SiOC ceramics with ordered porosity by 3D-printing of a preceramic polymer

Ceramic parts possessing an ordered porosity were produced for the first time by powder-based three-dimensional printing of a preceramic polymer followed by pyrolysis in an inert atmosphere. The main parameters involved in the process were investigated, and the precision of the printed and ceramized parts was assessed by means of scanning electron microscopy and micro computed tomography. The influence of two different printing solvents was investigated and the use of a mixture of 1-hexanol and hexylacetate in particular allowed the production of parts with a relative density of 80% both in the polymeric and in the ceramic state. The mixing of a cross-linking catalyst directly with the printing liquid greatly simplified the process, minimizing the necessity of preprocessing the starting powder. Three-dimensional printing of a preceramic polymer not containing any inert or active fillers was proved to be a feasible, convenient and precise process for the production of porous ceramic possessing a complex, ordered structure, such as stretch-dominated lattices.