中国物理B ›› 2018, Vol. 27 ›› Issue (11): 116401-116401.doi: 10.1088/1674-1056/27/11/116401
所属专题: SPECIAL TOPIC — 80th Anniversary of Northwestern Polytechnical University (NPU)
• SPECIAL TOPIC—Recent advances in thermoelectric materials and devices • 上一篇 下一篇
Yao-Cen Wang(汪姚岑), Yan Zhang(张岩), Yoshiyuki Kawazoe, Jun Shen(沈军), Chong-De Cao(曹崇德)
Yao-Cen Wang(汪姚岑)1,2, Yan Zhang(张岩)3, Yoshiyuki Kawazoe4, Jun Shen(沈军)5, Chong-De Cao(曹崇德)1,2
摘要:
The addition of early transition metals (ETMs) into Fe-based amorphous alloys is practically found to be effective in reducing the α-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 α-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.
中图分类号: (Studies/theory of phase transitions of specific substances)