Laser speckle photometry investigation of the thermal conductivity of 3D printed ceramic green bodies using multi material jetting

Additive Manufacturing (AM) of high-performance materials is becoming more and more established in the market. Especially the field of technical ceramics shows an increasing need for monitoring the manufacturing process in order to identify defects that can be introduced into the component at an early stage and to remedy them if necessary. Optical methods are perfectly suited for in-situ monitoring of ceramic manufacturing as they are fast and contactless. This paper presents the Laser Speckle Photometry (LSP) as non-destructive approach for evaluating the material quality and process stability in Multi Material Jetting technology (CerAM MMJ). This method allows an examination of the droplet geometry as well as a characterization of their cooling and solidification behavior. Consequently, conclusions can be drawn about the used process setup and the current process stability, to improve the manufacturing quality and reproducibility. The investigation of the surface quality and evaluation temperature distribution of the first three layers printed by using CerAM MMJ technology is presented in this paper. A developed concept and ideas for evaluating the process stability of CerAM MMJ by LSP are shown.