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

The invention discloses a producing method for a carbon fiber reinforced ceramic matrix automobile brake pad. The method comprises the following steps of: preparing a carbon fiber mesh tire by a needling method; performing high temperature thermal process on the prepared carbon fiber mesh tire; preparing low-intensity carbon fiber reinforced matrix carbon (C / C) composite material by adopting an isothermal chemical vapor infiltration; machining the low-intensity C / C composite material, and performing directional infiltration in a high temperature vacuum furnace to prepare C / C-SiC brake linings; and then riveting the C / C-SiC braking linings with steel back to obtain the C / C-SiC braking pad used for the automobile braking system. The method provided by the invention has the advantages that the friction coefficient of the produced automobile brake pad is high and stable; the carbon fiber reinforced ceramic matrix automobile brake pad is low in wearing and good in heat fading performance; and thus, the method is simple and feasible.

The invention aims to provide a friction material having high cleaning performance while having high friction coefficient and safety performance and a friction plate preparation method. The friction material comprises, by weight percentage, 4-10% of resin, 6-10% of coke dust, 0.5-5% of nitrile powder, 1-8% of tire powder, 1-4% of corundum, 9-20% of graphite, 1-3% of iron black, 1-3% of activated carbon, 2-5% of friction powder, 20-30% of fiber and 30-55% of packing. The method for preparing a friction plate by utilizing the materials comprises a step (1) of mixing the materials: manufacturing a friction material mixed material; a step (2) of performing prepressing: preforming the mixed material; a step (3) of performing hot pressing: placing pressed blank in a die to undergo hot pressing, and performing interval exhaust-gas disposal; a step (4) of performing heat treatment: performing constant-speed warming and thermal insulation in a graded manner from room temperature to 185 DEG C; and a step (5) of performing size processing. The friction material is applied to the field of friction materials.

The invention relates to a method for preparing a carbon fiber reinforced carbon and hexagonal boron nitride double-matrix friction material. The method comprises the following steps of: 1, spreading powder in layers: uniformly adhering boron nitride (BN) powder on two sides of each monolayer carbon fiber felt; 2, superimposing, needling and compounding: superimposing the felts obtained in the step 1 on one another, and needling the superimposed felts to obtain a BN powder-containing carbon fiber prefabricated body material; 3, chemical vapor infiltration: depositing a pyrolytic carbon matrixfrom the BN powder-containing carbon fiber prefabricated body material by adopting a chemical vapor infiltration method to obtain a carbon fiber reinforced carbon and boron nitride double-matrix (C / C-BN) friction material; and 4, graphitizing: graphitizing the C / C-BN composite material which is obtained by the step 3 to obtain the desired C / C-BN friction material. The method for preparing the carbon fiber reinforced carbon and hexagonal boron nitride double-matrix friction material has the advantages of simple and controllable production process, low preparation cost, controllable microstructure and performance of the prepared material, uniform structure, high strength, high temperature resistance, corrosion resistance, high frictional and abrasive properties and capacity of realizing industrial production.

The power-transferring metal friction sheet consists of Cu 62-72 wt%, Sn 3-5 wt%, Zn 3-5 wt%, SiO2 2-4 wt% and graphite 18-26 wt%. It is made through mixing the said components with small amount of light oil, and sintering at pressure of 16-24 kgf / sq cm. The present invention has the features of high base material strength, good cooling effect, high and stable friction coefficient, no copper transfer in the friction surface, no adhesion between the friction pair and good friction performance.

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.

A copper-based powder metallurgy friction material for a dry clutch of a heavy-duty vehicle and a preparation method thereof. The matrix components of the friction material are copper and iron, and the lubricating components are graphite particles, flake graphite, molybdenum disulfide and petroleum coke. The friction components are ferrochromium, zirconia and silicon dioxide, and the strengthening components are tin. The weight percent of the friction material composition is: copper powder 50%-60%, iron powder 1-10%, graphite particle powder 5-20%, flake graphite 1-5%, molybdenum disulfide powder 1-6%, petroleum Coke powder 1‑15%, ferrochrome powder 3‑9%, zirconia 3‑9%, silicon dioxide 1‑5%, tin powder 1‑4%. The preparation method of the friction material is as follows: preparing a mixture according to the composition of the powder metallurgy friction material, mixing the mixture evenly in a V-type mixer and pressing it into shape, and then sintering together with a copper-plated steel back to obtain a copper-based powder Metallurgical friction materials. The copper-based powder metallurgy friction material has a high and stable friction coefficient and excellent wear resistance.

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, comprising the following steps: A) making a prefabricated part; C) using polycarbosilane as the silicon source to make an impregnating solution, introducing a protective gas for pyrolysis, and repeating the impregnation-pyrolysis operation until an intermediate with a predetermined density is obtained; D) placing it in a graphite crucible For silicon particles, graphite rods are used to separate the intermediate from the silicon particles, and the silicon particles are heated to an evaporating state. Under vacuum conditions, gaseous silicon is guided to infiltrate into different sides of the intermediate, and a uniform gas-phase siliconization reaction is performed to obtain a dense density. Higher, uniform composition carbon ceramic friction material. The prepared friction material can be applied to braking parts of automobiles or rail transit systems.

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

A cast steel disc body of the high-speed train brake disc comprises, by mass, 0.2%-0.32% of carbon, 0.5%-0.7% of silicon, 0.4%-0.8% of manganese, 0.01%-0.02% of tungsten, 0.1%-0.9% of vanadium, 0.7%-0.9% of molybdenum, 1.0%-1.5% of nickel, 0.9%-1.2% of chromium, 0.01%-0.02% of titanium, 0.020%-0.035% of aluminum, 0.1%-0.3% of copper, 0.035%-0.050% of zirconium, 0.001%-0.003% of boron, 0.1%-0.2% of cobalt, the sum of the content of phosphorus and the content of sulfur is smaller than or equal to 0.01%, and the balance iron. The cast steel disc body of the high-speed train brake disc is prepared through a remelting method, vacuum melting and aluminum insertion deoxidation tapping, a Re-Ti-Si creep modifier is poured into a steel ladle through an in-ladle pouring method, and impurities are removed through an in-ladle argon blowing purification process, so that the high-speed train brake disc has enough strength and a high and stable friction coefficient, and the service life of the high-speed train brake disc is prolonged. The wear resistance is higher; and the thermal crack resistance is better.

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.