THIN CAST SLAB FOR NON-ORIENTED SILICON STEEL SHEET EXCELLENT IN MAGNETIC CHARACTERISTIC, AND METHOD FOR MANUFACTURING NON-ORIENTED SILICON STEEL SHEET

摘要

PROBLEM TO BE SOLVED: To solve such problems that in the case of casting a thin cast slab with a twin-rolling method by using molten steel suitably controlling REM (rare earth metals), O and S, a non-oriented silicon steel sheet reducing a core-loss by promoting crystal grain growth in the finish-annealing time, but the crystal structure of a strip just after casting, is made to be large size because of the high cleanliness of the steel, and when the cold-rolling is applied thereafter, the stable rollability can not be obtained.;SOLUTION: The REM is added in the steel in the suitable rate to make the steel into the high purity steel and also, the cast structure is once broken by applying direct-rolling to the strip just after casting, and by progressing the recrystallization and a grain-growth with the preheat of the strip thereafter, the cast slab excellent in a cold-rollability can be obtained and then, the non-oriented silicon steel sheet excellent in magnetic characteristic can be obtained with a process with energy-saving.;COPYRIGHT: (C)2011,JPO&INPIT