Sintered member, pinion gear for starters, and production method therefor

Abstract

The present invention provides a sintered body and a production method therefor in which effects of pores remaining at a surface of the sintered body can be avoided without removing the pores by machining and plastic working, thereby obtaining strength equivalent to that of ingot materials. The sintered member comprises: a hardness distribution in which hardness contiguously varies from a surface to an inner portion; a Vickers hardness value of 730 or less at the surface; the maximum hardness of which portion exists in a region of 150 to 300 μm from the surface; wherein the maximum hardness is a Vickers hardness value of 600 or more.

Dependencies are inferred from the claim text.