A. Khecho - MS, School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran, Tehran, Iran
A. Ghaffari - Assistant Professor, School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran, Tehran, Iran
M. Behzadnasab - Assistant Professor, Faculty of Polymer Processing, Iran Polymer and Petrochemical Institute, Tehran, Tehran, Iran
M. Rahmat - Assistant Professor, Faculty of Polymer Processing, Iran Polymer and Petrochemical Institute, Tehran, Tehran, Iran

In ceramic additive manufacturing, it is important to fabricate parts with high solid contents to guarantee defect-free sintered parts. In stereolithography, low viscosity and especially shear-thinning behavior of the ink are the key factors in producing ceramic-resin parts. Therefore, there should be a correlation between solid loading and viscosity. In this study, Alumina-glass inks were printed using bottom-up and top-down approaches, and the rheological properties were investigated. The main objective of this study was to print a highly filled ceramic-resin part with a viscosity suitable for DLP printing. While use of suspensions with low viscosity was recommended for top-down digital light processing (DLP) printing, a new setup was designed to study the feasibility of the top-down approach for pastes for the top-down approach. According to the findings, ceramic-resin pastes with the solid content of maximum ۷۵ wt% and viscosity of ۴۷.۶۴ Pa.s at the shear rate of ۳۰ s-۱ were easily printable via our hand-made top-down DLP printer. However, it was not possible to print inks with solid contents more than ۶۰ wt% using the bottom-up DLP, mainly because the detachment force grew dramatically with an increase in viscosity.

Additive Manufacturing, ۳D Printing, DLP, Alumina, Rheology