Structural, mechanical, electronic properties and Debye temperature of tungsten-technetium alloy: A first-principles study

Abstract

In this paper, we focus on the investigation of the crystal structure, mechanical properties, electronic properties and Debye temperature of tungsten-technetium alloy based on the first principles method. The configurations investigated are W15Tc1, W14Tc2, W12Tc4 and W8Tc8 alloys, respectively. The results show that the tungsten-technetium alloy still maintains a cubic lattice. The lattice constant of tungsten-technetium alloy is lower than that of pure W due to the atomic radius of technetium is smaller than that of tungsten. The formation energy analysis shows that the thermodynamic stability of tungsten-technetium alloy decreases with the increasing technetium concentration. By analyzing the elastic constant, elastic modulus and other mechanical parameters, the mechanical strength of tungsten-technetium alloy is weaker than that of pure tungsten. However, the B/G ratio and Poisson's ratio of tungsten-technetium alloy are greater than that of pure tungsten, which means that Doping technetium can improves the ductility of pure tungsten. In addition, the anisotropy, melting point and hardness, and Debye temperature of tungsten-technetium alloy is also discussed.