Friction pair

A friction pair consisting of a stainless steel disc rotor and a disc brake pad having a friction material manufactured from a friction material composition comprising a binder, a fiber base material, and a friction modifier,

• wherein the friction material composition is entirely free of copper components so as to prevent galvanic corrosion of the stainless steel rotor and to maintain stability of a protective oxide film and is further free of metallic fibers so as to avoid localized thermal hotspots and to preserve structural strength of the friction material during repeated braking;
• and
• wherein the friction material composition contains 10-15 wt % of a carbonaceous lubricant that provides controlled lubricity, enhances wear resistance, and promotes heat dissipation and further contains 15-30 wt % of an inorganic friction modifier with a Mohs hardness of 6 or greater that produces a grinding action to stabilize the friction coefficient at low vehicle speeds, the friction material as a whole being controlled to a thermal conductivity of 1.2-3.0 W/m·K to suppress excessive temperature rise, inhibit thermal decomposition of the binder, and thereby ensure braking stability and fade resistance.

A friction pair consisting of a stainless steel disc rotor and a disc brake pad having a friction material manufactured from a friction material composition comprising a binder, a fiber base material, and a friction modifier,

• wherein the friction material composition is entirely free of copper components and metallic fibers including ferrous-base metallic fibers, so as to prevent galvanic corrosion of the stainless steel rotor and to suppress localized thermal hotspots;
• and
• wherein the friction material composition contains 10-15 wt % of a carbonaceous lubricant including a graphite sheet pulverized powder, a petroleum coke, and a resilient graphite carbon, and further contains 15-30 wt % of an inorganic friction modifier including 13-28 wt % of zirconium oxide having an average particle diameter of 0.5-8 μm, the friction material being controlled to a thermal conductivity of 1.5-2.8 W/m·K, so as to provide stable braking torque at low speeds, inhibit thermal decomposition of the binder, and ensure braking stability, wear resistance, and fade resistance.