Twinning dynamics in nanoscale body-centered cubic tungsten

The non-planar core structure of screw dislocations in body-centered cubic (BCC) metals strongly influences its twinning dynamics, resulting in a minimum embryo size of six-layers {112} planes and discrete three-layers thickening behavior. By considering the energetically-stable three-layers zonal dislocation as a unit of twinning front, we rationalize such discrete twinning behavior to the two units for twin embryo and one unit for growth, in consistent with the description of classical twinning theory.

Automated summary

The non-planar core structure of screw dislocations in bcc metals strongly affects the twinning behavior, leading to the formation of minimum six-layer {112} planes as embryos and discrete three-layer thickening. By considering the energetically-stable three-layers zonal dislocation as a unit, the study explains the discrete twinning behavior in consistent with the classical twinning theory.