Non-classical crystallographic slip in a ternary carbide - Ti2AlC

IMPACT STATEMENT This work elucidates single-crystal level non-classical deformation mechanism(s) of a MAX phase and unravels the observed extreme plastic anisotropy of MAX phases. Herein, we report on mechanical deformation of single-crystal Ti2AlC MAX phase using compression testing of micropillars with a range of crystallographic orientations. Our results show that depending on the crystallographic orientation, the Ti2AlC micropillars either undergo only non-classical (non-Schmid) crystallographic slip, non-classical crystallographic slip followed by cleavage or cleavage without any appreciable crystallographic slip. The non-classical crystallographic slip is found to be a result of the strong dependence of crystallographic slip on both, the resolved shear stress and the stress normal to the slip plane.