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本文采用平面波密度泛函理论研究了Mg(001)/ZrB2(001)界面的分离功、界面能和电子结构.首先通过界面结构优化可知,B终端的顶位界面结构几乎不发生改变;而B终端的桥位界面结构转变为B终端的中心位界面结构.另外,Zr终端的顶位界面结构和Zr终端的桥位结构都转变为Zr终端的中心位界面结构,新形成的B终端中心界面结构中的Mg–B键的长度、界面距离、分离功与初始的B终端中心界面结构几乎相同.B终端中心位界面结构有最大的分离功,同时有最小的界面距离,因此B终端中心位界面结构是最稳定的界面结构.次界面位置的分离功表明Mg(001)/Zr B2(001)界面增强了Mg端的结合强度,削弱了Zr B2端的结合强度.B终端中心位的界面结构和Zr终端中心界面可以自发形成是由于它们在富B和在贫B环境中分别有负的界面能.在B终端中心位和顶位界面结构中,界面处有共价键和离子键形成,而且B终端中心位界面结构的共价键方向性更强.结果表明,Zr B2颗粒可以用来增强Mg合金.
In this paper, the work function, interfacial energy and electronic structure of Mg (001) / ZrB2 (001) interface were studied by plane wave density functional theory. First, the interface structure optimization of B terminal almost did not change; The structure of the bridge interface of the terminal is transformed into the structure of the center interface of the terminal B. In addition, the top interface structure of the Zr terminal and the bridge structure of the Zr terminal are transformed into the center interface structure of the Zr terminal, and the newly formed B terminal center interface The structure of Mg-B bond length, interface distance, separation work and the initial B terminal center interface structure is almost the same .B terminal center interface structure has the largest separation work, with the minimum interface distance, so the B terminal center position The interface structure is the most stable interface structure. The work of separation at the secondary interface shows that the Mg (001) / Zr B2 (001) interface enhances the bond strength of the Mg end and weakens the bond strength of the Zr B2 end. Zr terminal center interface spontaneously formed because of their negative interface energies respectively in B-rich and B-poor environments.In the B-terminal center and top interface structures, covalent and ionic bonds are formed at the interface, Moreover, the covalent bond orientation of the B-terminal central interface structure is stronger.The results show that ZrB2 particles can be used to enhance the Mg alloy.