| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a hot rolled steel sheet for working which has no occurrence of buckling and crease, and secures sufficient ductility by using low-cost B-added low carbon steel, and sufficiently reducing the amounts of solid solution C and solid solution N. SOLUTION: A slab having a composition containing, by mass, 0.015 to 0.08% C, 0.05 to 0.5% Mn, 0.003 to 0.5% Si, <=0.05% P, 0.005 to 0.02% S, 0.005 to 0.3% Al, <=0.006% N and B satisfying 0.8<=B/N<=2.5, and the balance Fe with inevitable impurities is reheated. After that, rolling therefor is completed at the Ar3 transformation point or higher. The steel sheet is cooled at a cooling rate of >=70 deg.C/sec in the temperature range of the Ar3 transformation point to (the Ar3 transformation point -100 deg.C), and is coiled at >500 to 630 deg.C.
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