Produces the hot rolling steel sheet and this hot rolling steel sheet which are superior in flash weldability and upset weldability as the material the non directivity electromagnetic steel sheet

摘要

PROBLEM TO BE SOLVED: To produce a hot rolled steel plate excellent in flash weldability and upset weldability, and a nonriented silicon steel sheet produced by using the hot rolled steel plate as a stock. ;SOLUTION: This hot rolled steel plate has a composition consisting of, by weight, ≥1.0% Si, ≥0.004% Al, 0.1-0.8% Mn, ≤0.2% P, ≤0.02% S, ≤0.005% C, ≤0.005% N, and the balance essentially Fe. At this time, the number of inclusions in the steel plate is as follows: the number of inclusions of 0.1-1.0μm diameter is ≥5000pieces/mm² and that of 1.0μm diameter is ≤400pieces/mm²; or the number of inclusions of 0.1-1.0μm diameter is ≤3000pieces/mm² and that of 1.0μm diameter is ≥400pieces/mm²; or the number of inclusions o 0.1-1.0μm diameter is ≥3000pieces/mm² and that of 1.0μm diameter is ≥200 pieces/mm². The nonoriented silicon steel sheet is produced by using this steel plate as a stock.;COPYRIGHT: (C)1998,JPO