Patent ID: 8088229

Claim:
Method for producing grain oriented magnetic steel strip using the thin slab continuous casting process, comprising the following steps: a) Melting of a steel, which beside iron and unavoidable impurities contains (in wt %) Si: 2.5-4.0%, C: 0.02-0.10%, Al: 0.01-0.065% N: 0.003-0.015%, and optionally: up to 0.30% Mn, up to 0.05% Ti, up to 0.3% P, one or more elements from the group of S, Se with contents whose total amounts to 0.04% maximum, one or more elements from the group of As, Sn, Sb, Te, Bi with contents up to 0.2% in each case, one or more elements from the group of Cu, Ni, Cr, Co, Mo with contents up to 0.5% in each case, one or more elements from the group of B, V, Nb with contents up to 0.012% in each case, b) secondary metallurgical treatment of the molten metal in a ladle furnace and in a vacuum facility, c) continuous casting of the molten metal into a strand, d) dividing of the strand into thin slabs, e) heating of the thin slabs in a furnace standing inline to a temperature ranging between 1050 and 1300° C., the dwell time in the furnace being 60 minutes maximum, f) continuous hot rolling of the thin slabs in a multi-stand hot rolling mill standing inline into hot strip having a thickness of 0.5-4.0 mm, during this hot rolling stage the first forming run being carried out at a temperature of 900-1200° C. with a deformation strain of more than 40%, at least two subsequent hot rolling passes being rolled with the two phases (α-γ) being present in the mixed state, the reduction per pass in the final hot rolling run being 30% maximum, g) cooling of the hot strip, h) reeling of the hot strip into a coil, i) cold rolling of the hot strip into cold strip having a final thickness of 0.15-0.50 mm, j) recrystallization and decarburization annealing of the cold strip, k) application of an annealing separator onto the strip surface, and l) final annealing of the recrystallization and decarburization annealed cold strip in order to form a Goss texture.