Ideal tensile strength of cubic crystals under superimposed transverse biaxial stresses from first principles

Abstract

Elastic response and strength of perfect crystals is calculated for triaxial loading conditions from first principles. The triaxial stress state is constituted by uniaxial tensile stress and superimposed transverse biaxial stresses. The maximum uniaxial tensile stress is evaluated as a function of the transverse stresses. Results for eight crystals of cubic metals and two orientations ($⟨110⟩$ and $⟨111⟩$) of the primary loading axis are presented and compared with data for $⟨100⟩$ direction of loading. Obtained results show that, within a studied range of biaxial stresses, the maximum tensile stress monotonically increases with increasing biaxial tensile stress for most of the studied metals. Within a certain range, the dependence can be mostly approximated by a linear function.