HOT-ROLLED STEEL SHEET HAVING EXCELLENT COLD WORKING PROPERTIES AND HARDENING PROPERTIES, AND METHOD FOR PRODUCING SAME

摘要

Hot-rolled steel has a chemical composition containing, by mass %, C: 0.18% or more and 0.29% or less, N: 0.0050% or less, Ti: 0.002% or more and 0.05% or less, B: 0.0005% or more and 0.0050% or less, and appropriately controlled amounts of Si, Mn, P, S, Al, and a tensile strength of 500 MPa or less with a variation in tensile strength of 60 MPa or less throughout a region including the edges in the width direction of the steel sheet, and having excellent cold formability and hardenability.