Manufacturing method of shearing parts for hot-rolled steel sheet and shearing parts for steel plate

摘要

PROBLEM TO BE SOLVED: To stably improve fatigue characteristics of a sheared component which uses a hot-rolled steel sheet with a sheet thickness of 4-15 mm as a raw material.;SOLUTION: The hot-rolled steel sheet for a sheared component with a sheet thickness of 4-15 mm is used, which has chemical composition including, in mass%, 0.30-0.50% of C, 0.10-1.00% of Si, 0.20-1.50% of Mn, 0.020% or less of P, 0.020% or less of S, 0.50-2.00% of Cr, 0.10-1.00% of Mo, 0.10-1.00% of V, and 0.005-0.100% of T.Al, with the balance of Fe and unavoidable impurities, and which has ferrite+pearlite structure with an area ratio of bainite structure or ferrite crystal grains of 5% or less.;COPYRIGHT: (C)2013,JPO&INPIT