Organic ceramic brake pad for road vehicle carbon ceramic brake disc and preparation method thereof

Abstract

The present application relates to a kind of road vehicle carbon ceramic brake disc with organic ceramic brake pad and its preparation method, raw material includes the following components by weight percentage: phenolic resin 1~4%, boron modified phenolic resin 1~5%, aluminum metaphosphate 4~15%, sodium silicate 3~7%, ammonium fluoride 1~3%, magnesium oxide 1~5%, copper oxide 3~5%, aluminum powder 2~6%, carbon fiber 1~6%, aramid pulp 1~6%, steel fiber 8~15%, reduced iron powder 15~20%, red copper powder 6~12%, antimony oxide 1~3%, zinc borate 5~8%, diantimony trisulfide 2~6%, molybdenum disulfide 4~6%, calcined petroleum coke 5~8%, aluminum titanate 1~5%, titanium oxide 1~4%, zirconium oxide 5~12%, silicon carbide 4~8%, dichromic anhydride 2~6%.The brake pad of the present application has good friction coefficient stability, wear resistance, solves the technical bottleneck of existing carbon ceramic brake disc brake pad.

Description

Technical Field

[0001] This invention belongs to the field of automotive friction pad technology, specifically relating to an organic ceramic brake pad for carbon ceramic brake discs of road vehicles and its preparation method. Background Technology

[0002] Recently, with the increasing demands for lightweighting in electric vehicles and the continuous reduction in the production cost of carbon ceramic brake discs, carbon ceramic brake pads are poised to enter a broad market. Currently, several automakers, including BYD, Tesla, and GAC Aion, have begun to promote the commercialization of carbon ceramic brake pads.

[0003] Currently, the most widely used brake disc material is ordinary cast iron, which is prone to degradation and corrosion. Compared to cast iron discs, carbon ceramic discs are lightweight, heat-resistant, wear-resistant, and corrosion-resistant, with a stable coefficient of friction and a long service life. Although the development of carbon ceramic brake discs is becoming increasingly mature, research on matching brake pads is scarce. Existing traditional carbon ceramic brake disc organic composite brake pads mostly use a single high-temperature resistant resin as a binder. Although the temperature resistance is greatly improved, the production is difficult, and thermal degradation still occurs under extreme conditions, with a significant risk of fire. Carbon ceramic brake discs and brake pads using ceramic binders are heat- and wear-resistant, but their braking comfort is poor, making them unsuitable for road vehicles.

[0004] In summary, there is an urgent need to provide an organic ceramic brake pad that has good resistance to thermal fading, a moderate coefficient of friction, smooth braking, wear resistance, and can be matched with carbon ceramic discs. Summary of the Invention

[0005] The purpose of this invention is to provide an organic ceramic brake pad with good resistance to thermal fading, a moderate coefficient of friction, smooth braking, wear resistance, and compatibility with carbon ceramic discs.

[0006] The above objective is achieved through the following technical solution: an organic ceramic brake pad for a carbon-ceramic brake disc of a road vehicle, the raw materials of which include the following components calculated by weight percentage: 1-4% phenolic resin, 1-5% boron-modified phenolic resin, 4-15% aluminum metaphosphate, 3-7% sodium silicate, 1-3% ammonium fluoride, 1-5% magnesium oxide, 3-5% copper oxide, 2-6% aluminum powder, 1-6% carbon fiber, 1-6% aramid pulp, 8-15% steel fiber, 15-25% reduced iron powder, 6-12% copper powder, 1-3% antimony oxide, 5-8% zinc borate, 2-6% antimony trisulfide, 4-6% molybdenum disulfide, 5-8% calcined petroleum coke, 1-5% aluminum titanate, 1-4% titanium oxide, 5-12% zirconium oxide, 4-8% silicon carbide, and 2-6% chromium trioxide.

