Additive Manufacturing of Tailored Macroporous Ceramic Structures for High-Temperature Applications

Macroporous ceramic materials are ubiquitous in numerous energy-conversion and thermal-management systems. The morphology and material composition influence the effective thermophysical properties of macroporous ceramic structures and interphase transport in interactions with the working fluid. Therefore, tailoring these properties can enable significant performance enhancements by modulating thermal transport, reactivity, and stability. However, conventional ceramic-matrix fabrication techniques limit the ability for tailoring the porous structure and optimizing the performance of these systems, such as by introducing anisotropic morphologies, pore-size gradations, and variations in pore connectivity and material properties. Herein, an integrated framework is proposed for enabling the design, optimization, and fabrication of tailored ceramic porous structures by combining computational modeling, mathematically defined surfaces, and lithography-based additive manufacturing. The benefits of pore-structure tailoring are illustrated experimentally for interstitial combustion in a porous-media burner operating with a smoothly graded matrix structure. In addition, a remarkable range of achievable thermal conductivities for a single material is demonstrated with tuning of the fabrication process, thus providing unique opportunities for modulating thermal transport properties of porous-ceramic structures.