Quantitative determination of anti-structured defects applied to alloys of a wide chemical range

Anti-structured defects bridge atom migration among heterogeneous subFlattices facilitating diffusion but could also result in the collapse of ordered structure. Component distribution Ni₇₅Al_xV_25-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 Ni₇₅Al_xV_25-x alloys undergo single Ni₃V (stage I), dual Ni₃Al and Ni₃V (stage II with Ni₃V prior; and stage III with Ni₃Al prior), and single Ni₃Al (stage IV) with enhanced aluminum level. For Ni₃V phase, anti-structured defects (V_Ni1, Ni_V, except V_Ni2) and substitution defects (Al_Ni1, Al_Ni2, Al_V) exhibit a positive correlation to aluminum in stage I, the positive trend becomes to negative correlation or smooth during stage II. For Ni₃Al phase, anti-structured defects (Al_Ni, Ni_Al) and substitution defects (V_Ni, V_Al) have a positive correlation to aluminum in stage II, but Ni_Al goes down since stage III and lasts to stage IV. V_Ni and V_Al fluctuate when Ni₃Al precipitates prior, but go down drastically in stage IV. Precipitate type conversion of single Ni₃V/dual (Ni₃V+Ni₃Al) affects Ni₃V defects, while dual (Ni₃V+Ni₃Al)/single Ni₃Al has little effect on Ni₃Al defects. Precipitate order swap occurred in the dual phase region affects on Ni₃Al defects but not on Ni₃V.