中国物理B ›› 2016, Vol. 25 ›› Issue (11): 116102-116102.doi: 10.1088/1674-1056/25/11/116102
• CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES • 上一篇 下一篇
Jing Zhang(张静), Zheng Chen(陈铮), Yongxin Wang(王永欣), Yanli Lu(卢艳丽)
Jing Zhang(张静), Zheng Chen(陈铮), Yongxin Wang(王永欣), Yanli Lu(卢艳丽)
摘要: Anti-structured defects bridge atom migration among heterogeneous sublattices facilitating diffusion but could also result in the collapse of ordered structure. Component distribution Ni75 AlxV25-x alloys are investigated using a microscopic phase field model to illuminate relations between anti-structured defects and composition, precipitate order, precipitate type, and phase stability. The Ni75 AlxV25-x alloys undergo single Ni3 V (stage I), dual Ni3 Al and Ni3 V (stage Ⅱ with Ni3 V prior; and stage Ⅲ with Ni3 Al prior), and single Ni3 Al (stage IV) with enhanced aluminum level. For Ni3 V phase, anti-structured defects (VNi1, NiV, except VNi2) and substitution defects (AlNi1, AlNi2, AlV) exhibit a positive correlation to aluminum in stage I, the positive trend becomes to negative correlation or smooth during stage Ⅱ. For Ni3 Al phase, anti-structured defects (AlNi, NiAl) and substitution defects (VNi, VAl) have a positive correlation to aluminum in stage Ⅱ, but NiAl goes down since stage Ⅲ and lasts to stage IV. VNi and VAl fluctuate when Ni3 Al precipitates prior, but go down drastically in stage IV. Precipitate type conversion of single Ni3 V/dual (Ni3 V+Ni3 Al) affects Ni3 V defects, while dual (Ni3 V+Ni3 Al)/single Ni3 Al has little effect on Ni3 Al defects. Precipitate order swap occurred in the dual phase region affects on Ni3 Al defects but not on Ni3 V.
中图分类号: (Point defects and defect clusters)