STEEL FOR COLD WORKING, METHOD FOR PRODUCING STEEL FOR COLD WORKING, METHOD FOR PRODUCING COMPONENT FOR MACHINE STRUCTURE, AND COMPONENT FOR MACHINE STRUCTURE

摘要

PROBLEM TO BE SOLVED: To provide a steel for cold working which has excellent cold workability and strength after cold working.;SOLUTION: The steel for cold working has a composition containing, by mass, 0.005 to 0.045% C, 0.005 to 0.050% Si, 0.4 to 1.0% Mn, ≤0.05% P, 0.005 to 0.050% S, 0.005 to 0.060% Al and 0.009 to 0.016% N, and the balance Fe with inevitable impurities, wherein the content of solid solution N is 0.008 to 0.015% and the structural fraction of a ferritic phase is ≥90%, and a difference between the maximum value and the minimum value in Vickers hardness (measured load of 9.8N) measured per 1 mm to a depth of 1/4 of the thickness of the steel from the surface of the steel is ≤15Hv.;COPYRIGHT: (C)2011,JPO&INPIT