the acquired spectra to determine the types and relative contents of elements in the sample.

[0487] The brake pads obtained in Examples 1-8 and Comparative Examples 1-4 were subjected to density testing, porosity testing, Rockwell hardness testing, impact strength testing, friction coefficient testing, SEM testing, and EDS testing. The results are shown in Table 1 and Figures 6-8B.

[0488] Table 1

[0489] As can be seen from the comparison of Examples 1-8 with Comparative Examples 1-4 in Table 1, when the difference in density and porosity is small in Examples 1-8, the Rockwell hardness, impact strength and friction coefficient of Examples 1-8 are all higher than those of Comparative Examples 1-4. This indicates that by filling some of the filler particles into the resin material to form a coating structure and reducing the amount of resin material, the problem of brake pad performance degradation at high temperature caused by thermal decomposition failure of the resin material at high temperature can be avoided, and the friction performance of the bonding material at high temperature can be improved.

[0490] From the SEM image in Figure 6 and the EDS analysis in Figures 7A and 7B, white filler particles can be observed in Figure 6. Figures 7A and 7B show that the resin material includes elements such as Si and Al, proving that the filler particles enter the resin material and form a coating structure that fills the resin material.

[0491] As shown in the SEM images in Figures 8A and 8B, the brake pads can still maintain their microstructure after friction, and have good friction performance at high temperatures.

[0492] Example 9

[0493] This embodiment provides a brake pad, which includes a substrate and a friction material layer. The friction material layer includes an adhesive, a fiber material, a lubricant, a wear-resistant material, a filler, and a composite material. The composite material includes sulfides and graphite, which form a three-dimensional network structure, with a sulfide to graphite mass ratio of 1:3.

[0494] For example, the sulfide is tin sulfide, the minimum spacing between the sulfide and graphite filling the graphite layers is 5 μm, accounting for 6% of the mass of the composite material; the minimum spacing between the sulfide and graphite on the surface of the bonded graphite is 6 μm, accounting for 4% of the mass of the composite material; the particle size D1 of the sulfide is 5 μm, and the particle size D2 of the graphite is 650 μm.

[0495] The binder in the friction material layer is nitrile-modified phenolic resin, the fiber material is mineral fiber, the wear-resistant material is alumina, and the fillers include iron oxide, chromite, barium sulfate, calcium carbonate, calcium hydroxide, vermiculite, and mica. By weight, the friction material layer contains 12 parts graphite-sulfide composite material, 10 parts binder, 20 parts fiber material, 20 parts wear-resistant material, and 38 parts fillers.

[0496] The brake pads are 5mm thick, the friction material layer is 4mm thick, and the base is 1mm thick.

[0497] The method for manufacturing brake pads in this embodiment includes the following steps:

[0498] (1) Prepare a mixed solution of sulfide, anhydrous ethanol and modifier, stir at a constant speed for 30 min, filter, wash with ethanol and vacuum dry to obtain the modified sulfide.

[0499] (2) The modified sulfide and layered graphite were mixed for 30 min. The mixture was placed in a high temperature environment of 700℃, and an inert gas was introduced. After calcination for 3 h, the sulfide-graphite composite material was obtained after cooling.

[0500] (3) Mix the sulfide-graphite composite material, adhesive, fiber material, lubricant, wear-resistant material and filler obtained in (2) to obtain powder A.

[0501] (4) Take 300g of powder A and place it in a press for pressing. The hot pressing temperature is 150℃, the pressure is 20MPa, the exhaust is 5 times, and the pressure is held for 15min to obtain tablet A.

[0502] (5) The tablet A is subjected to secondary curing treatment, and the temperature is increased in stages between 150℃ and 220℃ to obtain the friction material layer.

[0503] (6) The friction material layer is loaded onto the substrate to obtain the brake pad.

[0504] Example 10

[0505] The difference between Example 10 and Example 9 is that when the sulfide fills between the graphite sheets, the minimum distance between the sulfide and the graphite is 2 μm, and when the sulfide is bonded to the surface of the graphite, the minimum distance between the sulfide and the graphite is 0.5 μm.

[0506] The method for manufacturing the brake pads in Example 10 is the same as that in Example 9.

[0507] Example 11

[0508] The difference between Example 11 and Example 9 is that when the sulfide fills between the graphite sheets, the minimum distance between the sulfide and the graphite is 8 μm, and when the sulfide is bonded to the surface of the graphite, the minimum distance between the sulfide and the graphite is 10 μm.

