First‐Principles Study on the Effect of Trace Elements on the Diffusion of C Atoms in Fe‐Si Alloy

Abstract Decarburization is very important to the quality of Fe−Si alloy products. The higher the decarburization efficiency, the lower the carbon content, and the better the magnetic properties of Fe−Si alloy products during use. In this paper, the effects of trace elements (Al, Cr, Cu, Mn, Ni, P, S, Si) in Fe−Si alloy on the diffusion of C atoms are studied by first‐principles, and the diffusion energy barrier, diffusion activation energy and diffusion coefficient of C atoms are calculated. The results show that the trace elements Mn and P in Fe−Si alloy can promote the diffusion of C atoms. By adjusting the content of Mn and P, the decarburization efficiency of Fe−Si alloy can be improved and the decarburization process can be optimized. Temperature and diffusion activation energy affect the diffusion coefficient of C atoms. The increase of temperature and the decrease of diffusion activation energy leads to the increase of diffusion coefficient of C atoms, and finally improve the decarburization efficiency. The research conclusions of this paper can be used to improve the decarburization process of Fe−Si alloy, improve the decarburization efficiency, improve the quality of Fe−Si alloy products.