[0007] The brake material prepared using the above-mentioned component ratio is an organic ceramic composite material. The resin comprises two types: phenolic resin and boron-modified phenolic resin. These two resins have different decomposition temperatures, and their combined use promotes mutual improvement, reduces high-temperature thermal degradation, and significantly lowers production difficulty. The inorganic binder composed of aluminum metaphosphate and sodium silicate, along with its components, undergoes three stages of thermal curing: 100-200℃, 200-350℃, and 350-500℃. Titanium oxide dispersant alters the surface tension and electronegativity of the mixed fibers to prevent flocculentization. Ammonium fluoride and magnesium oxide, acting as curing agents, act on the aluminum metaphosphate, curing and setting it at 100-200℃, with subsequent continuous high-temperature curing shortening the curing time. Aluminum metaphosphate and sodium silicate, as the ceramic inorganic binder, and their components cure at high temperatures to form a continuous ceramic matrix, enhancing the high-temperature resistance and wear resistance of the brake pads. Carbon fiber and aramid fiber serve as the main high-temperature, high-modulus reinforcing matrix phases, while steel fiber is the primary reinforcing phase and also a good friction-enhancing material. Combined with reduced iron powder, it improves the thermal conductivity of the brake pads and reduces friction coefficient fade at high speeds. Copper powder acts as a good lubricant, reducing vibration during braking and minimizing wear. Silicon carbide primarily increases the high-temperature friction coefficient. Calcined petroleum coke helps reduce noise, minimize disc damage, and reduce wear. Antimony sulfide provides high-temperature lubrication, while zirconium oxide and inorganic binders form a ceramic phase and increase the friction coefficient. Zinc borate and antimony oxide are flame-retardant materials that can, to some extent, inhibit the ignition and combustion of resin decomposition products at high temperatures. Through the rational design and proportioning of these materials, a perfect match with the carbon ceramic disc is achieved, resulting in excellent braking performance.

[0008] A further technical solution is that the polymerization rates of the phenolic resin and the boron-modified phenolic resin are 30~60s and 80~90s, respectively.

[0009] A further technical solution is that the particle size of the reduced iron powder is less than 74 µm, the particle size of the zinc borate is less than 3 µm, the particle size of the antimony oxide is less than 3 µm, the particle size of the copper powder is less than 74 µm, the particle size of the calcined petroleum coke is 250~350 µm, and the particle size of the silicon carbide is less than 45 µm.

[0010] A further technical solution is that its raw materials include the following components calculated by weight percentage: 2% phenolic resin, 3% boron-modified phenolic resin, 4% aluminum metaphosphate, 5% sodium silicate, 1% ammonium fluoride, 2% magnesium oxide, 3% copper oxide, 2% aluminum powder, 5% carbon fiber, 2% aramid pulp, 8% steel fiber, 18% reduced iron powder, 6% copper powder, 3% antimony oxide, 5% zinc borate, 5% antimony trisulfide, 4% molybdenum disulfide, 5% calcined petroleum coke, 1% aluminum titanate, 1% titanium oxide, 5% zirconium oxide, 8% silicon carbide, and 2% chromium trioxide.

[0011] To achieve the above objectives, the present invention also provides a method for preparing organic ceramic brake pads for carbon ceramic brake discs of road vehicles as described above, comprising the following steps:

[0012] (1) Mixing: Weigh the raw materials by a specified weight fraction and mix for a predetermined time;

[0013] (2) Hot pressing;

[0014] (3) Heat curing: The brake pads treated in step (2) are heated from room temperature to heat curing temperature within a predetermined time, kept at the temperature for a predetermined time, and then cooled to room temperature with the heating container;

[0015] (4) Machining;

[0016] (5) Surface ablation.

[0017] A further technical solution is to first premix the fiber material, add a dispersant, and mix for 3-5 minutes. The mixing time is 3-5 minutes, the main shaft speed of the mixer is 80-120 rpm, and the flying knife speed is 2800-3200 rpm. Then, other components are mixed together for 10-15 minutes, the main shaft speed of the mixer is 80-120 rpm, and the flying knife speed is 2800-3200 rpm. Before curing, a curing agent is added and mixed.

[0018] A further technical solution is that the pressing pressure in step (2) is 450-550 kgf / cm². 2 The hot pressing temperature is 160~170 ℃, the pressure holding time is 5~15 s, the venting time is 5~10 s, the venting time is 4~6 times, and the vulcanization pressure holding time is 300~420 s.

