CERAMICS INTERNATIONAL Available online at www.sciencedirect.com Ceramics International ] (]]]]) ]]]–]]] Review paper Processing and properties of advanced porous ceramics: An application based review E.C. Hammel, O.L.-R. Ighodaro, O.I. Okoli n High-Performance Materials Institute, FAMU-FSU College of Engineering, 2525 Pottsdamer Street, Tallahassee, FL 32310, United States Received 29 April 2014; received in revised form 18 June 2014; accepted 18 June 2014 Abstract Ceramics with engineered porosity are promising materials for a number of functional and structural applications including thermal insulation, filters, bio-scaffolds for tissue engineering, and preforms for composite fabrication. In this application based review of advanced porous ceramics, the microstructure of porous components is discussed in terms of the necessary features required to achieve the ideal properties for the intended application. The processing methods that are capable of producing the required microstructure are addressed. Those methods which allow the pore structure to be tailored or controlled are considered the most favorable processing techniques. & 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved. Keywords: B. Porosity; B. Microstructure – final; E. Functional applications; E. Structural applications Contents 1. Introduction ................................................................................... 2 1.1. Overview of processing techniques .............................................................. 2 2. Porous ceramics for thermal insulation ................................................................. 3 2.1. Microstructure – processing relationship........................................................... 3 2.2. Freeze casting process for thermal insulation ....................................................... 4 3. Porous ceramics for filtration purposes ................................................................. 4 3.1. Water filters ............................................................................. 4 3.2. Hot gas filters ............................................................................ 5 3.3. Molten metal filters ........................................................................ 6 3.4. Filter operation ........................................................................... 6 3.5. Processing of ceramic filters................................................................... 7 3.5.1. Freeze casting process for filter fabrication.................................................... 7 4. Porous ceramics for bio-scaffolds in tissue engineering applications ............................................. 8 4.1. Processing of ceramic bio-scaffolds .............................................................. 10 4.1.1. Direct AM fabrication................................................................. 11 4.1.2. Indirect AM fabrication................................................................ 11 5. Porous ceramic preforms for fabrication of ceramic–metal composites ........................................... 13 www.elsevier.com/locate/ceramint http://dx.doi.org/10.1016/j.ceramint.2014.06.095 0272-8842/& 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved. Abbreviations: AM, additive manufacturing; CAD, computer aided design; CFFs, ceramic foam filters; DPFs, diesel particulate filters; IPCs, interpenetrating composite; POU, point-of-use; SEM, scanning electron microscope; TBA, tert-butyl-alcohol n Corresponding author. Tel.: þ1 850 410 6352; fax: þ 1 850 410 6342. E-mail address: ookoli@fsu.edu (O.I. Okoli). Please cite this article as: E.C. Hammel, et al., Processing and properties of advanced porous ceramics: An application based review, Ceramics International (2014), http://dx.doi.org/10.1016/j.ceramint.2014.06.095