Atomic-scale observation of nucleation- and growth-controlled deformation twinning in body-centered cubic nanocrystals.

ABSTRACT: Twinning is an essential mode of plastic deformation for achieving superior strength and ductility in metallic nanostructures. It has been generally believed that twinning-induced plasticity in body-centered cubic (BCC) metals is controlled by twin nucleation, but facilitated by rapid twin growth once the nucleation energy barrier is overcome. By performing in situ atomic-scale transmission electron microscopy straining experiments and atomistic simulations, we find that deformation twinning in BCC Ta nanocrystals larger than 15 nm in diameter proceeds by reluctant twin growth, resulting from slow advancement of twinning partials along the boundaries of finite-sized twin structures. In contrast, reluctant twin growth can be obviated by reducing the nanocrystal diameter to below 15 nm. As a

SUBMITTER: Zhong L 

PROVIDER: S-EPMC10791697 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature