| 摘要 |
PURPOSE:To obtain the silicon steel plate having high strength by heating a slab or cast slab of a steel, having a composition in which respective upper limits of C, Si, Mn, S, Al, N, O, and H are limited, up to a specific temp. and subjecting the above-mentioned slab or cast slab to rollings, in succession, under respectively specified conditions at temps. not lower than and not higher than a specific temp., respectively. CONSTITUTION:A slab or cast slab of a steel having a composition consisting of, by weight, <=0.01% C, <=0.02% Si, <=0.20% Mn, <=0.010% S, <=0.040% Al, <=0.004% N, =0.005% O, <=0.0002% H, and the balance iron is prepared. This slab or cast slab is heated to 950-1150 deg.C and subjected to rolling where rolling pass of >=0.6 rolling shape ratio A represented by an equation is done at least once at >=800 deg.C, by which harmful vacancy defects are removed and deterioration in magnetic properties is prevented. Successively, rolling is done at <=800 deg.C at 35-70% reduction of area and the [100] crystal orientation is made random in a direction parallel to the rolling direction, by which magnetic properties in a medium magnetic field can be remarkably improved and high strength can be obtained. In the above equation, hi, ho, and R represent inlet plate thickness (mm), outlet plate thickness (mm), and rolling roll radius (mm), respectively. |
