Search

CN-121991458-A - Brake pad friction material, preparation method thereof, brake pad and application

CN121991458ACN 121991458 ACN121991458 ACN 121991458ACN-121991458-A

Abstract

The invention belongs to the technical field of brake pad friction materials, and particularly relates to a brake pad friction material, a preparation method thereof, a brake pad and application thereof. The friction material for the brake pad comprises, by weight, 100 parts of phenolic resin, 80-120 parts of silicon carbide, 5-15 parts of brass fibers, 0.5-3 parts of graphene oxide, 1-5 parts of nano zirconium silicate modified single-wall carbon nanotubes, 30-60 parts of barite powder, 10-30 parts of calcined kaolin and 0.5-1.5 parts of auxiliary agents. According to the brake pad friction material provided by the invention, the preparation raw materials are coordinated, so that the hardness, wear resistance and heat conductivity of the friction material are improved.

Inventors

  • ZHANG XIAOHAO
  • FANG ZHIFENG
  • CHEN PAI

Assignees

  • 湖南金力高新科技股份有限公司

Dates

Publication Date
20260508
Application Date
20260205

Claims (10)

  1. 1. The friction material for the brake pad is characterized by comprising the following preparation raw materials in parts by weight: 100 parts of phenolic resin, 80-120 parts of silicon carbide, 5-15 parts of brass fiber, 0.5-3 parts of graphene oxide, 1-5 parts of nano zirconium silicate modified single-wall carbon nano tube, 30-60 parts of barite powder, 10-30 parts of calcined kaolin and 0.5-1.5 parts of auxiliary agent.
  2. 2. The brake pad friction material of claim 1, wherein at least one of the following (1) - (4) characteristics is satisfied: (1) The grain diameter D50 of the silicon carbide is 5-30 mu m; (2) The aspect ratio of the brass fiber is more than 20; (3) The length-diameter ratio of the brass fiber is 25-35; (4) The average diameter of the brass fiber is 10-50 mu m.
  3. 3. The brake pad friction material according to claim 1 or 2, wherein the nano zirconium silicate modified single-walled carbon nanotubes are prepared from single-walled carbon nanotubes, zirconium salt and a silicon source.
  4. 4. A brake pad friction material according to claim 3, wherein at least one of the following (1) to (6) is satisfied: (1) The mass molar ratio of the single-walled carbon nanotube to the zirconium salt to the silicon source is 1g:0.01 mol-0.05 mol:0.01 mol-0.05 mol; (2) The zirconium salt is zirconium oxychloride; (3) The silicon source is ethyl orthosilicate; (4) The grain diameter D50 of the barite powder is 1-10 mu m; (5) The particle size D50 of the calcined kaolin is 1-5 mu m; (6) The auxiliary agent comprises at least one of KH-550 and KH-560.
  5. 5. A method for preparing a brake pad friction material according to any one of claims 1 to 4, comprising the steps of: mixing the nano slurry, the modified filler mixture, the phenolic resin and the brass fibers to obtain brake pad friction material slurry; Wherein the nano slurry comprises graphene oxide and nano zirconium silicate modified single-walled carbon nanotubes; the modified filler mixture comprises silicon carbide, barite powder and calcined kaolin.
  6. 6. The method for preparing a brake pad friction material according to claim 5, wherein the preparation of the nano zirconium silicate modified single-walled carbon nanotube comprises the following steps: Carboxylating the single-walled carbon nanotube to obtain carboxylated single-walled carbon nanotube; The carboxylated single-walled carbon nanotubes, zirconium salt, a silicon source, a catalyst, a dispersing agent and a mixed solvent are mixed to obtain mixed sol; The pH value of the mixed sol is regulated to be more than 9 by ammonia water, and after aging, the mixed sol is subjected to post-treatment and calcination treatment.
  7. 7. The method for producing a brake pad friction material according to claim 6, wherein at least one of the following characteristics (1) to (11) is satisfied: (1) The carboxylation treatment comprises the following steps: Mixing single-wall carbon nanotubes and mixed acid, and refluxing at constant temperature; Wherein the mixed acid is a mixture of concentrated nitric acid and concentrated sulfuric acid; (2) The catalyst is hydrochloric acid, and the molar concentration of the hydrochloric acid is 0.1 mol/L-0.15 mol/L; (3) The dispersing agent is polyvinylpyrrolidone; (4) The mixed solvent is ethanol water solution; (5) The single-walled carbon nanotube, catalyst mass volume of dispersant and mixed solvent the ratio is 1g to 1ml to 1.5ml, 0.1g to 0.15g to 100ml to 110ml; (6) The carboxylated single-walled carbon nanotube, zirconium salt, silicon source, catalyst, dispersant and mixed solvent are mixed, and the method comprises the following steps: Mixing zirconium salt, a silicon source and a mixed solvent according to a preset proportion under stirring, and adding a catalyst and a dispersing agent to obtain precursor sol; ultrasonically dispersing carboxylated single-walled carbon nanotubes in a precursor sol; (7) The post-treatment comprises the following steps: Obtaining an aged solid product, washing the solid product with ethanol to be neutral, and drying the solid product to constant weight; (8) The calcination treatment comprises the following steps: calcining a dried product obtained by post-treatment at 500-700 ℃ in inert atmosphere; (9) The preparation of the nano slurry comprises the following steps: Ultrasonically dispersing graphene oxide and nano zirconium silicate modified single-walled carbon nanotube probes in ethanol to obtain nano slurry; (10) The preparation of the modified filler mixture comprises the following steps: After separately drying silicon carbide, barite powder and calcined kaolin, mixing with an ethanol solution of a silane coupling agent, aging and drying to obtain the modified filler mixture; (11) The mixing process comprises the following steps: Mixing phenolic resin and nano slurry at 50-60 ℃, mixing with the modified filler mixture, and then mixing with brass fibers.
  8. 8. A brake pad comprising a friction material coating made of the friction material according to any one of claims 1 to 4.
  9. 9. The brake pad of claim 8, wherein at least one of the following (1) - (3) characteristics is satisfied: (1) The thickness of the coating is 8 mm-12 mm; (2) The surface of the brake pad comprises a multi-directional drainage groove in a shape of a Chinese character 'mi'; (3) And a metal plug-in unit with the same height as the coating is assembled beside the steel back at the screwing side of the brake block.
  10. 10. Use of a brake pad according to claim 8 or 9 in the field of brake systems.

