Calculations of stress-strain curve and stress and strain distributions for an α-β Ti8Mn alloy

Abstract

Tensile stress-strain curves of an α-β Ti8Mn alloy were calculated by the finite element method (FEM) using the stress-strain curves and appropriate volume fractions of each phase. The calculated curve lies below the experimental curve, and this may be due to finer grain sizes in the Ti8Mn alloy and the contribution of the interface phase, which were not considered. Stress gradients were found in both α and β phases and the nature of the stress gradient was found to depend on α particle shape. In some locations higher stresses were found in α near the interface. In β, the stresses were generally higher near the interfaces. For the range of stresses used in the calculations, strains were higher in α than in β but stress-strain behavior was found to be closer to constant strain- than to constant stress combinations of α and β stress-strain curves. The implications of stress gradients with regard to hydrogen flow, and hydrostatic stresses in regard to void formation at α-β interfaces are considered.