[0019] A further technical solution is that the specific steps of step (3) are as follows: the brake pads treated in step (2) are heated from room temperature to 200°C, then heated to 350°C, kept warm for a predetermined time, then heated to 500°C again, kept warm for a predetermined time, and then cooled to room temperature with the heating container.

[0020] A further technical solution is that the machining in step (4) includes at least surface grinding.

[0021] A further technical solution is that the ablation temperature in step (5) is 550 ℃~650 ℃ and the ablation time is 3~5 min.

[0022] Compared to existing technologies, the brake pads prepared in this invention exhibit excellent resistance to thermal fading when matched with carbon ceramic discs. The AK test shows a friction coefficient above 0.35 at approximately 600℃, and the AMS test shows a minimum friction coefficient of 0.28. Furthermore, the moderate friction coefficient ensures smooth braking without vibration. It exhibits low sensitivity to speed and pressure, with minimal decrease in friction coefficient as initial braking speed and braking pressure increase. It is also wear-resistant, with wear less than 0.3mm in the AK test and a service life exceeding 100,000 kilometers. Additionally, it exhibits low noise, with no driving noise verified during testing. In summary, the organic ceramic brake pads of this invention combine the flexibility of organic materials with the high temperature resistance and strength of ceramic materials. They possess a moderate friction coefficient, relatively low production cost, moderate hardness, and the best overall friction performance, making them the most promising friction material for large-scale application when paired with carbon ceramic brake discs for road vehicles. Detailed Implementation

[0023] The present invention will now be described in detail. This description is merely illustrative and explanatory and should not be construed as limiting the scope of protection of the invention. Furthermore, those skilled in the art can combine the features in the embodiments described herein and in different embodiments based on the description in this document.

[0024] The embodiments of the present invention are as follows:

[0025] Example 1

[0026] The raw material composition of organic ceramic brake pads for carbon ceramic brake discs is as follows: 2% phenolic resin, 3% boron-modified phenolic resin, 4% aluminum metaphosphate, 5% sodium silicate, 1% ammonium fluoride, 2% magnesium oxide, 3% copper oxide, 2% aluminum powder, 5% carbon fiber, 2% aramid pulp, 8% steel fiber, 18% reduced iron powder, 6% copper powder, 3% antimony oxide, 5% zinc borate, 5% antimony trisulfide, 4% molybdenum disulfide, 5% calcined petroleum coke, 1% aluminum titanate, 1% titanium oxide, 5% zirconium oxide, 8% silicon carbide, and 2% chromium trioxide.

[0027] The manufacturing process of the organic ceramic brake pads for the carbon ceramic brake disc in this embodiment is as follows:

[0028] (1) Mixing: First, premix the fiber material, add the dispersant, and mix for 3 to 5 minutes. The main shaft speed of the mixer is 80 to 120 rpm, and the speed of the flying knife is 2800 to 3200 rpm. Then, mix the other components together for 10 to 15 minutes. The main shaft speed of the mixer is 80 to 120 rpm.

[0029] (2) Hot pressing: pressing pressure 500 kgf / cm 2 Hot pressing temperature 165℃, holding pressure for 10s, venting for 5s, venting 6 times, holding pressure for 360s;

[0030] (3) Thermoforming: The formed friction sheet is heated from room temperature to 200°C in 3 hours, then heated to 350°C in 2 hours, held for 3 hours, then heated to 500°C in 2 hours, held for 6 hours, and then cooled to room temperature in the furnace.

[0031] (4) Machining: Machining the heat-treated friction plates according to technical requirements, including surface grinding, grooving, etc.;

[0032] (5) Surface ablation: ablation temperature 600℃, ablation time 4 min.

[0033] After the brake pads in Example 1 were prepared, they were tested according to the international standard SAE J2522-2003. The main test results are shown in Table 1.

[0034] Table 1. SAE J2522-2003 test results for Example 1

[0035]

[0036] According to the test results of SAE J2522-2003, the lowest coefficient of friction in Example 1 is 0.40, the nominal coefficient of friction is 0.43, the wear of the inner sheet is 0.25 mm, and the wear of the outer sheet is 0.22 mm. The coefficient of friction is stable and the wear is low.

