Regular Article

Pressure effect on the mechanical and electronic properties of the tungsten triboride doped with iron: a first-principles study

¹ Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, México CDMX 04510, Mexico
² Facultad de Ciencias, Universidad Nacional Autónoma de México, México CDMX 04510, Mexico
³ Escuela Superior de Ingeniería Mecánica y Eléctrica-Culhuacán, Instituto Politécnico Nacional, México CDMX 04430, Mexico

^a e-mail: rauleg@unam.mx

Received: 9 April 2020
Received in final form: 3 July 2020
Accepted: 16 July 2020
Published online: 16 September 2020

Abstract

The crystal structure, mechanical, and electronic properties of W_0.71Fe_0.15B₃ under pressure were studied by first principles. Our results show that the structural parameters obtained by geometry optimization are in agreement with other experimental and theoretical results; the main effect of pressure on the structure is compression along the c-axis. The independent elastic constants, mechanical modules, and the Debye temperature increase under pressure, whereas the hardness decreases. Born’s structural stability criteria shows that the structure with space group P6₃/mmc is mechanically stable up to 50 GPa; while, Pugh’s and Poisson criteria suggest a transition from brittle to ductile between 30 and 35 GPa. Finally, the density of states at the Fermi energy decreases and a charge transfer from W/Fe to B under pressure is determined.