摘要
利用基于密度泛函理论的第一性原理方法,研究了钼元素掺杂前后α-Fe/NbC界面的黏附功、界面能、电子结构和成键特征等性质。考虑了2种不同原子的终端界面,并分析了6种Mo原子置换位置对α-Fe/NbC界面结构的影响。结果表明:C终端界面结构的稳定性比Nb终端界面的稳定性更强,而Mo原子进入界面NbC侧置换Nb原子形成的α-Fe/(Nb,Mo)C界面则表现出比未掺杂界面更好的稳定性。因此,Mo对NbC在铁素体中的形核有一定的促进作用。另外,6种界面的差分电荷密度、态密度和Milliken布居分析也解释了Mo能强化α-Fe/NbC界面的原因。
Work of adhesion,interfacial energy,electronic structure and bonding characteristics ofα-Fe/NbC interface before and after Mo doping were studied by the first-principle method based on density functional theory.Two kinds of interfaces with different atomic termination were considered,and the effects of six kinds of Mo atom positions on the properties ofα-Fe/NbC interface were investigated.The results showed that the stability of C-top interface structure was better than that of Nb-top interface,and theα-Fe/(Nb,Mo)C interface obtained by replacing the Nb atoms on the NbC side exhibited better stability compared with the clean interface.Therefore,Mo was favoarble for promoting the nucleation of NbC in ferrite.In addition,the difference charge density,density of state and Milliken analysis of above interfaces also explained the reason why Mo can enhance the strength ofα-Fe/NbC interface.
作者
程汉
陈万超
张恒华
CHENG Han;CHEN Wanchao;ZHANG Henghua(School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China)
出处
《上海金属》
CAS
北大核心
2020年第5期94-100,共7页
Shanghai Metals
关键词
碳化铌
界面能
钼
第一性原理
NbC
interfacial energy
Mo
first-principle
