The invention relates to a method for improving braking performance of a microporous friction material under wet conditions. A hydrophobic agent is added into the components for preparing microporous friction material. The microporous friction material is prepared from the following raw materials in percentage by weight: 10%-20% of nano-silica modified phenolic resin, 4%-14% of butadiene-styrene rubber, 5%-15% of glass fiber, 2%-11% of aramid pulp, 4%-15% of aluminum borate whisker, 4%-10% of hydrophobic agent and 3%-8% of calcium silicate, 1%-8% of artificial graphite, 2%-8% of coke, 2%-7% of mica, 5%-10% of cryolite and 4%-10% of diatomite.

A resin impregnated wet friction material that serves as the friction lining on either a clutch plate or a brake pad plate is formed as a paper matrix. The composition of the paper matrix contains graphene nanoparticles as an aid for thermal capacity and conductivity.

Method for creating a brake pad with a block of friction material, in which sodium hydroxide and sodium silicate are dissolved in water, the aqueous solution of sodium hydroxide and sodium silicate is mixed with commercial metakaolin until a wet paste is obtained, the wet paste is formed and dried until a dried geopolymeric aggregate is obtained, the aggregate is ground to a powder, the dried ground aggregate is used as an exclusive or almost-exclusive inorganic geopolymeric binder in a friction material compound and the raw compound is hot-molded under a pressure greater than a water saturation pressure at the molding temperature.

A method of making a wet friction material includes joining filler particles and fibers together and forming a base; coating an outer surface of the base with a quaternary ammonium salt containing solution; and drying the quaternary ammonium salt containing solution to form a quaternary ammonium salt containing coating on the outer surface of the base.

A present wet friction body includes a core plate, a plurality of friction parts disposed on a main surface thereof in a ring shape at intervals, a plurality of oil grooves defined by the corresponding friction parts. The friction parts include first to third friction parts in which forms of the pair of sidewalls are different each other. The first friction part includes a left sidewall inclining to the right and a right sidewall inclining to the left, with respect to an imaginary line segment, and an outer peripheral wall having a length less than a length of an inner peripheral wall. The second friction part includes a pair of sidewalls, both inclining to the right with respect to an imaginary line segment. The third friction part includes a pair of sidewalls, both inclining to the left with respect to an imaginary line segment.

A friction material presents a friction generating surface and a bonding surface facing opposite said friction generating surface. The friction material includes structural fibers, friction particles, polyvinyl alcohol fibers, and a resin. A method of forming the friction material is also disclosed. The method comprises the steps of: combining the structural fibers, the friction particles, and the polyvinyl alcohol fibers having an average diameter of less than about 11 μm, an average length of less than about 4 mm, an average denier of less than about 1, to form a substrate material; impregnating the substrate material with the resin; and curing the resin to form the friction material.

A thermosetting resin composition for a friction material includes a thermosetting resin and a lignocellulose nanofiber dispersed in the thermosetting resin. A method for producing a thermosetting resin composition for a friction material includes a first step and a second step. In the first step, a plant-based biomass containing a lignocellulose is mixed with a dispersion medium to obtain a mixture thereof, and the mixture is subjected to a defibration treatment to obtain a slurry of a lignocellulose nanofiber. In the second step, phenol is reacted with an aldehyde in the presence of an acid catalyst to obtain a thermosetting resin, and the slurry is added to the thermosetting resin. The lignocellulose nanofiber is dispersed in the thermosetting resin while removing the dispersion medium and unreacted phenol.

A number of variations may include a product including a single clutch pack having a plurality of clutch plates, and a first friction material on a first plate of the plurality of clutch plates, and a second friction material on a second plate of the plurality of plates, the first friction material being different than the second friction material, and constructed and arranged to provide a tailored combination of torque capacity and response time that would be produced by a clutch pack having solely the first friction material on plates thereof or the second friction material on plates thereof.

An improved friction material is described, comprising a binding composition based on a hydraulic binder, and its use in brake pads and industrial applications.

A method for manufacturing a friction material containing a friction modifier, a fibrous material and a binder as raw materials is provided. The method includes a step of mixing and agitating the raw materials by low frequency acoustic agitation. A content of the fibrous material in the friction material may be 1 mass % or more and 50 mass % or less. The content of the fibrous material in the friction material may be 3 mass % or more and 40 mass % or less.