| 摘要 |
PROBLEM TO BE SOLVED: To provide a hot rolled steel plate excellent in sliding characteristic and die galling resistance. SOLUTION: A continuously cast slab or a slab after ingoting-slabbing, having a composition containing 0.02-0.3wt.% sol.Al and 0.005-0.03wt.% N, is cooled temporarily down to <=700 deg.C, heated to 950-1150 deg.C, and hot-roughed. Ultrahigh pressure descaling at >=25kgf/cm<2> pressure of collision is applied to at least one side of the resultant sheet bar. Then, hot finish rolling is performed, and the resultant steel plate is coiled at <=750 deg.C and pickled. By this method, the hot rolled steel plate, containing AlN precipitates by >=0.005wt.% expressed in terms of N quantity and having surface roughness of <=0.8μm Ra and <=4.0μm Rmax, can be provided.
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