Mechanical behavior of zirconium hydride phases: insights from molecular dynamics based simulations

Abstract

This article aims to study the mechanical behavior of zirconium hydride phases, including γ-ZrH, δ- ZrH1.5, and ε-ZrH2. Atomistic simulations were performed to analyse the uni-axial tensile behaviour of zirconium (Zr) and zirconium hydrides in conjunction with the deformation governing mechanism. The mechanical behavior of Zr and zirconium hydrides was studied with the help of stress-strain curves, dislocation dynamics, and von Mises stress distribution. The atomistic simulation results were subsequently compared with the existing trends in the literature. The hydrogen concentration significantly influences the mechanical properties and deformation governing behaviour of zirconium hydrides. Hydride precipitate in the Zr matrix is a barrier to the glissile dislocations, leading to hydrogen embrittlement. This phenomenon intensifies with hydride size and hydrogen concentration, and the effect is more pronounced at lower temperatures.