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Anti-structured defects bridge atom migration among heterogeneous sublattices facilitating diffusion but could also result in the collapse of ordered structure.Component distribution Ni_(75)Al_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 Ni_(75)Al_xV_(25-x) alloys undergo single Ni_3V(stage Ⅰ),dual Ni_3Al and Ni_3V(stage Ⅱ with Ni_3V prior;and stage Ⅲ with Ni_3Al prior),and single Ni_3Al(stage Ⅳ) with enhanced aluminum level.For Ni_3V phase,anti-structured defects(V_(Ni1),Niy,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 Ni_3 Al 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 Ni_3Al precipitates prior,but go down drastically in stageⅣ.Precipitate type conversion of single Ni_3V/dual(Ni_3V+Ni_3Al) affects Ni_3V defects,while dual(Ni_3V+Ni_3Al)/single Ni_3 Al has little effect on Ni_3Al defects.Precipitate order swap occurred in the dual phase region affects on Ni_3Al defects but not on Ni_3V.
Anti-structured defects of atom migration among heterogeneous sublattices facilitating diffusion but could also result in the collapse of ordered structures. Component distribution Ni_ (75) Al_xV_ (25-x) alloys are investigated using a microscopic phase field model to illuminate relations between anti- (75) Al_xV_ (25-x) alloys undergo single Ni_3V (stage Ⅰ), dual Ni_3Al and Ni_3V (stage Ⅱ with Ni_3V prior; and stage Ⅲ with Ni_3Al prior), and single Ni_3Al (stage Ⅳ) with enhanced aluminum level.For Ni_3V phase, anti-structured defects (V_ (Ni1), Niy, except V_ (Ni2)) and substitution defects ), Al_v) exhibit a positive correlation to aluminum in stage I, the positive trend becomes to negative correlation or smooth during stage Ⅱ. For Ni_3 Al 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 from stage Ⅲ and lasts to stage Ⅳ.V_ (Ni) and V_ (Al) fluctuate when Ni_3Al precipitates prior, but go down drastically in stageⅣ.Precipitate type conversion of single Ni_3V / dual (Ni_3V + Ni_3Al) affects Ni_3V defects, while dual (Ni_3V + Ni_3Al) / single Ni_3 Al has little effect on Ni_3Al defects. Precipitate order swap occurred in the dual phase region affects on Ni_3Al defects but not on Ni_3V.