A friction pad that is friendly to braking pairs and its preparation method

Abstract

This invention provides a brake mating-friendly friction pad, comprising the following components in parts by weight: 10-15 parts phenolic resin, 4-8 parts acrylic fiber, 20-30 parts mortise and tenon joints, 6-10 parts mineral fiber, 20-45 parts barium sulfate, 1-3 parts iron black, 2-4 parts ultra-fine high-graphite, 3-6 parts coke powder, 3-8 parts calcium hydroxide, and 1-2 parts aramid fiber. This invention introduces mortise and tenon joints into the formula, increasing the friction pad's compressibility and providing a buffering effect during braking. This improves the point-to-point contact between the friction pad and the brake mating device, reduces the probability of localized high temperatures, optimizes the cracking and grooving problems of the brake mating device under harsh conditions, extends the service life of the brake mating device, and improves vehicle safety under harsh conditions.

Description

Technical Field

[0001] This invention relates to the field of friction materials technology, specifically to a friction pad that is friendly to braking mating and its preparation method. Background Technology

[0002] As a key safety component of automotive braking systems, friction pads have mature technical solutions in terms of braking safety and wear resistance. There has also been some theoretical research on noise optimization and brake dust accumulation. However, research on the protection of brake pads is insufficient. Through experiments and research, it has been found that the cracking and grooves of brake pads are not only related to their own material but also to the material of the friction pads.

[0003] With the widespread use of bimetallic brake mating materials, due to the special properties of the material, the failure modes of grooves and cracks have increased under special working conditions, posing certain dangers to vehicle operation. The cost of the brake drum itself and the labor costs are relatively high. Therefore, a formula and process are needed to comprehensively optimize the aggression of the friction pads on the brake mating material, improve the service life of the brake mating material, and improve vehicle driving safety. Summary of the Invention

[0004] The purpose of this invention is to overcome the defects of the prior art and provide a friction pad that is friendly to the braking couple and its preparation method, optimize the friction pad's aggression against the braking couple, and ensure that the braking couple can be used normally under harsh working conditions.

[0005] This invention is implemented as follows:

[0006] This invention provides a friction pad that is friendly to braking mating, comprising the following components in parts by weight: 10-15 parts phenolic resin, 4-8 parts acrylic fiber, 20-30 parts mortise and tenon particles, 6-10 parts mineral fiber, 20-45 parts barium sulfate, 1-3 parts iron black, 2-4 parts ultra-fine high-graphite, 3-6 parts coke powder, 3-8 parts calcium hydroxide, and 1-2 parts aramid fiber.

[0007] Ordinary brake drums / discs are made of HT250 cast iron. At 0-600℃, they are lamellar pearlite with a hardness of HB200-220. At 600℃-700℃, they are granular pearlite + austenitic dendrites with a hardness of HB150-200. At the same time, the longer the temperature in this stage lasts, the more obvious the changes in metallography and hardness become.

[0008] During braking in typical plains conditions, the vehicle system temperature is around 200℃, while in mountainous areas it is around 350℃. The temperature varies depending on the frequency of braking. Although the measured temperature did not reach over 600℃, the vehicle testing system only measures the average temperature of the entire braking system (mainly referring to the friction pads and brake mats), and cannot detect the local temperature of the braking system. During each braking action, the friction pads and brake mats are in full contact macroscopically, but microscopically, due to surface runout and roughness, the actual contact area is small. The friction pads and brake mats experience greater local pressure and higher local temperatures. Tests show that the instantaneous local temperature can reach 1000℃. Under such conditions, the local metallographic structure and hardness of the brake mats change. During repeated braking, cracks and grooves are prone to occur at the locations where these changes occur.

[0009] The intensive particles introduced in this invention are flexible particles with a certain degree of elasticity. Adding them to friction materials can increase the compression ratio of the friction pads, play a buffering role during braking, improve the point-to-point contact between the friction pads and the braking pair, and reduce the probability of local high temperature.

[0010] Furthermore, the internally mixed particles comprise the following components in parts by weight: 10-15 parts solid nitrile rubber, 8-10 parts phenolic resin, 0.5-1 parts vulcanization system, 30-50 parts flake graphite, 10-15 parts hemp fiber, and 10-20 parts barium sulfate, wherein the vulcanization system comprises sulfur, NOBS accelerator, and zinc oxide, and the mass ratio of sulfur, NOBS accelerator, and zinc oxide is 2:2:1.

[0011] Furthermore, the iron black is 800-1000 mesh, the barium sulfate is less than 200 mesh, the coke powder is less than 300 mesh, the calcium hydroxide is 300-500 mesh, and the pulverized particles are 100-200 mesh.

[0012] Furthermore, the length of the acrylic fiber is 2-5 mm.

[0013] Furthermore, the thickness of the acrylic fiber is 0.1-0.3 mm.

[0014] Furthermore, the length of the aramid fiber is 5-9 mm.

[0015] Furthermore, the thickness of the aramid fiber is 0.1-0.3 mm.

