Innovative High-Temperature Ceramic Coatings via Inkjet printing of polysilazane/MoSi$_2$ Inks

The exceptionally versatile processability of preceramic polymers makes these materials suitable for the use in additive manufacturing of ceramic components and coatings.In this study, a particle-filled and solvent-based inkfor inkjet printing was developed. The ink meets inkjet printing specifications for rheological and surface properties, as it displays Newtonian behaviour. Thermogravimetric analysis revealed a high ceramic yield of 88 %, which is attributable to the ceramic nanoparticles MoSi2. The nanoparticles were ball-milled and stabilised to achieve a submicron size and prevent agglomeration. The milling process was controlled by measuring the particle size distribution using dynamic light scattering. Inkjet-printed thin films and multilayers have formed homogeneous green bodies after UV curing. Subsequently, the thin films were pyrolyzed at 950 °C in an inert atmosphere, resulting in the formation of defect- and crack-free coatings.The layer thicknesses range from 0.2 µm to 2 µm. These thin films can be printed at high resolution, making them suitable for the use as interlayer dielectrics in MEMS applications and as high-temperature protective layers.