A Generalization of the von Mises Criterion for a Single Crystal with a Hexagonal Crystal Lattice

Abstract

A natural generalization of the von Mises flow criterion is obtained taking into account anisotropy on single-crystal materials with a hexagonal crystal lattice. Boundary-value problems are posed for plane deformation by compression with back pressure, for uniaxial tension, compression, and for pure shear. A special case of solving boundary value problems for hexagonal magnesium with a purity of 99.9% at room temperature is considered. The values of coefficients included in the fluidity function and their errors are determined. The calculated and experimental data σ_0.2% for magnesium single crystals of various orientations are compared.