表面机械研磨/异步轧制无取向硅钢薄带的渗硅行为

Siliconizing behavior in non-grain oriented silicon steel after surface mechanical attrition treatment and cross shear rolling

对w(Si)=3%无取向硅钢进行表面机械研磨处理(SMAT)和异步轧制(CSR),获得表面纳米结构,再进行550～650℃、4 h固体粉末渗硅处理,用透射电镜(TEM)、扫描电镜(SEM)和X射线衍射仪(XRD)研究表层组织演变。结果表明:经过SMAT后,w(Si)=3%无取向硅钢表面形成了等轴状、取向呈随机分布的、晶粒尺寸为10 nm的纳米晶组织;异步轧制后,表面纳米晶组织保持不变;550～650℃、4 h渗硅处理后,SMAT+CSR样品表面形成化合物层,其厚度随着温度的升高由17μm增加到52μm;化合物层由Fe3Si和FeSi相组成.

Nanostructured surface layer was fabricated on a 3%（mass fraction） non-grain oriented silicon steel by means of surface mechanical attrition treatment（SMAT） and cross-shear rolling（CSR）,and then a solid powder siliconizing treatment was carried out for the SMAT＋CSR sample at 550~650 ℃ for 4 h.The microstructural evolution was examined by using transmission electron microscopy（TEM）,scanning electron microscopy（SEM） and X-ray diffraction（XRD）.Experimental results show that： equiaxed nanocrystallines with random orientations and about 10 nm in size were produced after the SMAT,which remain unchanged after the CSR.After the siliconizing treatment at 550~650 ℃ for 4 h,a compound layer forms on the SMAT＋CSR sample,the layer thickness increases from 17 to 52 μm with the increment of the siliconizing temperature.The compound layer consists of Fe3Si and FeSi phases.