Functionally graded ceramics by lithography-based ceramic manufacturing (LCM)

With the development of new industries and technological processes, the use of pure materials in sophisticated applications is declining due to the demand of conflicting property requirements in a single component. The interest on functionally graded ceramics (FGCs) that can be used under severe service conditions with high reliability has increased in parallel to the higher demand on complex advanced ceramics in various applications. Conventional methods are not totally capable of cost-effective fabrication of near-net shape FGCs with flexible and complex gradient designs. Lithography-based ceramic manufacturing (LCM) is an additive manufacturing (AM) method that works according to the principle of selective curing of photosensitive formulations utilizing the digital light processing (DLP) approach. The recently developed LCM multi-material printer allows fabrication of ceramic-ceramic and metal-ceramic combinations with high dimensional precision. Printing methodologies were developed to manufacture FGCs which show both discrete and continuous porosity gradient in parallel and perpendicular to the deposition direction. FGC combinations were produced by developing suitable suspensions, optimizing the debinding and sintering processes according to the single material thermo-elastic properties, design, and optimization of printing processes. The main challenges and future possibilities in realization of FGCs by LCM will be presented.