The effect of magnetostructural coupling on mechanical behaviors in CrN

The stiffness variations and their underlying mechanisms in CrN, a leading material for applications in coating technology, have been studied using the density functional theory. We find a sharp reduction of incompressibility but a drastic enhancement of shear stiffness across the magnetostructural transition from the cubic paramagnetic phase to the orthorhombic antiferromagnetic one. By establishing an interaction model, we explicitly elucidate that such unusual mechanical behaviors originate from the strong interplay between spin ordering and crystal structure.