摘要
利用分子动力学方法在不同温度下对含不同空位浓度的γ-TiAl合金进行拉伸模拟,分别研究了Ti空位和Al空位对材料力学性能的影响。研究结果表明:在温度为1K时,随着Ti和Al空位浓度的增加,材料的极限应力呈非线性下降。但是,含Ti空位的模型比含Al空位模型的极限应力下降的慢。这主要是由于γ-TiAl合金中Ti空位和Al空位的空位形成能的不同导致其扩散系数有较大差异。当温度在300~1100K时,屈服强度随温度的升高而降低,并且温度对势能的影响较大,温度越高,势能越大。
Molecular dynamic simulations were performed to study the effects of vacancies of both Ti and Al on the mechanical properties ofγ-TiAl alloy.The results show non-linear a decrease of ultimate stress with the increase in Ti and Al vacancy concentration,but the ultimate stress of the model with higher Ti vacancy tends to decrease slower than the one with higher Al vacancy.This is mainly due to the difference of vacancy formation energy of Ti and Al,and thus difference of diffusion coefficient,in theγ-TiAl alloy.When the temperature ranges from 300K to 1100K,the yield strength decreases with the increase of temperature.In addition,potential energy is affected by both temperature and vacancy concentration.The higher the temperature is,the larger the potential will be.
作者
李龙龙
冯瑞成
李海燕
寇佩佩
闫峰
LI Longlong;FENG Ruicheng;LI Haiyan;KOU Peipei;YAN Feng(School of Mechanical and Electronical Engineering,Lanzhou University of Technology,Lanzhou 730050,China;Key Laboratory of Digital Manufacturing Technology and Application,Ministry of Education,Lanzhou University of Technology,Lanzhou 730050,China)
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2020年第1期129-133,共5页
Journal of Materials Science and Engineering
基金
国家自然科学基金资助项目(51665030)
长江学者和创新团队发展计划资助项目(IRT_15R30)
甘肃省自然科学基金资助项目(17JR5RA114)
兰州理工大学博士基金资助项目
