采用第一性原理方法,研究了α-Fe(001)/Mo2 FeB2(001)界面性能.建立了4种不同的原子堆垛方式界面模型,计算了其界面粘附功、界面结合能和断裂功.结果表明,以空心位置堆垛的Fe终端界面性能最稳定,而顶部位置的Fe+B终端界面性能最不稳定,两者的裂纹断裂均趋向于发生在基体相或硬质相内.在此基础上,进一步分析了空心位置Fe终端界面模型和顶部位置Fe+B终端界面模型的电子结构,电荷差分密度图显示在空心位置的Fe终端界面系统中,界面处Fe原子与Fe原子间形成金属键,界面处Fe原子与M o原子间形成金属键.在顶部位置的Fe+B终端界面系统中,界面处的Fe原子与B原子间形成共价键,但界面强度比空心位置的Fe终端界面系统低.分态密度显示界面处原子间重新排列,发生杂化,形成共价键,揭示了界面成键特性.%The interface performance of α-Fe(001)/Mo2 FeB2 (001) was studied based on the first-principles .Four different interface models of atom stacking were established ,and the interface adhesive work ,the binding energy and rupture work were calculated .The results show that the interface performance of Fe-terminated was most stable which was stacked by hollow position , the interface performance of Fe+B-terminated on the top was the worst stable .Both of the crack fractures were trended to occur at the substrate phase or the hard phase .Based on this ,the electron structure was further analyzed ,the charge density difference graph showed that in the interface system of Fe-terminated at the hollow position ,the metallic bond was formed between the Fe atom at interface and among the Fe atoms ,also the metallic bond was formed between Fe atom and Mo atom .On top of the interface system of Fe+B-terminated ,the covalent bond was formed between Fe atom and B atom ,the interface strength was lower than the one in the Fe-terminated interface system at hollow position .The partial density of state indicated the atoms at interfaces were rearranged , hybridization occurred ,and the covalent bond was formed ,which revealed the forming characteristic of the interface bond .
展开▼
