Ideal shear strain of metals and ceramics

TLDR

The study aims to determine the maximum shear strain a homogeneous crystal can withstand, a property the authors term shearability. The authors use density functional theory to analyze the stress–strain responses of 22 simple metals and ceramics. They find a shearability gap between metals and covalent ceramics, with metal shearability correlating with valence charge localization and directional bonding, ionic solids sometimes exceeding covalent ones, and the Frenkel model accurately predicting ideal shear strength when scaled by shearability.

Abstract

Using density functional theory we analyze the stress-strain responses of 22 simple metals and ceramics to determine the maximum shear strain a homogeneous crystal can withstand, a property for which we suggest the name shearability. A shearability gap is found between metals and covalent ceramics. Shearability of metals further correlates with the degree of valence charge localization and directional bonding. Depending on the deformation constraints, ionic solids may possess even larger shearability than covalent solids. The Frenkel model of ideal shear strength works well for both metals and ceramics when shearability is used in the scaling.