Twinning-induced pseudoelastic behavior in (MoW)$_{85}$(TaTi)$_{7.5}$Zr$_{7.5}$

TL;DR

This study demonstrates temperature-dependent pseudoelastic behavior in a complex BCC alloy, driven by twinning mechanisms, with potential for high-temperature elastic recovery and isotropic deformation characteristics.

Contribution

It provides atomistic evidence of pseudoelasticity in a complex Mo-W-Ta-Ti-Zr alloy, expanding understanding beyond pure metals and simpler alloys.

Findings

Pseudoelasticity is temperature-dependent and aided by twinning.

The alloy exhibits isotropic pseudoelastic behavior under different loading directions.

Elastic strain recovery improves with temperature from 77 K to 1500 K.

Abstract

We provide a critical atomistic evidence of pseudoelastic behavior in complex solid-solution BCC Mo-W-Ta-Ti-Zr alloy. Prior to this work, only limited single-crystal BCC solids of pure metals and quaternary alloys have shown pseudoelastic behavior at low temperatures and high strain rates. The deformation mechanisms investigated using classical molecular simulations under tensile-compressive loading reveal temperature-dependent pseudoelastic behavior aided by twinning during the loading-unloading cycle. The pseudoelasticity is found to be independent of loading directions with identical cyclic deformation characteristics during uniaxial loading. Additionally, temperature variation from 77 to 1500 K enhances the elastic strain recovery in the alloy.