Phase-field simulation of microstructure evolution of Ti–6Al–4V in electron beam additive manufacturing process

Abstract

Electron beam additive manufacturing (EBAM) is a relatively new technology to produce metallic parts in a layer by layer fashion by melting and fusing the metallic powders. Ti–6Al–4V is one of the most used industrial alloys used for aerospace and biomedical application. EBAM is a rapid solidification process and the properties of the build material depend on the solidification behavior as well as the microstructure of the build material. Thus, the prediction of part microstructures during the process may be an important factor for process optimization. In this study, a phase field model is developed for microstructure evolution of Ti–6Al–4V powder in EBAM process. FORTRAN code is used to solve the phase field equations, which incorporates the temperature gradient and solidification velocity as the simulation parameters. The effect of temperature gradient and the beam scan speed on microstructure is investigated through simulation. The simulation results are compared with the analytical model and experimental findings by measuring the spacing evolution under the solidification condition