A comparative study on Johnson-Cook constitutive modeling for Ti-6Al-4V alloy using automated ball indentation (ABI) technique

In this study, automated ball indentation (ABI) technique has been employed to explore the flow behavior of Ti-6Al-4V alloy at low strain rates and elevated temperatures. Isothermal ABI tests have been performed in a wide range of temperatures (293 K, 493 K, 693 K, and 873 K) and strain rates (10−6, 10−5 and 10−4 s−1). Based on the experimental true stress-plastic strain data derived from the ABI tests, Johnson-Cook (J-C) constitutive model has been employed to predict the flow behavior of Ti-6Al-4V alloy at low strain rates and elevated temperatures. A comparative study has been made to verify the applicability of current J-C models at low strain rate based on finite element method (FEM). The results show that the predicted values by the Johnson-Cook constitutive model agree well with the experimental data, and the automated ball indentation (ABI) technique could give a precise prediction of the flow behavior of Ti-6Al-4V alloy at low strain rates and elevated temperatures.