First-principles calculations on the mechanism of kink deformation in metallic crystals

Ito, Yuto*; Egusa, Daisuke*; Yamaguchi, Masatake   ; Abe, Eiji*

Among HCP metals, Zn and Cd, which exhibit high c/a ratios, exhibit a peculiar deformation mode with crystal rotation called kink deformation under conditions where the main slip system is suppressed. Although a model of kink deformation has been proposed based on collective rearrangement of dislocations, the details of the kink deformation have not been clarified. In this study, we evaluate the phonon dispersion relation using first-principles calculations for HCP metals under uniaxial compression in the basal plane, where kink deformation is known to occur, and verify the generalized stacking fault energy, which is considered important for characterization of dislocations.