Processing and Mechanical Properties of Microcellular Ceramics

Recently, a novel processing route for fabricating microcellular ceramics has been developed. The strategy for making the microcellular ceramics involves: (i) forming some shapes containing a mixture of preceramic polymer, expandable microspheres and optional fillers by a conventional ceramic forming method, (ii) foaming the compact by heating, (iii) cross-linking the foamed body, and (iv) transforming the foamed body into microcellular ceramics by pyrolysis. The flexural strength and compressive strengths of the microcellular ceramics were investigated; values up to 30 MPa and 100 MPa, respectively, were obtained at room temperature. The superior mechanical properties were attributed to homogeneous distribution of cells in microcellular ceramics.