Polysilazane-derived SiCN ceramics-based layerless printing

In the process of light curing printing, layer steps are formed in the stacking direction. As these steps, i.e., by-products, affect the accuracy and quality of the printed surface significantly, avoiding their formation during printing is a prominent research topic. In this study, we propose a layerless printing method.Layerless printing uses the inhibition effect of oxygen on the polymerization reaction of ceramic precursor photosensitive resins, construct the oxygen inhibition layer during the printing process. We control the oxygen inhibition layer to weaken/eliminate the steps. In layerless printing, the high viscosity ceramic precursor photosensitive resin reduces the viscosity by heating up to make the fluidity of the material meet the printing conditions.The ceramic material can be realized straight-walled layerless in the z direction with a traditional layer thickness (100 µm). Furthermore, after pyrolysis of the printed ceramic precursor structure,the ceramic structure continued to retain zero layer steps.The result is that layerless printing reduced the surface roughness of the ceramic by 86.4%, the hardness and modulus of the ceramic were increased by approximately 10%, and the ceramic lattice of layerless printing was more uniformly stressed when subjected to compression stress.