高硫硅钢硫化物析出行为及其微观组织和电磁性能变化#br#

为了探究高硫硅钢中的硫化物析出行为及其对钢的微观组织和电磁性能的影响，以便为工业化生产制定更为合理的硫含量控制标准，和采取更为有效措施以减轻炼钢生产的硫含量控制压力，结合0.25 %Si无取向硅钢，采用非水溶液电解提取+扫描电镜/透射电镜观察相结合的方法，研究了质量分数为0.006 8 %，0.010 2 %，0.025 5 %和0.035 3 %的硫含量条件下，钢中硫化物夹杂物的组成和存在形式，及其形貌、种类、尺寸、数量变化，以及相应的热轧、成品试样的微观组织和电磁性能变化。结果表明，随着钢中硫含量的增加，钢中的硫化物逐渐由MnS→MnS+Cu2S→Cu2S转变，数量逐渐增多，尺寸向高、低两个方向发展。相应的，导致了热轧再结晶组织的劣化和抑制了成品晶粒尺寸的长大。随着钢中硫含量的增加，钢的磁感、铁损劣化程度逐渐增大。钢中硫的质量分数平均每增加0.01 %，相应的，涡流损耗、磁滞损耗分别会劣化0.24 W/kg和0.41 W/kg，而磁感会劣化0.009 T。但是，在硫的质量分数为0.010 2 %时，铁损可以低于6.0 W/kg，而在硫的质量分数为0.025 5 %时，磁感可以高于1.75 T。据此，为设计更合理的硫含量控制标准提供了技术参考，在电磁性能满足高端用户市场需求的前提下，可以大幅度降低炼钢生产制造成本和提高炼钢生产效率。

Precipitation behavior of sulfide inclusions and changes of microstructure and electromagnetic properties in high sulfur non oriented silicon steel sheets

In order to find out the precipitation behavior of sulfide inclusions and the corresponding changes of microstructure and electromagnetic properties of high sulfur non oriented silicon steel sheets, so that to design more suitable sulfur concentration controlling limit for industrial manufacture and to release the steel making difficulty effectively, the type and composition, the size and number, and the size distribution of sulfide inclusion and the changes of finished sample microstructure and electronmagnetic properties in 0.25 % Si non oriented silicon steel sheets with different sulfur content of 0.006 8 %, 0.010 2 %, 0.025 3 % and 0.035 3 %（mass fraction） were discussed by the methods of electrolysis extraction in a non aqueous solution and SEM/TEM. The results showed that for present work, as the increase of sulfur content from 0.006 8 %  to  0.035 3 %, the types of sulfide inclusions in steel will gradually change from MnS to MnS+Cu2S, even to Cu2S, together with the number increasing, while in terms of  size, some sulfide inclusions will get larger, and some will be found more small repectively, which cause the recrystallization structure of hot rolled strips getting bad and restrain the grain growth in finished steel sheets. And it can be also found that the iron loss and magnetic induction of finished steel sheet gradually get worse as the addtion of sulfur content in steel. That is, when the sulfur content increases by 0.01 % for average, the eddy loss, hysteresis loss will increase by 0.24 W/kg  and  0.41 W/kg  respectively, and correspondingly the magnetic induction will decrease by 0.009 T . But the iron loss can still be kept less than  6.0 W/kg  when the sulfur content gets to  0.010 2 % , and the magnetic induction kept more than  1.75 T  when the sulfur content gets to  0.025 5 % .These important conclusions can help in designing more suitable sulfur content controlling limit in production, which can both decrease the manufacturing cost and increase the production efficiency of steel making, on the premise of satisfying the requirements of high grade customers.