[0509] The method for manufacturing the brake pads in Example 11 is the same as that in Example 9.

[0510] Example 12

[0511] The difference between Example 12 and Example 9 is that the sulfide filling the spaces between the graphite sheets accounts for 5% of the mass of the composite material, while the sulfide bonded to the surface of the graphite accounts for 3% of the mass of the composite material.

[0512] The method for manufacturing the brake pads in Example 12 is the same as that in Example 9.

[0513] Example 13

[0514] The difference between Example 13 and Example 9 is that the sulfide filling the spaces between the graphite sheets accounts for 10% of the mass of the composite material, while the sulfide bonded to the surface of the graphite accounts for 8% of the mass of the composite material.

[0515] The method for manufacturing the brake pads in Example 13 is the same as that in Example 9.

[0516] Example 14

[0517] The difference between Example 14 and Example 9 is that the mass ratio of sulfide to graphite is 1:1.3.

[0518] The method for manufacturing the brake pads in Example 14 is the same as that in Example 9.

[0519] Example 15

[0520] The difference between Example 15 and Example 9 is that the mass ratio of sulfide to graphite is 1:5.

[0521] The method for manufacturing the brake pads in Example 15 is the same as that in Example 9.

[0522] Example 16

[0523] The difference between Example 16 and Example 9 is that the particle size of the sulfide is 0.01 μm and the particle size of the graphite is 500 μm.

[0524] The method for manufacturing the brake pads in Example 16 is the same as that in Example 9.

[0525] Example 17

[0526] The difference between Example 17 and Example 9 is that the particle size of the sulfide is 10 μm and the particle size of the graphite is 800 μm.

[0527] The method for manufacturing the brake pads in Example 17 is the same as that in Example 9.

[0528] Example 18

[0529] The difference between Example 18 and Example 9 is that the thickness of the brake pad is 4mm; the thickness of the friction material layer is 3mm; and the thickness of the substrate is 0.5mm.

[0530] The method for manufacturing the brake pads in Example 18 is the same as that in Example 9.

[0531] Example 19

[0532] The difference between Example 19 and Example 9 is that the brake pad thickness is 6mm; the friction material layer thickness is 5mm; and the substrate thickness is 1.5mm.

[0533] The method for manufacturing the brake pads in Example 19 is the same as that in Example 9.

[0534] Example 20

[0535] The difference between Example 20 and Example 9 is that, by mass, the friction material layer contains 8 parts of graphite-sulfide composite material, 10 parts of binder, 20 parts of fiber material, 20 parts of wear-resistant material, and 42 parts of filler.

[0536] The method for manufacturing the brake pads in Example 20 is the same as that in Example 9.

[0537] Example 21

[0538] The difference between Example 21 and Example 9 is that, by mass, the friction material layer contains 10 parts of graphite-sulfide composite material, 10 parts of binder, 20 parts of fiber material, 20 parts of wear-resistant material, and 40 parts of filler.

[0539] The method for manufacturing the brake pads in Example 21 is the same as that in Example 9.

[0540] Example 22

[0541] The difference between Example 22 and Example 9 is that, by mass, the friction material layer contains 14 parts of graphite-sulfide composite material, 10 parts of binder, 20 parts of fiber material, 20 parts of wear-resistant material, and 36 parts of filler.

[0542] The method for manufacturing the brake pads in Example 22 is the same as that in Example 9.

[0543] Example 23

[0544] The difference between Example 23 and Example 9 is that, by mass, the friction material layer contains 15 parts of graphite-sulfide composite material, 10 parts of binder, 20 parts of fiber material, 20 parts of wear-resistant material, and 35 parts of filler.

[0545] The method for manufacturing the brake pads in Example 23 is the same as that in Example 9.

[0546] Comparative Example 5

[0547] The difference between Comparative Example 5 and Example 9 is that only sulfides are added when preparing the composite material, which cannot form a three-dimensional network structure.

[0548] The method for manufacturing the brake pads in Comparative Example 5 is the same as that in Example 9.

[0549] Comparative Example 6

[0550] The difference between Comparative Example 6 and Example 9 is that only graphite is added when preparing the composite material, which cannot form a three-dimensional network structure.

[0551] The method for manufacturing the brake pads in Comparative Example 6 is the same as that in Example 9.

