LENS Ti-6Al-4V alloy material properties determination for LS-Dyna package

Abstract

A procedure for determining the material properties of LENS Ti-6Al-4V is presented based on experimental uniaxial tensile tests with an extensometer. The elasto-plastic constitutive model with stress vs. effective plastic strain curve were selected in the study. In the first stage, the experimental uniaxial tensile tests of the specimens manufactured from Ti-6Al-4V alloy powder by LENS were performed on a universal strength machine. Based on the experimental tests material properties of the samples were evaluated and correlated. The proper methodology of calculating the values of effective plastic strain and effective plastic failure strain used in the selected constitutive models was emphasized and discussed. Correlated material properties were validated based on the static experimental compression test of a honeycomb cellular structure manufactured from Ti-6Al-4V alloy powder by LENS. The comparison of the results of numerical simulations and experiments showed reasonable similarity only for the first stage of deformation. Finally, adopting the elasto-visco-plastic constitutive model with the included damage resulted in an excellent reproduction of the force vs. displacement curve, deformation and failure of the honeycomb structure.