Ab initio molecular dynamics simulations of nano-crystallization of Fe-based amorphous alloys with early transition metals

作者：Wang, Yao-Cen^*; Zhang, Yan; Kawazoe, Yoshiyuki; Shen, Jun; Cao, Chong-De

来源：Chinese Physics B, 2018, 27(11): 116401.

DOI：10.1088/1674-1056/27/11/116401

• ab initio molecular dynamics
• Fe-based amorphous alloys
• nano-crystallization
• atomic diffusion

The addition of early transition metals (ETMs) into Fe-based amorphous alloys is practically found to be effective in reducing the alpha-Fe grain size in crystallization process. In this paper, by using ab initio molecular dynamics simulations, the mechanism of the effect of two typical ETMs (Nb and W) on nano-crystallization is studied. It is found that the diffusion ability in amorphous alloy is mainly determined by the bonding energy of the atom rather than the size or weight of the atom. The alloying of B dramatically reduces the diffusion ability of the ETM atoms, which prevents the supply of Fe near the grain surface and consequently suppresses the growth of alpha-Fe grains. Moreover, the difference in grain refining effectiveness between Nb and W could be attributed to the larger bonding energy between Nb and B than that between W and B.

• 出版日期2018-11
• 单位西北工业大学; 同济大学