[0552] Comparative Example 7

[0553] The difference between Comparative Example 7 and Example 9 is that a simple mixture of graphite and sulfides is added when preparing the composite material, and the simple mixture of graphite and sulfides cannot form a three-dimensional network structure.

[0554] The method for manufacturing the brake pads in Comparative Example 7 is the same as that in Example 9.

[0555] Test method:

[0556] (8) Working friction coefficient

[0557] The brake lining friction performance testing machine is used to test brake pads by applying pressure and rotational speed to a rotating brake pad. During the test, the frictional force is measured and the working friction coefficient is calculated.

[0558] (9) Maximum coefficient of friction

[0559] The brake lining friction performance testing machine was used to test and obtain the maximum working friction coefficient.

[0560] (10) Minimum coefficient of friction

[0561] The brake lining friction performance testing machine was used to test and obtain the minimum working friction coefficient.

[0562] (11) Wear amount

[0563] The brake pad friction performance testing machine tests brake pads against a rotating brake disc during the test, subjecting them to a certain number of reciprocating motions under a specific pressure. After the test, the wear of the brake pads is measured.

[0564] Density, porosity, Rockwell hardness, impact strength, and coefficient of friction were tested in Examples 9-23 and Comparative Examples 5-7.

[0565] The test results are shown in Table 2.

[0566] Table 2

[0567] Table 2 shows that, by comparing Examples 9-23 with Comparative Examples 5-7, Examples 5-7 incorporated graphite sulfide composite materials, while Comparative Example 5 only incorporated sulfide, Comparative Example 6 only incorporated graphite, and Comparative Example 7 only incorporated sulfide and graphite. The resulting examples showed lower friction coefficients and higher wear. This indicates that the composite of sulfide and graphite can significantly increase the friction coefficient and reduce wear.

[0568] By comparing Example 9 with Examples 10-23, the working friction coefficient, maximum friction coefficient and minimum friction coefficient of Example 9 are higher than those of Examples 10-15; the composite material with 12 parts of sulfide and graphite can significantly increase the high-temperature friction coefficient and reduce the amount of wear.

[0569] In Examples 10 and 11, 8-10 parts of a sulfide and graphite composite were added, resulting in slightly higher wear. In Examples 12 and 13, 14-15 parts of a sulfide and graphite composite were added, resulting in more solid lubricant. Although the wear was lower, the overall coefficient of friction was not high.

[0570] Example 24

[0571] The brake pads provided in this embodiment include phenolic resin (6%), synthetic graphite (12%), high-carbon flake graphite (5%), precipitated barium sulfate (10%), carbon fiber (15%), calcium silicate whiskers (12%), steel fiber (20%), calcined petroleum coke (10%), and mineral fiber (10%).

[0572] For example, the carbon fiber includes a first carbon fiber and a second carbon fiber. The diameter d of the carbon fiber is 20 μm, the length L of the carbon fiber is 2.5 mm, the included angle α of the first carbon fiber is 15°, the included angle β of the second carbon fiber is 75°, the shortest distance D1 between two adjacent first carbon fibers is 25 μm, and the shortest distance D2 between two adjacent second carbon fibers is 25 μm.

[0573] In the sample block (length a = 2.5 mm, width b = 2.5 mm, height c = 2.5 mm), the number of first carbon fibers N1 is 15 and the number of second carbon fibers N2 is 10.

[0574] The method for manufacturing brake pads in this embodiment includes the following steps:

[0575] 1) Phenolic resin, synthetic graphite, high-carbon flake graphite, precipitated barium sulfate, calcium silicate whiskers, steel fiber, calcined petroleum coke, and mineral fiber are mixed evenly according to the formula ratio to obtain a mixture.

[0576] 2) The carbon fibers with well-dispersed monofilaments are woven onto a specific needle-punching fixture.

[0577] 3) Pour the mixture into a mold, use a needle punch to puncture the flattened powder, and release carbon fibers. Brake pads are then produced through pressing, curing, and demolding processes.

[0578] Example 25

[0579] The brake pads provided in this embodiment include phenolic resin, synthetic graphite, high-carbon flake graphite, precipitated barium sulfate, carbon fiber, calcium silicate whiskers, steel fiber, calcined petroleum coke, and mineral fiber.

[0580] The difference between this embodiment and embodiment 24 is that the diameter of the carbon fiber is 10 μm and the length of the carbon fiber is 1 mm.

