Production method of the crystal grain orientation electric steel sheet of the high flux density which is based on low temperature throb heating law

摘要

(57) Abstract Production method of the crystal grain orientation electric steel sheet of high flux density in order to use as the iron core of trance and the like is disclosed. With this method, cold after being rolled, the inhibiter which holds down the growth of the primary recrystallization particle is formed to last thickness, it is possible to do low temperature throb heating, with that. The method is done like below. Silicon steel throb is heated, the heat after rolling, that hot-rolled sheet steel annealing is done. Cold rolling the steel sheet which annealing is done at one stage, it forms the cold rolled steel, decarbonizes that cold rolled steel. The annealing separator is expanded to that decarbonization steel sheet, last hot annealing is done. As for the silicon steel throb, weight % with C of the 0.02-0.045%, Si of the 2.90-3.30%, Mn of the 0.05-0.30%, Al of the 0.005-0.019%, N of the 0.003-0.008% and S of 0.006% or less (description above the main component is), in addition to the remaining of the impurity where Cu of the 0.30-0.70%, Ni of the 0.03-0.07%, Cr, or Fe and other things of the 0.03-0.07% are not avoided in addition to the remaining of the impurity where B, or Fe and other things of the 0.001-0.012% are not avoided or above-mentioned main component, or above-mentioned main component, as for B of the 0.001-0.012%, Cu of the 0.30-0.70%, Ni of the 0.03-0.07%, Cr, and remainder of the 0.03-0.07% the impurity where Fe and other things are not avoided is included. The throb heating temperature for steel throb is the 1050-1250C. From 30 seconds under nitrogen content atmosphere which possesses the dew point of the 30-70C 10 minutes, decarbonizing and nitriding going simultaneously at temperature of the 850-950C, it does decarbonization process.