Phase Field Simulation of Dendritic Solidification of Ti-6Al-4V during Additive Manufacturing Process

Abstract

In this study, the phase field method is applied to simulate the phase transformation of Ti-6Al-4V from liquid phase to solid phase during solidification. The simulated results show the dendritic arms grow along the direction of the heat flow. Droplets are found formed inside the dendrites. Solute enriches in the liquid near the dendritic tips and between the dendritic arms. The effects of various processing parameters, including local temperature gradient, scan speed, and cooling rate, on dendrites morphology and growth velocity are studied. The results show that the higher temperature gradient, scan speed, and cooling rate will result in smaller dendritic arm spacing and higher growth velocity. The simulated dendritic morphology and arm spacings are in good agreement with experimental data and theoretical predictions.