Influence of directional strength-to-stiffness on the elastic–plastic transition of fcc polycrystals under uniaxial tensile loading

Crystal-based finite element simulations have been conducted on virtual face-centered cubic polycrystals under uniaxial tensile loading to study the influence of single crystal elastic anisotropy on the elastic–plastic transition behavior exhibited by the lattice strains. The lattice strain response is examined for different sets of crystals corresponding to different crystallographic fibers. The lattice strain response observed in the elastic–plastic transition is related to crystals associated with different crystallographic fibers yielding on average at different levels of the macroscopic stress. The lattice strain behavior is determined by a combination of the elastic and plastic anisotropies of the single crystals, which is quantified using the directional strength-to-stiffness ratio. The directional strength-to-stiffness ratio for a single crystal and a crystallographic fiber are introduced and they are used to explain the deviation of the lattice strains from linear behavior in the elastic–plastic transition leading up to fully developed plasticity.