An atomistic study of the newly-developed single-phase refractory high entropy alloy of TiZrVMo: Defect accumulation and evolution under tensile deformation

For the very first time, novel refractory high entropy alloys (RHEAs) of the Ti-Zr-V-Mo system with a single bcc solid solution structure have been predicted and confirmed by molecular dynamics, resulting in twelve new compositions with a single bcc structure here. For the equiatomic RHEA of TiZrVMo specifically, the tensile deformation behavior and underlying mechanism were studied by molecular dynamic simulations. Except for the dislocation toughening and stacking fault formation, the simulation revealed that the bcc to fcc and hcp phase transformation occurred during the plastic deformation of the RHEA, which was also reversible after the tensile failure. This work provides a solid theoretical reference for the composition design and ductility understanding for the development of RHEAs in practical applications.

Automated summary

Novel refractory high entropy alloys (RHEAs) of the Ti-Zr-V-Mo system with a single bcc solid solution structure were predicted and confirmed for the first time using molecular dynamics, resulting in twelve new compositions with a single bcc structure. Molecular dynamic simulations were conducted to study the tensile deformation behavior and mechanism of the equiatomic RHEA TiZrVMo, revealing dislocation toughening, stacking fault formation, as well as reversible bcc to fcc and hcp phase transformations during plastic deformation. This work provides important theoretical insights for composition design and ductility understanding of RHEAs in practical applications.