Method of making grain-oriented magnetic steel sheet having low iron loss
AssigneeKawasaki Steel Corporation
InventorsYasuyuki Hayakawa, Mitsumasa Kurosawa, Michiro Komatsubara
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Abstract
Grain-oriented magnetic steel sheet made by the method comprising of hot rolling and final finish annealing, wherein (1) the O content in the steel slab is limited to up to about 30 wtppm; (2) for the entire steel sheet including an oxide film before final finish annealing, from among impurities, the Al content is limited to up to about 100 wtppm, and the contents of B, V, Nb, Se, S, and N, to up to about 50 wtppm; and (3) during final finish annealing, the N content in the steel is, at least in the temperature region of from about 850 to 950° C., limited within the range of from about 6 to 80 wtppm.
Claims3
A grain-oriented magnetic steel sheet having a low iron loss having a composition comprising from about 1.0 to 8.0 wt % Si, and an oxide film mainly comprising forsterite (Mg2SiO4), wherein the contents of Al, B, Se and S in the entire steel sheet including said oxide film are limited to up to about 50 wtppm.
Dependencies are inferred from the claim text.