The State Key Lab of Rolling and Automation

Song Hongyu’s postdoctoral research result was published on Acta Materialia: The role of grain colony on secondary recrystallization in grain-oriented electrical steel: New insights from an original tracking experiment

Recently, a research result entitled The role of grain colony on secondary recrystallization in grain-oriented electrical steel: New insights from an original tracking experiment by Postdoctor Song Hongyu was published on Acta Materialia (2021, 206:116611). Song Hongyu, the first author and corresponding author of this paper, Prof. Liu Haitao as the co-corresponding author.

Grain-oriented silicon steel is one of the important soft magnetic materials and is mainly used as the core material in the transformers. The sharp Goss texture is the successful application of texture control in grain-oriented silicon steel. Since Dunn first pointed out that secondary recrystallization was responsible for the formation of sharp Goss texture in 1949, the researchers have developed several theories to describe the environments for the abnormal growth of Goss grains to improve the final magnetic properties. However, the current theories still cannot completely explain the secondary recrystallization process and establish the relations between the environments for abnormal growth of Goss grains and the sharpness of final Goss texture.

Given the above problems, Song Hongyu proposed a special tracking experiment under the guidance of the Academician Wang Guodong and Prof. Liu Haitao. In this way, the effects of micro-texture characteristics in primary recrystallization matrix on secondary recrystallization were revealed and a new method to calculate the environments for the abnormal growth of Goss grains was proposed. The results showed that the γ-grain colonies facilitated the abnormal growth of low-deviation-angle Goss grains especially after the onset of secondary recrystallization and leading to sharp final Goss texture. By contrast, the abnormal growth of high-deviation-angle Goss grains may be also promoted after the initiation of secondary recrystallization in case of randomly-distributed γ-grains in primary recrystallization matrix and thus resulted in deteriorated magnetic properties. This research provided new ideas to establish the relations between the environments for the abnormal growth of Goss grains and the final magnetic properties, which may contribute to the improvement of the current secondary recrystallization theories.