[0016] The present invention also provides a method for preparing the above-mentioned brake mating-friendly friction pad, comprising the following steps:

[0017] S1. Weigh the raw materials according to the proportions and mix them to obtain a mixture;

[0018] S2. The mixture is hot-pressed and cured to obtain the braking mating-friendly friction pad.

[0019] In step S2, the hot pressing pressure is 160-180 MPa and the curing time is 8-12 min.

[0020] The present invention has the following beneficial effects:

[0021] 1. The formulation of this invention optimizes the cracking problem of braking couples under harsh conditions and extends the service life of braking couples;

[0022] 2. The formulation of this invention optimizes the groove problem under harsh conditions of the braking couple and extends the service life of the braking couple;

[0023] 3. The formulation of this invention optimizes the protective effect of the friction pads on the braking pair, thereby improving vehicle safety under harsh conditions. Detailed Implementation

[0024] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0025] Example 1

[0026] The preparation method of the friction pad in this embodiment is as follows: the raw materials are weighed according to the ratio, mixed and placed in a thermosetting mold, cured under a pressure of 160MPa for 10 minutes, and then the finished friction pad is obtained after subsequent grinding.

[0027] The raw material ratio is as follows: 15 parts phenolic resin, 8 parts acrylic fiber, 20 parts granules, 10 parts mineral fiber, 24 parts barium sulfate, 3 parts iron black, 4 parts high-density graphite, 6 parts coke powder, 8 parts calcium hydroxide, and 2 parts aramid fiber.

[0028] The internally mixed particles consist of 10 parts solid nitrile rubber, 8 parts phenolic resin, 1 part vulcanization system, 46 parts flake graphite, 15 parts hemp fiber, and 20 parts barium sulfate.

[0029] The friction performance of the friction pads was tested according to standard GB5763-2018, and the results are shown in Table 1:

[0030] Table 1. Friction properties of the friction plates prepared in Example 1

[0031]

[0032] The friction plates were tested using the standard SAE-J3080, and the number of times the braking pair cracked was 150.

[0033] Example 2

[0034] The preparation method of the friction pad in this embodiment is as follows: the raw materials are weighed according to the ratio, mixed and placed in a thermosetting mold, cured under a pressure of 160MPa for 8 minutes, and the finished friction pad is obtained after drilling.

[0035] The raw material ratio is as follows: 13 parts phenolic resin, 6 parts acrylic fiber, 22 parts granules, 10 parts mineral fiber, 24 parts barium sulfate, 4 parts iron black, 5 parts high-density graphite, 7 parts coke powder, 7 parts calcium hydroxide, and 2 parts aramid fiber.

[0036] The internally mixed particles consist of 12 parts solid nitrile rubber, 10 parts phenolic resin, 1 part vulcanization system, 44 parts flake graphite, 15 parts hemp fiber, and 18 parts barium sulfate.

[0037] The friction performance of the friction pads was tested according to standard GB5763-2018, and the results are shown in Table 2:

[0038] Table 2. Friction properties of the friction plates prepared in Example 2

[0039]

[0040]

[0041] The friction plates were tested using the standard SAE-J3080, and the number of times the braking pair cracked was 160.

[0042] Example 3

[0043] The preparation method of the friction pad in this embodiment is as follows: the raw materials are weighed according to the ratio, mixed and placed in a thermosetting mold, cured under a pressure of 160MPa for 8 minutes, and the finished friction pad is obtained after drilling.

[0044] The raw material ratio is as follows: 12 parts phenolic resin, 5 parts acrylic fiber, 23 parts granulated granules, 8 parts mineral fiber, 23 parts barium sulfate, 5 parts iron black, 6 parts high-density graphite, 6 parts coke powder, 6 parts calcium hydroxide, and 2 parts aramid fiber.

[0045] The internally mixed particles consist of 11 parts solid nitrile rubber, 9 parts phenolic resin, 0.5 parts vulcanization system, 46 parts flake graphite, 14 parts hemp fiber, and 19 parts barium sulfate.

[0046] The friction performance of the friction pads was tested according to standard GB5763-2018, and the results are shown in Table 3:

[0047] Table 3. Friction properties of the friction plates prepared in Example 3

[0048]

[0049] The friction plates were tested using the standard SAE-J3080, and the number of times the braking pair cracked was 170.

[0050] Comparative Example 1

[0051] The preparation method of the friction pad in this embodiment is as follows: the raw materials are weighed according to the ratio, mixed and placed in a thermosetting mold, cured under a pressure of 160MPa for 8 minutes, and the finished friction pad is obtained after drilling.

[0052] The raw materials are formulated as follows: 15 parts phenolic resin, 8 parts acrylic fiber, 5 parts nitrile rubber, 15 parts friction particles, 10 parts mineral fiber, 24 parts barium sulfate, 3 parts iron black, 4 parts high-density graphite, 6 parts coke powder, 8 parts calcium hydroxide, and 2 parts aramid fiber.

