A friction material composition that enables a friction material, which contains no copper or contains not more than 0.5 mass % of copper, to maintain sufficient friction coefficient in fade conditions at high speed such that brake temperature rises abnormally by repeated rapid braking at deceleration of 0.8 G from a vehicle speed of 200 km/h, is provided. A friction material obtained by molding the friction material composition is also provided. The friction material composition contains a binder, an organic filler, an inorganic filler, and a fibrous base material, and the friction material composition contains no copper as an element or contains not more than 0.5 mass % of copper, and also contains 2 to 5 mass % of steel fibers that have fiber lengths of 800 μm or more.

An object of the present invention is to provide a friction material that applies low load on the environment and exhibits improved friction characteristics, particularly improved fade resistance and wear resistance. The friction material of the invention contains a fibrous base material, a friction modifier, and a binder, wherein the copper content is 0.5% by mass or less in terms of elemental copper, and lithium carbonate is contained.

To provide a friction couple having an enhanced effect and stability in a low speed range, where the friction couple has a disc brake pad having a friction material manufactured from a friction material composition having a binder, a fiber base, and a friction modifier, without containing a copper component and a ferrous metallic fiber, and a stainless steel disc rotor. The present invention uses a friction material composition containing 20 - 30 weight % of a titanate relative to an entire friction material composition as an inorganic friction modifier without containing an inorganic friction modifier that has a Mohs hardness of 4 or less and is cleavable. The above-explained titanate is preferably a layer crystal structure lithium potassium titanate.

Provided is an alkali metal titanate which, when used as a constituent material of a friction material, is excellent in heat resistance and friction force and capable of effectively suppressing wear of a mating material disposed to face the friction material. The alkali metal titanate includes a sodium atom and a silicon atom. The content of the sodium atom is 2.0 to 8.5 mass %. The content of the silicon atom is 0.2 to 2.5 mass %. The ratio of the content of an alkali metal atom other than the sodium atom to the content of the sodium atom is 0 to 6.

In the friction material used for the disc brake pad, which is manufactured by forming a non-asbestos-organic (NAO) friction material composition, it is an object of this invention to provide the friction material that satisfies the laws and regulations with respect to the amount of the copper component contained therein and at the same time inhibits the generation of the just-before-stopping noise. In the friction material used for the disc brake pad, which is manufactured by forming a non-asbestos-organic (NAO) friction material composition that contains the binder, the fiber base, the inorganic friction modifier, the organic friction modifier, and the lubricant but does not contain the copper component, the friction material composition contains 0.5-5 weight %, relative to the entire amount of the friction material composition, of the fluoropolymer particle with the average particle diameter of 10-1000 μm as the lubricant and 15-35 weight %, relative to the entire amount of the friction material composition, of the zirconium oxide with the average particle diameter of 1-8 μm as the inorganic friction modifier.

Provided is a phenol resin composition for a friction material, including a component (A) of a silicone resin having a softening point of 140° C. or lower and a component (B) of a phenol resin.

A clutch assembly for a motor vehicle drivetrain includes a rigid support and a wet friction material fixed to a surface of the rigid support. The wet friction material includes a base material including a matrix of fibers and filler particles embedded in the matrix of fibers; and a binder embedded in the base material. The base material includes, by weight percent, 30-55% cellulose fibers and 10-50% calcined kaolin clay. The base material also includes at least one of 1-20% graphite having a mean particle size of 35 to 85 microns, 20-40% diatomaceous earth in combination with the binder being tung modified phenolic resin, 5-20% chopped aramid fibers, or 5-20% of novoloid fibers.

A wet friction material includes a base including a matrix of fibers and filler particles embedded in the matrix of fibers; a binder embedded in an interior of the base; and a quaternary ammonium salt containing coating on an outer surface of the base. The quaternary ammonium salt containing coating can include a quaternary ammonium salt and a solution binder.

To provide a friction pair capable of inhibiting to form a lump of a metal on a friction surface of a disc rotor, where the friction pair is consisting of a disc brake pad having a friction material manufactured from a friction material composition containing a binder, a fiber base material, and a friction modifier, but not containing a copper component and a ferrous-based metal fiber, and a stainless steel disc rotor. To use a friction material composition containing 1-6 weight % of a trimanganese tetraoxide as a friction modifier relative to an entire amount of the friction material composition but not containing any metal fiber.

A clutch assembly for a motor vehicle drivetrain includes a rigid support and a wet friction material fixed to a surface of the rigid support. The wet friction material includes a base material including a matrix of fibers and filler particles embedded in the matrix of fibers. The filler particles include calcined kaolin clay, and the base material includes, by percent weight, 5 to 60% of calcined kaolin clay. The wet friction material also includes a binder embedded in the base material. The binder is tung modified phenolic resin.