First order pyramidal slip of 1/3 <1-210> screw dislocations in zirconium

TL;DR

This study uses atomistic simulations to investigate the pyramidal glide of screw dislocations in zirconium, revealing a metastable stacking fault that influences dislocation behavior.

Contribution

It demonstrates the existence of a metastable stacking fault in zirconium's pyramidal plane, providing new insights into dislocation mechanisms in hexagonal close-packed metals.

Findings

Identification of a metastable stacking fault in zirconium

Spontaneous formation of a metastable dislocation configuration

Insights into pyramidal slip mechanisms in zirconium

Abstract

Atomistic simulations, based either on an empirical interatomic potential or on ab initio calculations, are used to study the pyramidal glide of a 1/3 <1-210> screw dislocation in hexagonal close-packed zirconium. Generalized stacking fault calculations reveal a metastable stacking fault in the first order pyramidal {10-11} plane, which corresponds to an elementary pyramidal twin. This fault is at the origin of a metastable configuration of the screw dislocation in zirconium, which spontaneously appears when the dislocation glides in the pyramidal plane.