| 摘要 |
PURPOSE: A method is provided to manufacture an oriented silicon steel having superior magnetic properties through the low temperature slab reheating method without carrying out the nitriding process by properly controlling conditions of second recrystallization annealing of high temperature annealing so as to reinforce inhibitors, thereby effectively restraining first recrystallized grains. CONSTITUTION: In a method for manufacturing an oriented silicon steel comprising the processes of hot rolling the reheated silicon steel slab by reheating a silicon steel slab comprising 0.01 to 0.1 wt.% of C, 1.0 to 4.8 wt.% of Si, 0.015 to 0.05 wt.% Al, 0.05 to 0.2 wt.% of Mn, 110 ppm or less of N, 0.01 wt.% or less of S and a balance of Fe and other inevitable impurities to a temperature of 1000 to 1250 deg.C; precipitation annealing the hot rolled plate, pickling and cold rolling the steel plate; coating an annealing separator on the decarburization annealed steel plate after decarburization annealing the cold rolled steel plate; and high temperature annealing the annealing separator coated steel plate, the high temperature annealing further comprises the steps of maintaining the annealing separator coated decarburized cold rolled steel plate under mixed dry gas atmosphere (N2 and H2) at a temperature of 700 to 900 deg.C for 1 to 20 hours; elevating temperature to 1150-1250 deg.C under mixed dry gas atmosphere (N2 and H2); and maintaining the steel plate under pure hydrogen dry gas atmosphere at the same temperature for 1 to 20 hours.
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