Process for producing grain-oriented silicon steel strip

Claim 1

A process for producing a grain-oriented silicon steel strip having [110] <001> orientation, consisting essentially of the steps of: continuously casting a silicon steel slab; heating said continuously cast silicon steel slab at a temperature of 1300° C. or higher, which slab contains from 2.0 to 4.0% by weight of silicon and not more than 0.085% by weight of carbon as basic components; hot rolling said heated continuously cast silicon steel slab at a finishing temperature of from 950° to 1200° C., thereby obtaining a hot rolled strip; subjecting the hot rolled strip to at least one cold rolling step; subjecting the thus cold rolled strip to a decarburization annealing step; and, subjecting the thus annealed sheet to a final high temperature annealing, wherein, during said hot rolling, the steel slab is subjected to at least one hot rolling pass at a temperature range of from 950° C. to 1250° C., said hot rolling being carried out with upper and lower rolls having circumferential speeds different from each other and which pass is sufficient to generate a plastic flow which is asymmetric in the upper and lower regions of the steel slab, as seen in the cross section of the steel slab in the rolling direction, and due to said assymmetric plastic flow, the grain-oriented silicon steel strip being free from streaks.