Friction materials can be classified into; organic materials for vehicles, sintered materials for high load/speed, and carbon materials for very high speed. Among them, sintered friction material is one of friction material that is manufactured by applying compounded metal and non-metal powder. One of the main characteristic of sintered friction material is that it shows stable friction characteristic at borad range of temperatures-from room temperatures to over 700℃ Also, it keeps excellent friction characteristic when it is wet.