文摘
Capitalizing on density functional theory, the novel Si-Ge-based oxynitrides (SiGeN2O) have been studied in terms of mechanical and thermal properties. Regarding α- or β-SiGeN2O, the SiGeN2O exhibits smaller mechanical moduli, suggesting a compressible and soft material. Our calculated lattice constants of two SiGeN2O phases are very consistent with other values. In addition, the hardness for SiGeN2O is investigated in details according to different semi-empirical methods. The results indicate a small hardness of two phases of SiGeN2O. Furthermore, the mechanical anisotropy, Debye temperature and the minimum thermal conductivity of two SiGeN2O compounds are clearly estimated for both SiGeN2O compounds. It is found that the SiGeN2O compounds show low thermal conductivity, which is suitable to be used as a thermal barrier coating.
