40results about How to "High and stable coefficient of friction" patented technology

The invention discloses a preparation method for a carbon fiber enhanced carbon-carborundum double-matrix abrasive material. Short chopped carbon fiber, graphite powder, industrial silicon powder and caking agent are employed to be pressed into the block material of carbon fiber enhanced graphite powder and silicon powder (C/C-Si) in a cooling way; then mechanical cracking and pelleting are carried out to the prepared C/C-Si block material; next, the grains are thermally pressed into a C/C-Si biscuit; and then the C/C-Si biscuit is carbonized to prepare a C/C-Si porous body; and finally non-dipping directional fused silica impregnating is carried out to the C/C-Si porous body to prepare the carbon fiber enhanced carbon-carborundum double-matrix (C/C-SiC) abrasive material. The invention relates to a preparation method for a carbon fiber enhanced carbon-carborundum double-matrix abrasive material having higher mechanical property and excellent abrasion resistance and wear performances,with the advantages of short preparation cycle, low cost, and being capable of engineering.

The invention relates to a carbon ceramic braking pad for a high-speed train and a preparation method of the carbon ceramic braking pad. The carbon ceramic braking pad is made of carbon ceramic composite material; the carbon ceramic composite material comprises the following components in percentage by mass: 16-30 percent of carbon fibers, 20-36 percent of pyrolytic carbon, 28-46 percent of silicon carbide, 6-12 percent of molybdenum disilicide and 2-6 percent of simple substance silicon; the density of the carbon ceramic composite material is 1.8-2.4g/cm<3>; the carbon fibers are uniformly distributed in the carbon ceramic composite material in a three-dimensional network structure. According to the invention, after the high-temperature heat treatment is performed on a carbon fiber felt with the density of 0.20-0.65g/cm<3>, the pyrolytic carbon is generated in the carbon fiber felt through the thermal-gradient chemical vapor deposition carburizing treatment, then the catalytic graphitization treatment, non-immersion type melting infiltration and assembly are performed, so that the carbon ceramic braking pad for the high-speed train is obtained.The carbon ceramic braking pad is simple in preparation technology, moderate in friction coefficient, good in abrasion performance, stable in braking and strong in environmental suitability and can meet braking requirements of the high-speed train with the speed of 200Km/h.

The invention relates to a preparation method and application of a carbon/ceramic composite material, in particular to a preparation method and application of a carbon/ceramic composite material needed for braking a high-momentum delivery system. The preparation method includes: using a C/C composite material of 1.2-1.5 g/cm3 in density as a raw material; disposing the raw material in impregnation liquid I for impregnation, pyrolyzing in a protective atmosphere after impregnation, repeating impregnating-pyrolyzing operations until a carbon/ceramic composite material of 1.85-1.9 g/cm3 in density is obtained; treating the carbon/ceramic composite material obtained at high temperature until density of the carbon/ceramic composite material is lowered to 1.82-1.88 g/cm3 to obtain a pre-finished product; disposing the pre-finished product in impregnation liquid II, decomposing in a protective atmosphere after impregnation is completed, polishing after decomposing, and repeating impregnating-decomposing-polishing operations until a carbon/ceramic composite material finished product of 1.93-2.0 g/cm3 is obtained.

The invention discloses a copper-based powder metallurgy friction material for a dry clutch of a heavy-duty vehicle and a preparation method thereof. The matrix component of the friction material is copper and iron; the lubricating component is graphite particles, crystalline flake graphite, molybdenum disulfide and petroleum coke; the friction component is ferrochrome, zirconia and silicon dioxide; and the strengthening component is tin. The friction material comprises the following, by weight 50%-60% of copper powders, 1%-10% of iron powders, 5%-20% of graphite particle powders, 1%-5% of flake graphite, 1%-6% of molybdenum disulfide powders, 1%-15% of petroleum coke powders, 3%-9% of ferrochrome powders, 3%-9% of the zirconia, 1%-5% of the silicon dioxide, and 1%-4% of tin powders. The preparation method of the friction material comprises the following steps of mixing a mixture according to the composition of the powder metallurgical friction material; mixing the mixture in a V-shaped mixer evenly and pressing; and then sintering together with a copper-plated steel back to obtain the copper-based powder metallurgical friction material. The copper-based powder metallurgy frictionmaterial has high and stable friction coefficients and excellent wear resistance.

