Role of hydrogen on the structural stability, mechanical and thermodynamic properties of the cubic TM3Si silicides

Although the TM 3 Si silicides play an important role in transition metal silicides high-temperature materials, the hydrogenated mechanism of the cubic TM 3 Si is entirely unclear. To explore the hydrogenated mechanism, in this work, we apply the first-principles calculations to study the influence of hydrogen on the structural stability, mechanical and thermodynamic properties of TM 3 Si silicides. Based on the structural characteristic, four TM 3 Si silicides (Mo 3 Si, Nb 3 Si, Cr 3 Si and W 3 Si) and three hydrogen occupied models were considered. In particular, the influence of hydrogen on the stability, elastic properties, hardness, brittle-or-ductile behavior and Debye temperature of TM 3 Si was investigated. The result shows that the hydrogen is a thermodynamic stability in TM 3 Si because of the electronic interaction between hydrogen and TM 3 Si silicides. The thermodynamic stability of the hydrogenated TM 3 Si follows the order of Nb 3 Si