摘要 |
Provided is a manufacturing method for machine parts having a surface hardness of at least 58 HRC, in which a superior stable rolling-contact fatigue life is achieved even if there is no reduction in nonmetallic inclusions or decrease in size thereof when the steel is manufactured, compared to steel material for which there is a reduction in nonmetallic inclusions and a decrease in size thereof when the steel is manufactured. In addition to a process for imparting to steel for mechanical structures the steel shape or a process for imparting the subsequent machine part shape, the method includes a process in which the steel is worked in the previous process, the steel is heated to at least 780°C, and a hydrostatic pressure of at least 80 MPa is applied to create very close contact at the interface between the nonmetallic inclusions in the steel and the steel, which is the parent phase, after which some or all of the steel is quenched and tempered. |