The invention relates to the technical field of brake materials, in particular to a powder metallurgy friction material for high-speed train braking and a preparation method of the powder metallurgy friction material. The powder metallurgy friction material is prepared from the following raw materials: copper powder, iron powder, copper-plated flake graphite, copper-plated graphite granules, chromium iron powder, molybdenum disulfide powder and alumina fiber through a powder metallurgy process. The powder metallurgy friction material has good mechanical properties, and is stable in friction coefficient, small in abrasion loss and good in thermal failure resistance; through the adopted raw materials and the ratio, the friction material with excellent properties can be prepared at the relatively-low sintering pressure and temperature, energy consumption is saved, a preparing process is simple and easy to control, the performance is excellent, and good application prospects are achieved.

The invention discloses a method for preparing a clutch facing through taking water soluble phenol-formaldehyde resin as an adhesion agent. The method adopts the water soluble phenol-formaldehyde resin which is multiply modified by polyvinyl alcohol, nanoscale attapulgite and micron-order copper powder as the adhesion agent, the water soluble phenol-formaldehyde resin, a friction performance conditioning agent and water are mixed to produce slurry, fibers are soaked in the slurry, are dried and are wound to form a parison, the parison is then subjected to hot-press forming to form the facing, grinding and drilling are carried out after the thermal treatment, the clutch facing is obtained. The modified adhesion agent has high solubility, cohesiveness, toughness, heat resistance, thermal fading resistance and abrasion resistance; and the clutch facing which is produced through the adhesion agent is low in cost, green and environment-friendly, can bear impact force during the processing and using processes, cannot crack and has high thermal stability, high and stable friction coefficient and low abrasion resistance.

The invention relates to a composition and a preparation method of an asbestos-free friction material taking carbon fibre or other carbon materials as a main body, and in particular to a carbon-based friction material for an automobile disc brake and a preparation method of the carbon-based friction material. The friction material and the preparation method of the friction material mainly aim at solving the technical performance problems that a brake pad is high in the heat fading of friction coefficient and wear rate and is easy in the production of brake noises, and as a formulation of the brake pad often contains asbestoid fibre, the brake pad does not meet the requirement of environment-friendliness, etc. The friction material is a novel friction material with a carbon base between a carbon-carbon base and an NAO or ceramic base. The friction material mainly comprises carbon materials such as the carbon fibre and graphite, and comprises accessories such as a resin binder and a small number of inorganic or organic fillers. The friction material is produced by hot press moulding. Compared with a friction material with an NAO or ceramic base, the carbon-based friction material for the automobile disc brake disclosed by the invention has the advantages of being reliable in brake performance, low in brake noises and long in service life, and preventing friction coupling from being damaged.

The invention aims at providing a friction material with high friction coefficient and safety performance and low noise and a preparation method of a friction plate. The friction material comprises the following components in percentage by weight: 4-10% of resin, 6-10% of coke powder, 0.5-5% of nitrile powder, 1-8% of tire powder, 1-4% of corundum, 9-20% of graphite, 1-3% of iron black, 4-5% of chromite powder, 1-3% of active carbon, 2-5% of friction powder, 20-30% of fiber and 30-55% of filler; and the preparation method of the friction plate prepared from the friction material comprises the following steps of (1) material blending, namely preparing a blended material of the friction material; (2) pre-pressing, namely pre-molding the blended material; (3) hot pressing, namely placing a pressed blank into a mould to carry out hot pressing, and then, carrying out exhaust gas disposal at intervals; (4) thermal treatment, namely heating from the room temperature to the temperature of 185 DEG C in stages at constant speed, and preserving the heat; and (5) size processing. The friction material is applied to the field of friction materials.

