Fabrication techniques for making bodies of designed, including graded, pore structures of interest for various catalytic, sensor, electrical, and some possible structural uses are reviewed. Factors such as the amount and character of porosity are addressed along with gradients of pore structure and of the mixes of pore structures are considered. Emerging methods such as solid free form fabrication (SFF), for growing porous structures in some single crystals, and methods of special pore structure fabrication such as electrophoretic deposition are discussed along with techniques for more typical fabrication of pore structures and aspects of their practicality. Typical fabrication methods include limited sintering, removal of fugitive material, honeycomb extrusion, foaming, and more diverse techniques of making various solid or porous particles by conventional fabrication that can then be formed and bonded to produce a variety of bodies of mixed porous structures. Some other less developed fabrication techniques are also noted.
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