Investigation on curing strategies for metal binder jetting with Ti-6Al-4V

Abstract

Metal binder jetting is a promising manufacturing technology that holds the potential to be a future competition technology to classic laser based additive manufacturing processes. In contrast to these technologies, however, metal binder jetting is much less mature. While sintering and debinding are already well known due to the spread of metal injection molding and powder deposition by laser powder bed fusion and its related processes, the often-neglected curing step represents a major challenge in process control. This study was therefore the first comprehensive investigation into the curing of metal binder jetting green parts from Ti-6Al-4 V powder with a powder size distribution below 25 µm. It was shown that the curing step has only a minor effect on the green part quality (surface roughness and density), but at the same time has a decisive influence on the green strength. In addition, position-dependent effects for the green density were detected, which indicate insufficient curing in the outer areas of the print box.