[0581] Example 26

[0582] The brake pads provided in this embodiment include phenolic resin, synthetic graphite, high-carbon flake graphite, precipitated barium sulfate, carbon fiber, calcium silicate whiskers, steel fiber, calcined petroleum coke, and mineral fiber.

[0583] The difference between this embodiment and embodiment 24 is that the diameter of the carbon fiber is 30μm and the length of the carbon fiber is 5mm.

[0584] Example 27

[0585] The brake pads provided in this embodiment include phenolic resin, synthetic graphite, high-carbon flake graphite, precipitated barium sulfate, carbon fiber, calcium silicate whiskers, steel fiber, calcined petroleum coke, and mineral fiber.

[0586] The difference between this embodiment and embodiment 24 is that the included angle α of the first carbon fiber is 30° and the included angle β of the second carbon fiber is 60°.

[0587] Example 28

[0588] The brake pads provided in this embodiment include phenolic resin, synthetic graphite, high-carbon flake graphite, precipitated barium sulfate, carbon fiber, calcium silicate whiskers, steel fiber, calcined petroleum coke, and mineral fiber.

[0589] The difference between this embodiment and embodiment 24 is that the included angle α of the first carbon fiber is 0° and the included angle β of the second carbon fiber is 90°.

[0590] Example 29

[0591] The brake pads provided in this embodiment include phenolic resin, synthetic graphite, high-carbon flake graphite, precipitated barium sulfate, carbon fiber, calcium silicate whiskers, steel fiber, calcined petroleum coke, and mineral fiber.

[0592] The difference between this embodiment and embodiment 24 is that the shortest distance between two adjacent first carbon fibers is 10 μm, and the shortest distance between two adjacent second carbon fibers is 10 μm.

[0593] Example 30

[0594] The brake pads provided in this embodiment include phenolic resin, synthetic graphite, high-carbon flake graphite, precipitated barium sulfate, carbon fiber, calcium silicate whiskers, steel fiber, calcined petroleum coke, and mineral fiber.

[0595] The difference between this embodiment and embodiment 24 is that the shortest distance between two adjacent first carbon fibers is 50 μm, and the shortest distance between two adjacent second carbon fibers is 50 μm.

[0596] Example 31

[0597] The brake pads provided in this embodiment include phenolic resin, synthetic graphite, high-carbon flake graphite, precipitated barium sulfate, carbon fiber, calcium silicate whiskers, steel fiber, calcined petroleum coke, and mineral fiber.

[0598] The difference between this embodiment and embodiment 24 is that the number of first carbon fibers N1 is 10 and the number of second carbon fibers N2 is 5.

[0599] Example 32

[0600] The brake pads provided in this embodiment include phenolic resin, synthetic graphite, high-carbon flake graphite, precipitated barium sulfate, carbon fiber, calcium silicate whiskers, steel fiber, calcined petroleum coke, and mineral fiber.

[0601] The difference between this embodiment and embodiment 24 is that the number of the first carbon fiber N1 is 20 and the number of the second carbon fiber N2 is 20.

[0602] Example 33

[0603] The brake pads provided in this embodiment include phenolic resin, synthetic graphite, high-carbon flake graphite, precipitated barium sulfate, carbon fiber, calcium silicate whiskers, steel fiber, calcined petroleum coke, and mineral fiber.

[0604] The difference between this embodiment and embodiment 24 is that the phenolic resin (6%), synthetic graphite (12%), high-carbon flake graphite (5%), precipitated barium sulfate (15%), carbon fiber (10%), calcium silicate whiskers (12%), steel fiber (20%), calcined petroleum coke (10%), and mineral fiber (10%) are used.

[0605] Example 34

[0606] The brake pads provided in this embodiment include phenolic resin, synthetic graphite, high-carbon flake graphite, precipitated barium sulfate, carbon fiber, calcium silicate whiskers, steel fiber, calcined petroleum coke, and mineral fiber.

[0607] The difference between this embodiment and embodiment 24 is that the phenolic resin (6%), synthetic graphite (12%), high-carbon flake graphite (5%), precipitated barium sulfate (5%), carbon fiber (20%), calcium silicate whiskers (12%), steel fiber (20%), calcined petroleum coke (10%), and mineral fiber (10%) are used.

[0608] Example 35

[0609] The brake pads provided in this embodiment include phenolic resin, synthetic graphite, high-carbon flake graphite, carbon fiber, precipitated barium sulfate, calcium silicate whiskers, steel fiber, calcined petroleum coke, and mineral fiber.

