摘要
为设计和开发具有优异力学性能的镁基纳米结构合金,本研究利用Voronoi几何方法构造了晶粒随机取向的纳米多晶镁模型,利用分子动力学软件实现了不同条件下纳米多晶镁的压缩模拟,借助可视化软件对模拟结果进行了相关分析。结果表明:随着温度升高,晶粒由细化转变为融合长大;压缩应变率影响晶粒细化的时间,压缩应变率增大,晶粒内部原子仍保持原有结构,只有晶粒边缘处原子位置移动,晶粒细化较晚发生,屈服强度增大,极限应变减小,弹性模量增大;纳米多晶镁中原子位置发生偏移,更易形成fcc结构,产生Shockley不全位错,Shockley不全位错与fcc结构的增长规律呈正比例。
To design and develop magnesium-based nanostructured alloys with excellent mechanical properties,a model of nanocrystalline magnesium with random grain orientation was constructed by the Voronoi geometry method.The compression simulation of nanocrystalline magnesium under different conditions was realized by molecular dynamics software.The simulation results were analysed by visualization software.The results show that with the increase of temperature,the grain size changes from refinement to fusion growth.The compression strain rate affects the time of grain refinement.With the increase of compression strain rate,the atoms in the grain still keep the original structure,only the atoms at the edge of the grain move,the grain refinement occurs later,the yield strength increases,the ultimate strain decreases,and the elastic modulus increases.The shift of atomic position in nano polycrystalline magnesium makes it easier to form fcc structure,resulting in Shockley incomplete dislocation,which is in positive proportion to the growth rule of fcc structure.
作者
杨千华
薛春
楚志兵
李玉贵
马立峰
Yang Qianhua;Xue Chun;Chu Zhibing;Li Yugui;Ma Lifeng(College of Materials Science and Engineering,Taiyuan University of Science and Technology,Taiyuan 030024,China;College of Mechanical Engineering,Taiyuan University of Science and Technology,Taiyuan 030024,China)
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2022年第4期1293-1303,共11页
Rare Metal Materials and Engineering
基金
国家重点研发计划(2018YFB1307902)
国家自然科学基金(U1710113)
山西省研究生联合培养基地人才培养项目(2018JD33)
山西省优秀青年基金(201901D211312)
山西省高等学校科技成果转化培育项目(2019KJ028)
山西省研究生教育创新计划(2019SY482)。
关键词
纳米多晶镁
分子动力学
压缩变形
Shockley不全位错
nanocrystalline magnesium
molecular dynamics
compression deformation
Shockley incomplete dislocation