The invention relates to the technical field of automobiles, provides a low noise brake pad, and further provides a processing method of the low noise brake pad. The low noise brake pad comprises following raw materials of adhesive-sprayed aluminum silicate fiber, glass fiber, nitrile rubber powder, tire powder, cashew nut shell oil frictional powder, tung-oil-modified phenolic resin, red copper fiber, white zi stone powder, diatomaceous earth, apocynum fiber, iron oxide green, potassium feldspar, petroleum cokes, graphite, expanded perlite, floating beads, barium sulfate, boron nitride and soft magnetic materials. The low noise brake pad and the processing method thereof have the advantages that in the research process of a formula, after a large number of experiments, a reasonable combination of various components is achieved, and the advantages of each material are fully utilized in the materials, so that the raw materials can compensate each other for deficiencies of own performance, and better performance can be generated due to mutual cooperation. The low noise brake pad has a high and stable friction coefficient and a low wear rate during use, and at the same time, low noiseis achieved during braking.

The invention discloses a brake material for a medium-low-speed maglev train and a preparation method of the brake material. The base component of the brake material is copper, the strengthening components are zinc, aluminum and molybdenum, the lubricating components are tungsten disulfide and graphite, and the friction components are magnesium oxide and zirconium dioxide. The brake material comprises the following components in percentage by weight: 50-65% of copper, 1-6% of zinc, 1-5% of aluminum, 1-4% of molybdenum, 1-4% of tungsten disulfide, 10-18% of graphite, 6-10% of magnesium oxide and 5-12% of zirconium dioxide. The invention also discloses a preparation method of the brake material. The prepared brake material for the medium-low-speed maglev train is non-magnetic, has a high and stable friction coefficient, is good in wear resistance and high in environmental adaptability, does not damage a magnetic track, and is simple in material component, simple in process and relatively low in cost.

The invention relates to a method for manufacturing a carbon/silicon carbide brake material, in particular to a method for manufacturing a low-cost chopped carbon fiber reinforced silicon carbide brake material. The method comprises: preparing phenolic resin solution, preparing carbon fiber prepreg, cutting the prepreg, forming by warm pressing, pyrolysis carbonization, and impregnating with reaction melt. Under the premise of not preparing the interface phase, the method ensures the excellent comprehensive mechanical properties of the composite material by controlling the process and designing the microstructure of the composite material, and the process is simple, the preparation cycle is short, the repeatability is good, and the cost is low. low. The carbon/silicon carbide brake material manufactured by the invention has a high and stable friction coefficient, a small wear rate, excellent friction performance, excellent mechanical properties and oxidation resistance, and can meet the requirements of high-energy load fields such as aircraft and tanks for brake materials. .

The invention discloses a brake disc with a high friction coefficient. The brake disc is prepared from following raw materials in percentage by weight: 8 to 15% of polyacrylonitrile fibers, 10 to 20%of hybrid reinforcing fibers, 5 to 10% of zirconium silicate, 5 to 10% of magnesium oxide, 2 to 5% of antimony sulfide, 5 to 10% of graphite, 2 to 5% of molybdenum disulfide, 5 to 10% of porous iron powder, 10 to 20% of light calcium carbonate, 10 to 15% of barium sulfate, and 5 to 10 of resin. A friction material of asbestos-free low metal formula is adopted; the friction coefficient of the brakedisc is designed to be a FG grade, namely the friction coefficient is in a range of 0.40 to 0.50; the defects of a half metal formula are overcome; and the requirements of domestic automobiles and European automobiles are satisfied. The friction coefficient reaches the FG grade (0.40-0.50); the high temperature heat fade is small, the stability is high; the friction coefficient is high, the brakesensitivity is high, the safety is guaranteed, at the same time, the noise index reaches 9.1, the braking noise is reduced, the wear resistant performance is also improved, and the contradiction between the friction coefficient and wear resistant performance/comfort level is resolved.

The invention relates to the technical field of carbon-ceramic composite materials, and discloses a preparation method and application of a carbon-ceramic friction material. The preparation method comprises the following steps of: (A) preparing a prefabricated part; (B) performing deposition densification on the prefabricated part by adopting a chemical vapor deposition permeation process to prepare a carbon matrix; (C) preparing an impregnation liquid by taking polycarbosilane as a silicon source, introducing protective gas for high-temperature cracking, and repeating the impregnation and high-temperature cracking operations until an intermediate with a preset density is obtained; and (D) placing silicon particles in a graphite crucible, separating the intermediate from the silicon particles by using a graphite rod, heating the silicon particles to an evaporation state, guiding gaseous silicon to permeate into different side surfaces of the intermediate under a vacuum condition, and carrying out a uniform gas-phase siliconizing reaction to obtain the carbon-ceramic friction material with higher density and uniform composition. The prepared friction material can be applied to brake parts of automobiles or rail transit systems.