[0037] After the brake pads in Example 1 were prepared, AMS testing was performed, and the main test results are shown in Table 2.

[0038] Table 2 AMS test results of Example 1

[0039]

[0040] The AMS test results show that Example 1 has the lowest coefficient of friction of 0.30 and excellent thermal decay performance.

[0041] Example 2

[0042] The raw material composition of organic ceramic brake pads for carbon ceramic brake discs is as follows: 1% phenolic resin, 2% boron-modified phenolic resin, 8% aluminum metaphosphate, 7% sodium silicate, 3% ammonium fluoride, 1% magnesium oxide, 5% copper oxide, 2% aluminum powder, 1% carbon fiber, 1% aramid pulp, 10% steel fiber, 15% reduced iron powder, 8% copper powder, 1% antimony oxide, 5% zinc borate, 2% antimony trisulfide, 4% molybdenum disulfide, 5% calcined petroleum coke, 5% aluminum titanate, 2% titanium oxide, 6% zirconium oxide, 4% silicon carbide, and 2% chromium trioxide.

[0043] The preparation and testing methods are the same as in Example 1.

[0044] After the brake pads in Example 2 were prepared, they were tested according to the international standard SAE J2522-2003. The main test results are shown in Table 3.

[0045] Table 3. SAE J2522-2003 Test Results for Example 2

[0046]

[0047] According to the test results of SAE J2522-2003, Example 2 has a minimum coefficient of friction of 0.36, a nominal coefficient of friction of 0.41, an inner wear of 0.28 mm, and an outer wear of 0.23 mm. The coefficient of friction is stable and the wear is low.

[0048] After the brake pads in Example 2 were prepared, AMS testing was performed, and the main test results are shown in Table 4.

[0049] Table 4. AMS test results for Example 2

[0050]

[0051] The AMS test results show that Example 2 has the lowest coefficient of friction of 0.29, and excellent thermal decay performance.

[0052] Example 3

[0053] The raw material composition of organic ceramic brake pads for carbon ceramic brake discs is as follows: 1% phenolic resin, 1% boron-modified phenolic resin, 15% aluminum metaphosphate, 3% sodium silicate, 1% ammonium fluoride, 2% magnesium oxide, 3% copper oxide, 2% aluminum powder, 6% carbon fiber, 1% aramid pulp, 8% steel fiber, 15% reduced iron powder, 8% copper powder, 1% antimony oxide, 8% zinc borate, 2% antimony trisulfide, 4% molybdenum disulfide, 5% calcined petroleum coke, 1% aluminum titanate, 2% titanium oxide, 5% zirconium oxide, 4% silicon carbide, and 2% chromium trioxide.

[0054] The preparation and testing methods are the same as in Example 1.

[0055] After the brake pads in Example 3 were prepared, they were tested according to the international standard SAE J2522-2003. The main test results are shown in Table 5.

[0056] Table 5. SAE J2522-2003 Test Results for Example 3

[0057]

[0058] According to the test results of SAE J2522-2003, the lowest coefficient of friction in Example 3 is 0.36, the nominal coefficient of friction is 0.41, the wear of the inner sheet is 0.16 mm, and the wear of the outer sheet is 0.18 mm. The coefficient of friction is stable and the wear is low.

[0059] After the brake pads in Example 3 were prepared, AMS testing was performed, and the main test results are shown in Table 6.

[0060] Table 6. AMS test results of Example 3

[0061]

[0062] The AMS test results show that Example 3 has the lowest coefficient of friction of 0.30 and excellent thermal decay performance.

[0063] Example 4

[0064] The raw material composition of organic ceramic brake pads for carbon ceramic brake discs is as follows: 1% phenolic resin, 1% boron-modified phenolic resin, 4% aluminum metaphosphate, 3% sodium silicate, 1% ammonium fluoride, 1% magnesium oxide, 3% copper oxide, 2% aluminum powder, 1% carbon fiber, 1% aramid pulp, 15% steel fiber, 15% reduced iron powder, 6% copper powder, 1% antimony oxide, 5% zinc borate, 6% antimony trisulfide, 6% molybdenum disulfide, 8% calcined petroleum coke, 1% aluminum titanate, 4% titanium oxide, 5% zirconium oxide, 4% silicon carbide, and 6% chromium trioxide.

