High-strength mechanical components and its fatigue properties improved method excellent in fatigue characteristics

摘要

PROBLEM TO BE SOLVED: To provide high strength machine parts having a notched part with the radius of curvature of ≤25 mm and further having a surface HV hardness of ≥250, and to provide a method for improving its fatigue strength.;SOLUTION: Regarding the high strength machine parts having excellent fatigue strength, in machine parts having a composition of, by mass, 0.1 to 1.2% C, and the balance Fe with inevitable impurities, and having a notched part with the radius of curvature of ≤25 mm, the HV hardness of the surface is ≥250, and further, the compressive residual stress of the surface layer in the notched part is -100 to -1,500 MPa, and to provide a method for improving its fatigue strength.;COPYRIGHT: (C)2006,JPO&NCIPI