The invention belongs to the technical field of automobile parts, in particular to a treatment method for enhancing the durability of clutch friction plates. Take out, steam treatment, take out to get the pre-treated clutch friction plate; (2) microwave the pre-treated clutch friction plate for one time, immerse it in the coating solution for 8~10min, take out, second microwave dry treatment, take out, vacuum treatment The treated clutch friction plate not only has a sufficiently high and stable friction coefficient, the difference between the static friction coefficient and the dynamic friction coefficient is reduced, and the friction coefficient basically does not change with the external conditions, and has good thermal conductivity, large heat capacity and good performance. High temperature mechanical strength, and has good wear resistance and anti-adhesion, not easy to scratch the surface of the counterpart, low noise and vibration, effectively ensuring the reliability of the clutch friction plate transmission system.

The invention discloses a high-temperature-resistant ceramic brake pad and a production process thereof, and relates to the technical field of ceramic brake pad production to solve the problem that high temperature resistance of a brake pad cannot be estimated. The high-temperature-resistant ceramic brake pad comprises a steel backing; a noise reduction piece is arranged on the outer wall of the top of the steel backing, and a thermal insulating layer is bonded to the outer wall of the top of the noise reduction piece; and a friction material is arranged on the outer wall of the top of the thermal insulating layer and prepared from sepiolite fibers, asbestos fibers, potassium carbonate crystal whiskers, brass fibers, wollastonite, aramid fibers, aluminium silicate fibers, aluminium silicate, zirconite, cryolite, feldspar, vermiculite, graphite, antimony disulfide, talcum, mica, barite, porous iron powder, boron modified phenolic resin, open-loop polymerized phenolic resin and the like.The high-temperature-resistant ceramic brake pad has high impact-resistance strength, meanwhile the product density is low, the product hardness is low, braking noise is small, and braking duality isnot damaged.

The invention relates to the technical field of mechanical brake, and provides a heavy mechanical brake block. The heavy mechanical brake block comprises following raw materials including aramid pulp,floating beads, nitrile rubber powder, cashew nut shell oil friction powder, epoxy resin, red copper, white Zi stone powder, white mica powder, steel wool fibers, iron oxide green, barite, petroleumcoke, graphite, barium sulfate, heavy magnesium oxide, vanadium trioxide, chromite and tire powder. The invention further provides a machining method of the heavy mechanical brake block. The heavy mechanical brake block and the machining method have the beneficial effects that in the research process of the formula, through a large amount of experiments, multiple components are subject to reasonable matching, the full exerting of advantages of all materials in the materials can be ensured, the shortcomings of the properties of the raw materials can be compensated, the better properties can begenerated through mutual cooperation, in the use process, high and stable friction coefficients are achieved, the wear rate is low, and the brake block is not prone to rusting.

The invention relates to a preparation method of a powder metallurgy friction material, and belongs to the technical field of material processing. The invention is formed in the manner that copper andiron serve as matrix components, chromium and ferrochrome powder serve as friction components, graphite and silica serve as lubricating components, and three kinds of fiber materials are used for hybrid reinforcing; the three kinds of fiber materials have complementary advantages and can improve the high temperature resistance and abrasive resistance of the friction materials; in the sintering process, as the temperature gradually increases, glass fibers gradually become molten and are adhered to a ceramic fiber mesh and a boron fiber mesh, and the three kinds of fiber materials are mixed inthe friction material to form a three-dimensional network structure, and therefore the impact force borne by the friction material can be dispersed and reduced, the mechanical properties of the friction material can be improved, and the friction coefficient is more stable; and since the ceramic fibers have the characteristic of the small specific heat, the rising rate of the temperature of the friction material during braking is reduced, the volume change caused by rapid increase of temperature is avoided, and the stability of the friction material is further improved.