Effect Of RE On The Evolvement Of Recrystallization Microstructure And Texture Of Non-oriented Silicon Steel

Non-oriented silicon steel is the vital soft magnetic material of the electronic industry,mainly used in the manufacture of iron core of generator. At present, our country is theconsumption of the country second only to the United States. There is still a large gapbetween our country and foreign countries in terms of product quality. Many factors, suchas grain size and texture are known to influence the magnetic properties of non-orientedelectrical steel. Studies have shown that, rare earth can change the form of sulfur andmanganese in steels because of its special physical and chemical properties, which affectsthe properties of the steels. There are many kinds of rare earth elements in the mine of ourcountry which are reserved in the steels during smelting. The study is still at the primarystage that the effect of rare earth on the microstructure and properties of non-oriented siliconsteel. The microstructure evolution during recrystallization and the micro-orientation are notreported.In the laboratory, based on the steel with0.9wt%Si, non-oriented silicon steel withdifferent rare earth contents were prepared by the high frequency suspended furnace. Thehot rolling and recrystallized microstructure was observed by metallographic microscope.The effect of lanthanum on the evolvement of recrystallization microstructure of non-oriented silicon steel was studied. XRD was used to analyze the recrystallization texture, andthen the effect of lanthanum on the texture of non-oriented silicon steel was studied. ZeissSuppra55SEM was used to analyze the micro-orientation. The formation of recrystallizationmicro-orientation and the orientation relationship between matrix and new grains formedafter the recrystallization annealing was analyzed.The results showed that, in the870℃,the recrystallization started at90s and ended at120s. At the early stage of recrystallization,{110}<112> orientation made the maximumproportion among all of the recrystallized grain.However, the {110}<112> texture densityof the finished product was not strong. On the contrary,{100}<100> and {100}<110>orientation made a small proportion but the finished texture density was strong. After adding the rare earth, recrystallization nucleation occurred mainly on the matrix with {110}orientation and it became harder to form recrystallization nucleation on the matrix with {111}orientation. After adding the rare earth, the hot-rolling microstructure changed a little andthe overall density level decreased. The addition of rare earth decreased the final grain sizeof the samples without normalizing treatment. Adding0.0015wt%lanthanum improved the{100} surface texture. The grain size of normalizing treatment increased after adding rareearth and distributed unevenly. After normalizing treatment, the sample with0.0015wt%lanthanum obtained the largest recrystallized grain,37.19um. Compared with the samplewithout rare earth, the cube texture component intensity of the sample with0.0015wt%lanthanum increased. By analyzing the conclusion, people can get a better direction of thenon-oriented silicon steel with rare earth element.