Shuffling pathway of anti-twinning in body-centered-cubic metals

Hongxian Xie, Gaobing Wei, Jun-Ping Du, Akio Ishii, Guanghong Lu, Peijun Yu, Shigenobu Ogata

Scripta Materialia, 222, 114999

https://doi.org/10.1016/j.scriptamat.2022.114999

In this study, anti-twinning and deformation twinning of body-centered-cubic (BCC) metals under shear loading in the anti-twin direction were examined. Molecular dynamics simulations of BCC Ta showed both the existence of anti-twinning and a novel two-layer-by-two-layer anti-twinning mechanism consisting of a staggered shuffle sliding of {112} atomic planes in the [111¯] and [1¯1¯1] directions, generating finite shear displacement along the anti-twin direction. The density functional theory multi-dimensional interlayer slipping energy landscape of the newly observed anti-twinning process has a lower energy barrier for both twin nucleation and growth than the recently proposed layer-by-layer anti-twinning process.