| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a high strength hot rolled steel sheet which has excellent removability of Si scale, and has excellent surface properties. SOLUTION: A slab having a steel composition containing, by mass, 0.03 to 0.25% C, 0.1 to 2.5% Si and 0.05 to 2.0% Mn, or further containing one or more kinds selected from 0.05 to 2.0% Cr, 0.30 to 1.5% Cu, 0.30 to 1.5% Ni, 0.02 to 0.30% Nb and 0.02 to 0. 30% Ti, and the balance Fe with inevitable impurities is heated and held at a surface temperature in the range of 1,200 to 1,280 deg.C for >=75 min. The slab surface temperature before final descaling directly before finish rolling is controlled to <=1,180 deg.C, and the slab is subjected to final descaling, is finish-rolled, and is thereafter coiled.
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