HOT ROLLED STEEL SHEET HAVING HIGH RESISTANCES AGAINST SECONDARY-WORK EMBRITTLEMENT AND BRAZING EMBRITTLEMENT AND ADAPTED FOR ULTRA-DEEPDRAWING AND A METHOD FOR PRODUCING THE SAME

摘要

HOT ROLLED STEEL SHEET HAVING HIGH RESISTANCES AGAINST SECONDARY-WORK EMBRITTLEMENT AND BRAZING EMBRITTLEMENT AND ADAPTED FOR ULTRA-DEEP DRAWING AND A METHOD FOR PRODUCING THE SAME A hot rolled steel sheet having a specifically limited composition and having a specifically limited small particle size of ferrite constituting the steel sheet has high resistances against secondary-work embrittlement and brazing embrittlement and is adapted for ultra-deep drawing. The specifically limited small particle size of the ferrite can be obtained by limiting specifically the hot rolling condition of a slab having the specifically limited composition.