[0065] The preparation and testing methods are the same as in Example 1.

[0066] After the brake pads in Example 4 were prepared, they were tested according to the international standard SAE J2522-2003. The main test results are shown in Table 7.

[0067] Table 7. SAE J2522-2003 Test Results for Example 4

[0068]

[0069] According to the test results of SAE J2522-2003, Example 6 has a minimum coefficient of friction of 0.38, a nominal coefficient of friction of 0.41, an inner wear of 0.13 mm, and an outer wear of 0.17 mm. The coefficient of friction is stable and the wear is low.

[0070] After the brake pads in Example 4 were prepared, AMS testing was performed, and the main test results are shown in Table 8.

[0071] Table 8. AMS test results for Example 4

[0072]

[0073] The AMS test results show that Example 4 has the lowest coefficient of friction of 0.30 and excellent thermal decay performance.

[0074] Example 5

[0075] The raw material composition of organic ceramic brake pads for carbon ceramic brake discs is as follows: 1% phenolic resin, 1% boron-modified phenolic resin, 4% aluminum metaphosphate, 3% sodium silicate, 1% ammonium fluoride, 1% magnesium oxide, 3% copper oxide, 2% aluminum powder, 1% carbon fiber, 1% aramid pulp, 15% steel fiber, 20% reduced iron powder, 6% copper powder, 1% antimony oxide, 5% zinc borate, 3% antimony trisulfide, 5% molybdenum disulfide, 6% calcined petroleum coke, 1% aluminum titanate, 2% titanium oxide, 12% zirconium oxide, 4% silicon carbide, and 2% chromium trioxide.

[0076] The preparation and testing methods are the same as in Example 1.

[0077] After the brake pads in Example 5 were prepared, they were tested according to the international standard SAE J2522-2003. The main test results are shown in Table 9.

[0078] Table 9. SAE J2522-2003 Test Results for Example 5

[0079]

[0080] According to the test results of SAE J2522-2003, Example 5 has a minimum coefficient of friction of 0.37, a nominal coefficient of friction of 0.40, an inner wear of 0.15 mm, and an outer wear of 0.15 mm. The coefficient of friction is stable and the wear is low.

[0081] After the brake pads in Example 5 were prepared, AMS testing was performed, and the main test results are shown in Table 10.

[0082] Table 10 AMS test results of Example 5

[0083]

[0084] The AMS test results show that Example 5 has the lowest coefficient of friction of 0.31, and excellent thermal decay performance.

[0085] It should be noted that in Examples 1-5, the particle size of the reduced iron powder is less than 74 µm, the particle size of the zinc borate is less than 3 µm, the particle size of the antimony oxide is less than 3 µm, the particle size of the copper powder is less than 74 µm, the particle size of the calcined petroleum coke is 250-350 µm, and the particle size of the silicon carbide is less than 45 µm. In the examples, the polymerization rates of the phenolic resin and the boron-modified phenolic resin were controlled at 30-60 s and 80-90 s, respectively.

[0086] When selecting raw materials, the purity of magnesium oxide is ≥98%, the iron content in reduced iron powder is ≥99%, the boron oxide content in zinc borate is ≥45%, the zinc oxide content is ≥36%, the purity of antimony oxide is ≥99%, the carbon content of calcined petroleum coke is ≥99.8%, and the purity of silicon carbide is ≥97%. The supplier of the boron-modified phenolic resin is Shandong Shengquan New Material Co., Ltd., model PF6700.

[0087] For those skilled in the art, various improvements and modifications can be made without departing from the principles of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention.

