Deformation induced anisotropic responses of Ti–6Al–4V alloy. Part I: Experiments

Abstract

The anisotropic thermo-mechanical behaviors of an electron beam single melt Ti–6Al–4V alloy over a wide range of strain rates from quasi-static to dynamic regimes, and at various temperatures from 233 to 755K, are reported. The anisotropic responses are determined along different directions (the rolling, the transverse-to-rolling and the thickness directions). Measured responses are presented along these directions during uniaxial compression and tension loadings. Results are also given for behaviors under low confining pressures. Along with positive strain rate sensitivity and negative temperature dependency, the responses along the thickness and transverse to rolling direction are found to be close to each other. Along the rolling direction, it is much higher than the other two directions. The equivalent stress–strain curves are found to be independent of the confining pressure. The Khan–Huang–Liang (KHL) phenomenological model is used to predict the observed anisotropic thermo mechanical behaviors. A systematic method is employed to determine the model material constants utilizing the experimental data. By using the calibrated material constants, the capability of the constitutive model to predict thermo mechanical response of the alloy is evaluated by comparison of the numerical simulations and experimental observations. It is found that there is a close agreement between the simulated results and the experimental observations.