Innovative High-Temperature Ceramic Coatings via Inkjet printing of polysilazane/MoSi2 Inks

Abstract:
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 ink for 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 degC in an inert atmosphere, resulting in the formation of defect- and crack-free coatings.The layer thicknesses range from 0.2 micrometerm to 2 micrometerm. 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.