Claims

1. An organic ceramic brake pad for a carbon-ceramic brake disc of a road vehicle, characterized in that, The raw materials include the following components by weight percentage: 1-4% phenolic resin, 1-5% boron-modified phenolic resin, 4-15% aluminum metaphosphate, 3-7% sodium silicate, 1-3% ammonium fluoride, 1-5% magnesium oxide, 3-5% copper oxide, 2-6% aluminum powder, 1-6% carbon fiber, 1-6% aramid pulp, 8-15% steel fiber, 15-20% reduced iron powder, 6-12% copper powder, 1-3% antimony oxide, 5-8% zinc borate, 2-6% antimony trisulfide, 4-6% molybdenum disulfide, 5-8% calcined petroleum coke, 1-5% aluminum titanate, 1-4% titanium oxide, 5-12% zirconium oxide, 4-8% silicon carbide, and 2-6% chromium trioxide; the organic ceramic brake pads for carbon ceramic brake discs of road vehicles are prepared using the following steps: (1) Mixing: First, premix the fiber material, add titanium dioxide dispersant, mix for 3-5 min, the main shaft speed of the mixer is 80-120 rpm, the speed of the flying knife is 2800-3200 rpm, then mix the other components together, mix for 10-15 min, the main shaft speed of the mixer is 80-120 rpm, the speed of the flying knife is 2800-3200 rpm, before curing, add ammonium fluoride and magnesium oxide as curing agents and mix. (2) Hot pressing; (3) Heat curing: The brake pads treated in step (2) are heated from room temperature to 200°C, then heated to 350°C and kept at that temperature for a predetermined time, then heated to 500°C and kept at that temperature for a predetermined time, and then cooled to room temperature with the heating container. (4) Machining; (5) Surface ablation.

2. The organic ceramic brake pads for carbon ceramic brake discs of road vehicles according to claim 1, characterized in that, The polymerization rates of the phenolic resin and the boron-modified phenolic resin are 30~60 s and 80~90 s, respectively.

3. The organic ceramic brake pads for carbon ceramic brake discs of road vehicles according to claim 2, characterized in that, The reduced iron powder has a particle size of less than 74 µm, the zinc borate has a particle size of less than 3 µm, the antimony oxide has a particle size of less than 3 µm, the copper powder has a particle size of less than 74 µm, the calcined petroleum coke has a particle size of 250~350 µm, and the silicon carbide has a particle size of less than 45 µm.

4. The organic ceramic brake pads for road vehicle carbon ceramic brake discs according to any one of claims 1 to 3, characterized in that, Its raw materials include the following components by weight percentage: 2% phenolic resin, 3% boron-modified phenolic resin, 4% aluminum metaphosphate, 5% sodium silicate, 1% ammonium fluoride, 2% magnesium oxide, 3% copper oxide, 2% aluminum powder, 5% carbon fiber, 2% aramid pulp, 8% steel fiber, 18% reduced iron powder, 6% copper powder, 3% antimony oxide, 5% zinc borate, 5% antimony trisulfide, 4% molybdenum disulfide, 5% calcined petroleum coke, 1% aluminum titanate, 1% titanium oxide, 5% zirconium oxide, 8% silicon carbide, and 2% chromium trioxide.

5. The method for preparing organic ceramic brake pads for carbon-ceramic brake discs of road vehicles according to any one of claims 1 to 4, characterized in that, Includes the following steps: (1) Mixing: Weigh the raw materials by a specified weight fraction and mix for a predetermined time; (2) Hot pressing; (3) Heat curing: The brake pads treated in step (2) are heated from room temperature to heat curing temperature within a predetermined time, kept at the temperature for a predetermined time, and then cooled to room temperature with the heating container; (4) Machining; (5) Surface ablation.

6. The method for preparing organic ceramic brake pads for carbon-ceramic brake discs of road vehicles according to claim 5, characterized in that, The pressing pressure in step (2) is 450–550 kgf / cm. 2 The hot pressing temperature is 160~170 ℃, the pressure holding time is 5~15 s, the venting time is 5~10 s, the venting time is 4~6 times, and the vulcanization pressure holding time is 300~420 s.

7. The method for preparing organic ceramic brake pads for carbon-ceramic brake discs of road vehicles according to claim 5, characterized in that, The machining in step (4) includes at least surface grinding.

8. The method for preparing organic ceramic brake pads for carbon-ceramic brake discs of road vehicles according to claim 5, characterized in that, In step (5), the ablation temperature is 550 ℃~650 ℃ and the ablation time is 3~5 min.

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