摘要
采用基于投影缀加波赝势和广义梯度近似的第一性原理计算方法计算FCC结构Fe以及3种Fe-Cu无序固溶体合金(Cu原子摩尔分数分别为25%、37.5%和50%)的基态性质、弹性常数以及电子结构,其中Fe-Cu无序固溶体合金采用特殊准随机结构模型进行计算。能量计算结果表明:FCC结构Fe存在无磁、低铁磁以及高铁磁性3种状态,而FCC结构Fe-Cu无序固溶体合金只存在无磁与高铁磁性两种状态。高铁磁性FCC结构Fe不满足Born弹性稳定性准则,铁磁性FCC结构Fe-Cu无序固溶体合金的弹性稳定性随着Cu含量的增加而增加;当Cu原子的摩尔分数不低于37.5%时,Fe-Cu无序固溶体合金满足Born弹性稳定性准则,此时合金以亚稳态形式存在。
The first-principles method based on projector augmented wave pseudo-potential and generalized gradient approximation was employed to calculate the ground state properties, elastic constants and electronic structure of face-centered cubic （FCC） Fe and Fe-Cu random solid solution alloys with Cu contents of 25%, 37.5% and 50% （mole fraction）. The special quasirandom structure （SQS） models were selected as the computational models for FCC Fe-Cu random solid solution alloys. The calculated total energies show that a nonmagnetic, a low ferromagnetic and a high ferromagnetic state are obtained in the FCC Fe, whereas a nonmagnetic state and a high ferromagnetic state exist in the ferromagnetic FCC Fe-Cu random solid solution alloys. The high ferromagnetic FCC Fe does not satisfy Born＇s criterion of elastic stability. The elastic stability of ferromagnetic FCC Fe-Cu random solid solution alloys increases with increasing the Cu content. When the Cu content is not less than 37.5%（mole fraction）, the ferromagnetic FCC Fe-Cu random solid solution alloys satisfy Born＇s criterion of elastic stability, and can exist as the metastable phases.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2012年第9期2522-2528,共7页
The Chinese Journal of Nonferrous Metals
基金
国家自然科学基金资助项目(50931003
50871065)
上海市科委资助项目(09JC1407200
10DZ2290904)