[0610] The difference between this embodiment and embodiment 24 is that the phenolic resin (6%), synthetic graphite (12%), high-carbon flake graphite (5%), precipitated barium sulfate (20%), carbon fiber (5%), calcium silicate whiskers (12%), steel fiber (20%), calcined petroleum coke (10%), and mineral fiber (10%) are used.

[0611] Comparative Example 8

[0612] The brake pads provided in this comparative example include phenolic resin, synthetic graphite, high-carbon flake graphite, precipitated barium sulfate, calcium silicate whiskers, steel fibers, calcined petroleum coke, and mineral fibers.

[0613] The difference between this comparative example and Example 24 is that the brake pads do not contain carbon fiber. For example, phenolic resin (6%), synthetic graphite (12%), high-carbon flake graphite (5%), precipitated barium sulfate (25%), calcium silicate whiskers (12%), steel fiber (20%), calcined petroleum coke (10%), and mineral fiber (10%).

[0614] Comparative Example 9

[0615] The brake pads provided in this comparative example include phenolic resin, synthetic graphite, high-carbon flake graphite, precipitated barium sulfate, carbon fiber, calcium silicate whiskers, steel fiber, calcined petroleum coke, and mineral fiber.

[0616] The difference between this comparative example and Example 24 is that the carbon fibers in the brake pads are randomly arranged.

[0617] The brake pads obtained in Examples 24-35 and Comparative Examples 8-9 were subjected to the following tests:

[0618] Impact strength test: The impact strength was determined according to the national standard GB / T 1043.1-2008, the national standard for testing the impact strength of plastics.

[0619] Thermal conductivity test: The test method for thermal conductivity of refractory materials (parallel hot wire method) is adopted according to the national standard GB / T 17106-1997.

[0620] Friction and wear test: The coefficient of friction and wear rate were determined according to the national standard GB5763-2008 "Automotive Brake Liners".

[0621] The test results are shown in Tables 3-5.

[0622] Table 3

[0623] Table 4

[0624] Table 5

[0625] As can be seen from the test results of the brake pads in Examples 24-35 and Comparative Examples 8-9 in Tables 3-5, the impact strength, thermal conductivity, and coefficient of friction of brake pads with carbon fibers of a specific distribution orientation are significantly improved compared to those without carbon fibers. Compared to brake pads without a specific orientation, the impact strength, thermal conductivity, and coefficient of friction are all improved when the specific orientation of the carbon fibers is met. Therefore, it is demonstrated that the brake pads provided by some embodiments of this disclosure have higher physical properties than brake pads in related technologies.

[0626] In the description of the embodiments of this disclosure, it should be noted that the orientation or positional relationship of the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and other indicators are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this disclosure and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this disclosure.

[0627] The above-disclosed embodiments are merely preferred embodiments of this disclosure and should not be construed as limiting the scope of this disclosure. Those skilled in the art will understand that all or part of the processes for implementing the above embodiments, and equivalent variations made in accordance with the claims of this disclosure, still fall within the scope of this disclosure.

Claims

1. An adhesive material suitable for brake pads; said adhesive material comprising a resin material and filler particles, wherein at least a portion of said filler particles are filled in the resin material.

2. The cementitious material of claim 1, wherein, The resin material accounts for 40%-60% of the mass of the adhesive material.

3. The binding material of claim 1 or 2, wherein, The particle size D1 of the resin material satisfies: 20μm≤D1≤50μm.

4. The binding material of any one of claims 1 to 3, wherein, The resin material includes at least one of boron-modified phenolic resin, nitrile-modified phenolic resin, cashew nut shell liquid-modified phenolic resin, and silicone rubber-modified phenolic resin.

5. The adhesive material according to any one of claims 1 to 4, wherein, The filler particles include ceramic particles, and the particle size D2 of the ceramic particles satisfies: 5μm≤D2≤20μm.

6. The adhesive material according to claim 5, wherein, The ceramic particles comprise 20%-30% of the mass of the adhesive material.

7. The adhesive material according to claim 5 or 6, wherein, The ceramic particles include at least one of the following: feldspar, barite, iron oxide, diatomite, wollastonite, chromite, sulfides, zircon, corundum, cryolite, magnesium oxide, zinc oxide, barium sulfate, silicon carbide, copper oxide, iron powder, copper powder, aluminum powder, and magnesite.

