The mechanism of elastic and electronic properties of Tungsten Silicide (5/3) with vacancy defect from the first-principles calculations

The development prospects of transition metal silicon-based materials have received considerable attention. Tungsten-based silicides are one of the most important silicon-based high-temperature materials. Here, the mechanism of elastic and electronic properties of Tungsten Silicide (5/3) with vacancy defects was further studied using the first-principles approach. The vacancy formation enthalpy, elastic constants, elastic moduli, brittle/ductile behavior, hardness and electronic structure of the perfect W5Si3 and W5Si3 with vacancies were calculated and discussed, respectively. The result demonstrates that W5Si3 with W vacancies exhibit the better stability than W5Si3 with Si vacancies. Vacancy defects weaken the mechanical strength for the perfect W5Si3. The removal of the Si atoms makes W5Si3 with vacancies exhibit the better ductility than the parent W5Si3. The electronic structures explain the mechanism for structural stability and mechanics properties of W5Si3 by vacancy defects.