Friction and Wear Properties of Integrated Composite Copper-Based Friction Materials

A new sintered composite friction material consisting of mechanically-alloyed copper-based composite powders has been developed. It has a unique microstructure of fine hard particles that are embedded in the matrix of the copper-based primary particles. This friction material reduces abrasive wear and/or seizures that are often caused by hard particles which become detached from the matrix, because the hard particles in this material are bonded tightly to the matrix even under harsh service conditions. The fine hard particles are also very useful for improving high friction force when contacting a surface material. Therefore, this new friction material provides a higher friction coefficient than the conventional material containing coarse hard particles. Furthermore, this friction material is less abrasive to the surface material than the conventional one. The new sintered composite friction material shows outstanding performance and reliability when used as a friction component in some friction devices, such as magnetic clutches in automotive air-conditioners and brake systems. The friction characteristics are bound to be superior to those of the conventional sintered copper alloy or organic material currently used for such friction components.