Modelling of δ-ferrite transformation effect on the sintering behaviour of 316L binder jetted components

Paper i proceeding, 2022

The main objective of this study is to develop a simulation methodology that accounts for phase transformation (δ-ferrite) during the sintering of 316L stainless steel binder jetted (BJ) components. The model was based on the continuum theory of sintering develop by Skorohod and Olevsky. Dilatometry sintering tests at different heating rates up to 1370°C were performed. The constitutive parameters for the sintering model were obtained by dilatometry data analysis. Dilatometry results at different heating rates showed minor influence of the δ-ferrite transformation kinetics on the material viscosity. Thus, a new temperature-dependent material viscosity function was proposed to include the δ-ferrite transformation. The new model proposed was used to predict the densification behaviour of 316L BJ samples subjected to dilatometry experiments at different temperatures and times. The influence of δ-ferrite on the densification was accurately predicted for the material and sintering conditions studied.