PRODUCTION OF GRAIN-ORIENTED SILICON STEEL SHEET HAVING UNIFORM HIGH MAGNETIC FLUX DENSITY IN LONGITUDINAL DIRECTION OF COIL

摘要

PURPOSE:To produce a grain-oriented silicon steel sheet having a uniform and stable high magnetic flux density in the longitudinal direction of a coil by holding coarse hot rolled stock having a specified compsn. constituted of C, Si, Mn, S, Se, Al, N and Fe to a prescribed temp. and continuously executing finish rolling and cold rolling. CONSTITUTION:A cast slab contg., by weight, =0.095% C, =7.0%. Si, 0.03 to 0.16% Mn, 0.005 to 0.032% S and/or Se, 0.008 to O.052% acid soluble Al and 0.003 to 0.010% N, and the balance Fe with inevitable impurities is heated and is subjected to rough rolling, and this roughly hot rolled stock is coiled as hot-rolled. The roughly hot rolled stock is held to a temp. at which AlN is not substantially precipitated or above and is successively swept out at =1.90 deg.C, and the heel of the preceding stock is joined with the tip of the succeeding stock. Next, the coarse hot rolled stock is continuously subjected to finish hot rolling to regulate its sheet thickness into =1.7mm. At this time, the finish inlet temp. is preferably regulated to a desired temp. + or -20 deg.C over the whole length of the coil. After that, the hot rolled stock is subjected to rolling for one time or two times including process annealing.