| Abstract Scope |
A family of ternary carbides and nitrides, referred to as MAX phases, possess unique set of properties. These are light, stiff, thermodynamically stable and refractory, like ceramics, but damage-tolerant, pseudo-ductile at high temperatures and readily machinable like metals. Prior works have shown that polycrystalline MAX phases exhibit a range of deformation and failure mechanisms, such as crystallographic slip, ripplocation, twist, delamination and kinking. Here, we aim to correlate the single crystal level mechanical response of MAX phases to the overall mechanical response of the polycrystalline aggregate. To this end, micropillars are extracted from grains of know orientations using FIB milling and are subsequently deformed under compression using a flat-punch nanoindenter. The mciropillar experiments are complemented with novel in-situ SEM indentation experiments on single crystals of MAX phases. Our results shed new lights on the activation of various competing deformation and failure mechanisms in MAX phases at the single crystal level. |