| 摘要 |
PURPOSE: To reduce iron loss and to increase magnetic flux density by regulating the amount of Al in the part of specific thickness in the surface layer part to a minute amount, in a nonoriented silicon steel sheet containing specific amounts of Si, Al, C, and N. CONSTITUTION: The surface layer part of a nonoriented silicon steel sheet has a composition containing, by weight, 0.1-3.2% Si, <=0.004% Al, <=0.005% C, and <=0.005% N, and further, the thickness of the surface layer part is regulated to <=40% of the whole thickness of the steel sheet and to >=10μm per side. Moreover, the inner layer part as the balance has a composition containing 0.1-3.2% Si, 0.1-1.0% Al, <=0.005% C, and <=0.005% N. Because the Al content in the, surface layer is regulated to a practically negligible value, the nonoriented silicon steel sheet excellent in a balance between magnetic flux density and iron loss can be obtained. |
