Analysis and optimisation of parent grain reconstruction for additively manufactured Ti-6Al-4V

During solidification processing, most common titanium alloys solidify as high-temperature parent phase and it subsequently transforms into the room-temperature child phase. This parent to child transformation occurred as a solid-state transformation. Even though the parent phase is not observable at room temperature, it is considerably associated with solidification defects such as porosity. Parent grain reconstruction based on Burgers orientation relationship, which shows the crystallographic relationship between two phases, has been applied to examine the high temperature and transitional parent phases of titanium alloys and steels. This contribution presents the reconstructed high temperature parent phase and the sensitivity analysis related to a series of parameters for three crucial parent phase reconstruction steps for additively manufactured titanium alloy Ti-6Al-4V. The analysis examines the reconstruction, merging of very small and neighbouring grains together, and finally cleaning of inclusive noise, which referred as inclusions during the rendering process of the parent phase. The analysis offers an instruction for threshold selection that enables optimised parent phase reconstruction.