Cu50Ni50合金凝固过程中的空位捕获
Vacancy trapping during solidification of Cu50Ni50 alloy
张伯阳 1汪昊 1周涛 1吴永全1
作者信息
- 1. 上海大学材料科学与工程学院,上海 200444;上海大学省部共建高品质特殊钢冶金与制备国家重点实验室,上海 200444;上海大学上海市钢铁冶金新技术开发应用重点实验室,上海 200444
- 折叠
摘要
通过分子动力学(molecular dynamics,MD)模拟,研究了 Cu50Ni50合金在不同温度下凝固及其退火过程的空位捕获.结果发现:凝固过程中的空位捕获效应,即被捕获空位浓度的过饱和现象非常明显;随着凝固温度的降低,空位浓度显著上升,与平衡浓度随温度的变化规律正好相反;Cu50Ni50存在一个特征温度T*,在T＞T*浅过冷温度下,凝固速度随着凝固温度的降低快速增加,在T＜T*深过冷温度下,凝固速度随着凝固温度的降低缓慢下降,表明空位浓度并不是界面生长速度的单值函数;作为合金元素,Cu比Ni更倾向于形成空位原子(vacancy atom,VA).
Abstract
Molecular dynamics(MD)simulation was used to investigate the vacancy trap-ping during the solidification and annealing processes of Cu50Ni50 at different temperatures.The results showed that the vacancy trapping effect was very evident and the vacancy con-centration significantly increased with the decrease in temperature,opposite to the law that the equilibrium concentration changes with temperature.There was a characteristic temperature T*for which the solidification rate rapidly increased with the decrease of tem-perature at shallow undercooling when T＞T*but decreased slowly at deep undercooling when T＜T*,indicating that the vacancy concentration was not a monotonic function of the interface moving rate.In addition,as an alloy constituent,Cu was found to be a better vacancy atom(VA)than Ni.
关键词
分子动力学模拟/空位捕获/凝固温度/Cu50Ni50合金Key words
molecular dynamics(MD)simulation/vacancy trapping/solidification tem-perature/Cu50Ni50 alloy引用本文复制引用
基金项目
国家自然科学基金(52074178)
国家自然科学基金(51374141)
出版年
2024
NETL
NSTL
万方数据