[0053] The friction performance of the friction pads was tested according to standard GB5763-2018, and the results are shown in Table 4:

[0054] Table 4 shows the friction properties of the friction plates prepared in Comparative Example 1.

[0055]

[0056] The friction plates were tested using the standard SAE-J3080, and the braking pair cracked 90 times.

[0057] Comparative Example 2

[0058] The preparation method of the friction pad in this embodiment is as follows: the raw materials are weighed according to the ratio, mixed and placed in a thermosetting mold, cured under a pressure of 160MPa for 8 minutes, and the finished friction pad is obtained after drilling.

[0059] The raw material ratio is as follows: 13 parts phenolic resin, 6 parts acrylic fiber, 6 parts nitrile rubber, 16 parts friction particles, 10 parts mineral fiber, 24 parts barium sulfate, 4 parts iron black, 5 parts high-density graphite, 7 parts coke powder, 7 parts calcium hydroxide, and 2 parts aramid fiber.

[0060] The friction performance of the friction pads was tested according to standard GB5763-2018, and the results are shown in Table 5:

[0061] Table 5. Friction properties of the friction plates prepared in Comparative Example 2

[0062]

[0063] The friction plates were tested using the standard SAE-J3080, and the number of times the braking pair cracked was 100.

[0064] Comparative Example 3

[0065] The preparation method of the friction pad in this embodiment is as follows: the raw materials are weighed according to the ratio, mixed and placed in a thermosetting mold, cured under a pressure of 160MPa for 8 minutes, and the finished friction pad is obtained after drilling.

[0066] The raw material ratio is as follows: 12 parts phenolic resin, 5 parts acrylic fiber, 6 parts nitrile rubber, 17 parts friction particles, 8 parts mineral fiber, 23 parts barium sulfate, 5 parts iron black, 6 parts high-density graphite, 6 parts coke powder, 6 parts calcium hydroxide, and 2 parts aramid fiber.

[0067] The friction performance of the friction pads was tested according to standard GB5763-2018, and the results are shown in Table 6:

[0068] Table 6. Friction properties of the friction plates prepared in Comparative Example 3

[0069]

[0070] The friction plates were tested using the standard SAE-J3080, and the number of times the braking pair cracked was 110.

[0071] From the comparison between Examples 1-3 and Comparative Examples 1-3, it can be seen that after introducing the intensively mixed particles into the raw material system of the formulations in the examples, the friction performance of the prepared friction plates is not much different from that of the comparative examples, but the number of cracks in the braking couple is significantly increased. Compared with friction particles, the intensively mixed particles can increase the compression ratio of the friction plate, play a buffering role in the braking process, improve the point-to-point contact between the friction plate and the braking couple, reduce the probability of local high temperature, and optimize the cracking and grooving problems of the braking couple under harsh conditions. This shows that the friction plates prepared by introducing the intensively mixed particles in Examples 1-3 have optimized the protective effect of the friction plate on the braking couple and improved the service life of the braking couple.

[0072] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A friction pad that is friendly to braking pairs, characterized in that, It includes the following components in parts by weight: 12-15 parts phenolic resin, 5-8 parts acrylic fiber, 20-23 parts intensively mixed particles, 8-10 parts mineral fiber, 23-24 parts barium sulfate, 1-3 parts iron black, 2-4 parts extra-fine high-graphite, 3-6 parts coke powder, 6-8 parts calcium hydroxide, and 1-2 parts aramid fiber. The intensively mixed particles comprise the following components by weight: 10-12 parts solid nitrile rubber, 8-10 parts phenolic resin, 0.5-1 parts vulcanization system, 44-46 parts flake graphite, 14-15 parts hemp fiber, and 18-20 parts barium sulfate, wherein the vulcanization system comprises sulfur, accelerator, and zinc oxide, and the ratio of sulfur, accelerator, and zinc oxide is 2:2:

1. The iron black is 800-1000 mesh, barium sulfate is less than 200 mesh, coke powder is less than 300 mesh, calcium hydroxide is 300-500 mesh, and the pulverized particles are 100-200 mesh. The acrylic fiber has a length of 2-5 mm; The thickness of the acrylic fiber is 0.1-0.3 mm; The length of the aramid fiber is 5-9 mm; The thickness of the aramid fiber is 0.1-0.3 mm; The method for preparing the braking mating-friendly friction pad includes the following steps: S1. Weigh the raw materials according to the proportions and mix them to obtain a mixture; S2. The mixture is hot-pressed and cured to obtain the braking mating-friendly friction pad; In step S2, the hot pressing pressure is 160-180 MPa, and the curing time is 8-12 min.

2. The method for preparing the braking mating-friendly friction pad according to claim 1, characterized in that: Includes the following steps: S1. Weigh the raw materials according to the proportions and mix them to obtain a mixture; S2. The mixture is hot-pressed and cured to obtain the braking mating-friendly friction pad; In step S2, the hot pressing pressure is 160-180 MPa, and the curing time is 8-12 min.

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