Mechanical properties and microstructures of 3D printed bulk cordierite parts

In this study, digital light processing (DLP) 3D printing technology is used to prepare cordierite ceramic parts. The quality of the as-printed and as-sintered samples including dimensional accuracy, volume shrinkage, porosity and mechanical properties are determined. The influence of particle size of the prepared cordierite slurries, the predefined sliced layer thickness and the exposure time on the sample quality are evaluated via orthogonal experiments. The study shows that the particle size plays a crucial role in the quality and performance of the bulk samples. Smaller particles often lead to larger volume shrinkage and hence lower porosity. As a result, higher mechanical performance can be reached. Distinct features of cracks are demonstrated on different surfaces of the as-printed samples. Sintering process is found to be responsible for the favorable crack healing. Joint effect of porosity and cracks is believed to account for the mechanical properties measured at different length scales.