Conventionally, sintered materials have been considered less reliable than wrought materials in mechanical properties such as tensile strength and impact energy, because of its consequential pores. Thus, sintered materials have been thought unsuitable for applications in important safety-related parts.Now, production of improved sintered materials with tensile strength exceeding 110kgf/mm2 has been made possible by developed techniques of high density compaction, high temperature sintering, and precisely controlled heat treatment, using partially alloyed steel powders with excellent compressibility. In 1979, as the first producer in the world, Tokyo Sintered Metals Corp. pioneered production of automotive power steering oil pump parts.In every industry, compactness and light-weight are the current of the times, and applied conditions for such machine component constructural parts are getting severer. We have succeeded in developing material which has high toughness and wear-resistivity in addition to high tensile strength. This material is now applied in production of starter parts for automobile.