The production of low-temperature reheated grain-oriented silicon steel is mainly based on the acquired inhibitor method. Due to the additional nitriding process, a high nitrogen content exists in the oxide layer, which changes the structure of the oxide layer. In this study, the structure of the surface oxide layer after nitriding was analyzed by scanning electron microscopy (SEM), electron back-scattered diffraction (EBSD), glow discharge spectrometry (GDS), and X-ray diffraction (XRD). The size and orientation of ferritic grains in the oxide layer were characterized, and the distribution characteristics of the key elements along the thickness direction were determined. The results show that the oxide layer of the steel sample mainly comprised particles of Fe2SiO4 and spherical and lamellar SiO2, and Fe4N and fcc-Fe phases were also detected. Moreover, the size and orientation of ferritic grains in the oxide layer were different from those of coarse matrix ferritic grains beneath the oxide layer; however, some ferritic grains exhibited same orientations as those in the neighboring matrix. Higher nitrogen content was detected in the oxide layer than that in the matrix beneath the oxide layer. The form of nitrogen enrichment in the oxide layer was analyzed, and the growth mechanism of ferritic grains during the oxide layer formation is proposed.

低温再热取向硅钢的生产主要基于获得的抑制剂法。由于额外的氮化工艺，在氧化物层中存在高氮含量，这改变了氧化物层的结构。在这项研究中，通过扫描电子显微镜（SEM），电子背散射衍射（EBSD），辉光放电光谱（GDS）和X射线衍射（XRD）分析了渗氮后表面氧化物层的结构。表征了氧化层中铁素体晶粒的尺寸和取向，并确定了关键元素沿厚度方向的分布特性。结果表明，钢样品的氧化层主要由Fe2SiO4颗粒和球形和片状SiO2颗粒组成，并且还检测到Fe4N和fcc-Fe相。此外，氧化层中的铁素体晶粒的尺寸和取向与氧化层下方的粗基质铁素体晶粒的尺寸和取向不同；然而，一些铁素体晶粒表现出与相邻基体相同的取向。在氧化物层中检测到的氮含量高于在氧化物层下方的基质中的氮含量。分析了氮在氧化物层中富集的形式，提出了在氧化物层形成过程中铁素体晶粒的生长机理。在氧化物层中检测到的氮含量高于在氧化物层下方的基质中的氮含量。分析了氮在氧化物层中富集的形式，提出了在氧化物层形成过程中铁素体晶粒的生长机理。在氧化物层中检测到的氮含量高于在氧化物层下方的基质中的氮含量。分析了氮在氧化物层中富集的形式，提出了在氧化物层形成过程中铁素体晶粒的生长机理。