MANUFACTURE METHOD OF HIGH-EFFICIENCY NON-ORIENTED SILICON STEEL WITH EXCELLENT MAGNETIC PERFORMANCE

摘要

A manufacture method of high-efficiency non-oriented silicon steel with excellent magnetic property, which comprises the following steps: 1) smelting and casting; chemical compositions of non-oriented silicon steel, by weight percent, are: C≦0.0040%, Si: 0.1˜0.8%, Al: 0.002˜1.0%, Mn: 0.10˜1.50%, P: ≦0.2%, Sb: 0.04˜0.08%, S≦0.0030%, N≦0.0020%, Ti≦0.0020%, and the rest is Fe and unavoidable inclusions; molten steel in accordance with the above compositions is smelted and then casted into billets; 2) hot-rolling and pickling; heating temperature for slab is 1100° C.˜1150° C. and finish-rolling temperature is 860° C.˜920° C.; after rolling, the hot-rolled product is air cooled, during which air cooling time t: (2+30×Sb %)s≦t≦7 s; thereafter reeling at a temperature ≧720° C. ; 3) cold-rolling; rolling to form cold-rolled plate with target thickness at a reduction ratio of 70˜18%; 4) annealing; heating up the cold-rolled plate to 800˜1000° C. at heating rate of ≧15° C./s, and holding time is 10 s˜25 s. Under the precondition to ensure magnetic properties, this invention implements low cost manufacture of high efficiency electric steel by adding elements advantageous to favorable texture during steel making, controlling contents of adverse elements and coordinating air cooling time control during hot-rolling with high temperature reeling.