Surface pit forming method and member with surface pit

摘要

A forming method is provided that has surface pits, and the formed product thereof including a member adjust step for obtaining a member having a surface layer portion constructed by weak portions and high strength portion of relatively higher strength than the weak portions; and an inject step for injecting high pressure fluid to a surface of the member to remove at least a part of the weak portions for forming pits. That is, the weak portions are presented on the surface layer portion of the member on which the surface pits are to be formed. The high pressure fluid is injected to the surface layer portion to remove the weak portions from the member surface layer portion. The removed portion in the weak portions form the pits.