Description

Brake pad friction material, preparation method thereof, brake pad and application Technical Field The invention belongs to the technical field of brake pad friction materials, and particularly relates to a brake pad friction material, a preparation method thereof, a brake pad and application thereof. Background The carbon ceramic disc (C/C-SiC) is a core component of a high-end braking system, has the advantages of high heat resistance (working temperature is less than or equal to 1200 ℃), low wear rate (less than or equal to 0.01 mu m/time), light weight (density is 2.0g/cm 3~2.2g/cm3) and the like, but has the inherent defects of high surface microcosmic flatness (Ra is less than or equal to 0.2 mu m), contains 5% -15% of free silicon, and easily forms a compact water film on a friction interface after the free silicon absorbs moisture, so that a water lubrication effect is caused, and the friction coefficient is suddenly reduced from a dry state of 0.35-0.45 to a wet state of 0.20-0.25. The existing method for solving the problems adopts a linear groove hydrophobic brake pad, a drainage channel is provided through a linear groove, the retention time of a water film is reduced, a hydrophobic agent is added to reduce the water absorption rate of a friction material, the wet friction coefficient obtained through the test of the method is 0.23-0.25, the brake response delay is 1.6 s-1.8 s, the brake friction coefficient fluctuation is 0.09-0.11 for 5 times continuously, and the brake distance (60 km/h-0) is prolonged by 28% compared with the dry friction coefficient. However, the use of parallel linear grooves has at least the following disadvantages: (1) The water can drain in a single direction only, the space between grooves is 40mm too large, the water film can drain after flowing for a long distance, the depth of the grooves is only 0.3mm, the water containing amount is limited, the residence time of the water film at a friction interface during braking is more than or equal to 0.8s, the water film can not drain in time, friction contact is continuously hindered, a compact water film formed by free silicon moisture absorption is parallel to a linear groove, the drainage efficiency is further reduced, and the friction coefficient is lower than 0.25 for a long time. (2) The novel carbon ceramic disc brake has the advantages that no special water film breaking structure is adopted, the water film is extruded only by depending on the self hardness of the friction material, the surface of the carbon ceramic disc is smooth, the initial contact pressure is dispersed, the water film is difficult to puncture rapidly, the effective contact area is less than or equal to 30% in the initial braking period of 0.5-1.0 s, the braking moment is insufficient, the response delay is more than or equal to 1.6s, and before the water film is broken, the friction material and the carbon ceramic disc slide, so that braking shake is caused, and the friction coefficient fluctuation is more than or equal to 0.09. (3) The linear groove design causes uneven stress on the friction surface, the groove area is free of friction materials, the effective friction area is reduced by 15%, the water absorption rate of the material can be reduced only by the water repellent, the formed water film can not be actively broken, the friction coefficient is severely fluctuated between 0.23 and 0.32 when the continuous wet state braking is carried out, and the braking distance deviation is more than or equal to 3m, so that the driving safety is influenced. Disclosure of Invention In order to solve the problems, the invention provides a brake pad friction material, a preparation method thereof, a brake pad and application. To solve at least one aspect of the above technical problems. The invention is realized by the following technical scheme: in a first aspect, the invention provides a brake pad friction material, which comprises the following preparation raw materials in parts by weight: 100 parts of phenolic resin, 80-120 parts of silicon carbide, 5-15 parts of brass fiber, 0.5-3 parts of graphene oxide, 1-5 parts of nano zirconium silicate modified single-wall carbon nano tube, 30-60 parts of barite powder, 10-30 parts of calcined kaolin and 0.5-1.5 parts of auxiliary agent. In a second aspect, the present invention provides a method for preparing the brake pad friction material, including the following steps: mixing the nano slurry, the modified filler mixture, the phenolic resin and the brass fibers to obtain brake pad friction material slurry; Wherein the nano slurry comprises graphene oxide and nano zirconium silicate modified single-walled carbon nanotubes; the modified filler mixture comprises silicon carbide, barite powder and calcined kaolin. In a third aspect, the present invention provides a brake pad comprising a friction material coating made of the friction material described above. In a fourth aspect, the present invention provides