8. The adhesive material according to any one of claims 1 to 7, wherein, The filler particles also include rubber particles, the particle size D3 of which satisfies: 35μm≤D3≤75μm.

9. The adhesive material according to claim 8, wherein, The rubber particles constitute 20%-30% of the mass of the adhesive material.

10. The adhesive material according to claim 8 or 9, wherein, The rubber particles include at least one of styrene-butadiene rubber, tire powder, nitrile rubber, ethylene propylene rubber, asphalt, natural rubber, cashew nut shell oil friction powder, and amino ester powder.

11. A method for preparing an adhesive material, comprising: Provide resin materials and filler particles; as well as At least a portion of the filler particles are filled into the resin material.

12. A brake pad comprising a friction layer, the friction layer comprising: The adhesive material according to any one of claims 1-10, or the adhesive material obtained by the preparation method of the adhesive material according to claim 11.

13. The brake pad according to claim 12, wherein, The friction layer also includes fiber material, friction-modifying material, and filler.

14. The brake pad according to claim 13, wherein, Based on the volume percentage of the friction layer, the fiber material accounts for 20%-30%; the friction-modifying material accounts for 40%-60%; and the filler accounts for 15%-35%. The adhesive material accounts for 5%-8%.

15. The brake pad according to claim 13 or 14, wherein, The fiber material includes at least one of aramid fiber, ceramic fiber, composite mineral fiber, carbon fiber, and brass fiber.

16. The brake pad according to any one of claims 13 to 15, wherein, The friction-modifying material includes friction-reducing materials and friction-enhancing materials. The friction-reducing materials include at least one of graphite or metal sulfides, and the friction-enhancing materials include at least one of chromite powder, zircon powder, alumina, magnesium oxide, wollastonite, cryolite, carbon black, and silicon carbide.

17. The brake pad according to any one of claims 13 to 16, wherein, The filler includes at least one of the following: vermiculite, mica powder, calcium oxide, titanium dioxide, calcium phosphate, zinc sulfate, iron oxide, zinc oxide, feldspar powder, corundum powder, bentonite, calcium silicate, potassium titanate, silicon dioxide, iron powder, copper powder, silicon powder, mullite, and barium sulfate.

18. The brake pad according to any one of claims 12 to 17, wherein, The friction layer satisfies at least one of the following: The density of the friction layer is 2.8 g / cm 3 -2.9 g / cm 3 ; The porosity of the friction layer is 20%-22%; The impact strength of the friction layer is 4.0 MPa-5.0 MPa; The Rockwell hardness of the friction layer is 75 HRR-90 HRR; or... The friction coefficient of the friction layer is 0.35-0.

45.

19. The brake pad according to any one of claims 12 to 18, wherein, The brake pad also includes a back plate, and the friction layer is connected to the back plate; a first groove and a second groove are formed on the friction layer; the first groove and the second groove are adapted to guide airflow to improve the braking effect of the brake pad.

20. The brake pad according to claim 19, wherein, A third groove is also provided on the friction layer; the third groove is suitable for installing an alarm device to monitor the thickness of the friction layer.

21. The brake pad according to claim 20, wherein, The projection shape of the third groove on the back plate is a semicircle, and the radius of the semicircle is 10mm-12mm.

22. The brake pad according to claim 20 or 21, wherein, The thickness H1 of the brake pad is 14mm-16mm; The thickness H2 of the back plate is 4.5mm-5.5mm; The thickness H3 of the friction layer is 8mm-10mm; The depth H4 of the first and second tanks is 6mm-8mm; The depth H5 of the third groove is 8mm-10mm; The bottom surfaces of the first and second grooves are arc surfaces, and the radius of the arc surface is 0.2mm-0.5mm.

23. The brake pad according to any one of claims 19 to 22, wherein, One side of the friction layer is an arc, and the central angle corresponding to the arc is 5°-20°.

24. A method for manufacturing brake pads, for manufacturing brake pads according to any one of claims 12-23, the method comprising: The adhesive material is prepared as a friction layer; as well as The friction layer is then used to manufacture brake pads.

25. The method for manufacturing brake pads according to claim 24, wherein, The step of preparing the adhesive material into the friction layer includes: The friction layer is obtained by mixing fiber material, friction modifier, filler and binder. The step of fabricating the friction layer into the brake pad includes: The friction layer is disposed on the back plate to obtain the brake pad.

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