On the one hand the MgO annealing separable medicine for tropistic is superior in the primary membrane organization potency silicon steel sheet production on the one hand production manner null of the tropistic uses that silicon

摘要

PROBLEM TO BE SOLVED: To form a primary film having a low film defect area rate over a coil whole length/width by dissolving a metal element of a specified quantity into in MgO to form a solid solution and conducting finish annealing to a silicon steel sheet with using a solid solution type MgO annealing separating agent having a specified CAA value and a specified particle distribution. ;SOLUTION: The grain oriented silicon steel sheet having a low iron loss is obtained by coating/drying a MgO annealing separation agent on a silicon steel sheet subjected to annealing and primary recrystallization with ≤100 ppm carbon quantity, subjecting the sheet to being wound up into a coil, annealing and secondary recrystallization and allowing it to form primary film of an inorganic mineral substance essentially comprising forsterite. The MgO annealing separation agent contains a bivalent and/or a trivalent metal element with a solid solution content rate of 0.1-1.0 mol.% based on Mg, has a CAA value of 100-600 sec. of 30°C and contains secondary grains of ≥5 μm size at a ratio of 1-50%. An annealing separation agent excellent in a primary film reaction is obtained. The bivalent metals are preferably Ca, Ba, Mn, Zn, Ni, etc., and the trivalent metals are preferably Al, Cr, Ti, Bi, etc.;COPYRIGHT: (C)1999,JPO