The effect of Al and Cr elements on the oxidation resistance of MoSi2 via first-principles calculation

作     者：Liwu Jiang Meiling Wu Peng Shi Chuanhui Zhang 

作者机构：National Center for Materials Service Safety University of Science and Technology Beijing NCS Testing Technology Co. Ltd. Beijing Institute of Aeronautical Materials 

出 版 物：《Progress in Natural Science:Materials International》 (自然科学进展·国际材料(英文))

年 卷 期：2019年第29卷第1期

页      面：65-70页

核心收录：

学科分类：081704[工学-应用化学] 07[理学] 070304[理学-物理化学(含∶化学物理)] 08[工学] 0817[工学-化学工程与技术] 0703[理学-化学] 070301[理学-无机化学] 

基　　金：supported by the National Natural Science Foundation of China (Grant nos. 51471022, 51601183) the Fundamental Research Funds for the Central Universities (Grant nos. FRF-BD-17-001A, FRF-GF-17-B15, FRF-TP-18-011A3) the National Key R&D Program of China (Grant no. 2017YFB0203703) 

主　　题：MoSi2 Alloying element Impurity Substitution Oxidation resistance 

摘      要：The properties of structure, energy and oxidation resistance of interstitial and substitutable MoSi2systems have been investigated using the density functional theory. The calculated lattice constants for pristine MoSi2confirm the early experimental results. In the interstitial MoSi2, the impurity energy of O atom was computed for the stable interstitial site in the systems. The results reveal that the O atom prefers to occupy the Oct2 site with the lowest impurity energy. In the substitution MoSi2, the Si sites tend to be substituted with Al and Cr atoms,whereas, Mo sites do not behave like the Si sites. The co-substitution of Al/Cr atoms and the direction of the O diffusion in MoSi2have been analyzed as well. The results from electronic structural analysis indicate that the SiO bond is the main factor to inhibit the diffusion of O, and the alloying elements of Al and Cr contribute to the oxidation resistance of MoSi2.