Texture evolution of non-oriented electrical steel analyzed by EBSD and in-situ XRD during the phase transformation from γ to α

Abstract

If the phase transformation from γ to α is properly controlled in silicon steel, the cube texture is known to be produced. Two sheet samples of Fe-2 wt%Si-1 wt%Ni and Fe-3 wt%Si-2.5 wt%Ni were heated to 1100 °C, held for 2 h and then cooled. The inverse pole figure (IPF) map and the orientation distribution function (ODF) of the two samples indicate that the {100} texture is dominant in the Fe-2 wt%Si-1 wt%Ni sample whereas the {112} texture is dominant in the Fe-3 wt%Si-2.5 wt%Ni sample. In order to understand why such drastically different textures were evolved, the in-situ X-ray diffraction (XRD) analysis was made during heating and cooling of the two samples. The XRD peaks of Fe-2 wt%Si-1 wt%Ni indicate that 1100 °C is one phase region, which affects strong {100} texture by preferred orientation during cooling. However, 1100 °C is the (α + γ) two phase region for the Fe-3 wt%Si-2.5 wt%Ni. Therefore, the final texture was affected by remained orientation, which leads to strong {112} texture. This difference is attributed to the evolution of such drastically different textures between the two samples.