Delayed process for producing excellent high-strength steel for machine structural use parts in fracture properties and mechanical structural steel parts that have been produced by this,

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing high-strength steel components for machine structural use having excellent delayed fracture characteristic and high-strength steel components for machine structural use.;SOLUTION: The method for manufacturing the high-strength steel components for machine structural use having the excellent delayed fracture characteristics has a process of molding a steel containing respective elements, by weight %, of 0.30 to 0.50 C, 0.05 to 0.30 Si, 0.20 to 0.60 Mn, 0 to 0.015 P, 0 to 0.010 S, 1.00 to 1.30 Cr and 0.40 to 1.00 Mo, and consisting of the balance Fe and inevitable impurities, to the steel components for machine structural use and a process of subjecting the molded goods to a hydrochloric acid dip treatment and regulating the corrosion weight loss rate after the hydrochloric acid dip treatment to ≥0.1wt%.;COPYRIGHT: (C)2006,JPO&NCIPI