Modelling the thermal behaviour of Ti6Al4V sintered powder bed in electron beam powder bed fusion (EB-PBF)

The understanding of thermal behaviour of the sintered powder is a crucial feature in the electron beam powder bed fusion (EB- PBF) process. Accurate analyses may help optimise the process, manage smoke sensitivity materials, and give precious inputs for EB-PBF process modelling and simulation. The major issue in obtaining such kind of information is related to the working conditions of EB-PBF: high temperature and vacuum environment. Moreover, the powder bed should be considered a porous material. Using ad-hoc designed samples and experiments, this work presents an analysis of the thermal behaviour of the Ti6Al4V sintered powder in the EB-PBF process. An experimental campaign has been carried out to evaluate the variation of thermal conductivity of Ti6Al4V sintered powder with the powder thickness and the temperature up to 800°C, which corresponds to the common working temperature for processing Ti6A4V by EB-PBF