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

作　　者：张静 陈铮 王永欣 卢艳丽 

机构地区：[1]School of Materials Science and Engineering, Northwestern Polytechnical University

出　　处：《Chinese Physics B》2016年第11期393-398,共6页中国物理B（英文版）

基　　金：Project supported by the Natural Science Basic Research Plan in Shaanxi Province of China(Grant No.2016JQ5014);the Fundamental Research Funds for the Central Universities,China(Grant No.3102014JCQ01024);the Research Fund of the State Key Laboratory of Solidification Processing(NWPU),China(Grant No.114-QP-2014);the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20136102120021);the National Natural Science Foundation of China(Grant Nos.51474716 and 51475378)

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 Ni（75）AlxV（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）AlxV（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）,Niy,except V（Ni2）） and substitution defects（Al（Ni1）,Al（Ni2）,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（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 stageⅣ.Precipitate type conversion of single Ni3V/dual（Ni3V＋Ni3Al） affects Ni3V defects,while dual（Ni3V＋Ni3Al）/single Ni3 Al has little effect on Ni3Al defects.Precipitate order swap occurred in the dual phase region affects on Ni3Al defects but not on Ni3V.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）AlxV（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）AlxV（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）,Niy,except V（Ni2）） and substitution defects（Al（Ni1）,Al（Ni2）,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（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 stageⅣ.Precipitate type conversion of single Ni3V/dual（Ni3V＋Ni3Al） affects Ni3V defects,while dual（Ni3V＋Ni3Al）/single Ni3 Al has little effect on Ni3Al defects.Precipitate order swap occurred in the dual phase region affects on Ni3Al defects but not on Ni3V.

关 键 词：defects structured prior precipitate substitution fluctuate microscopic ordered migration fitting 

分 类 号：TG115[金属学及工艺—物理冶金]