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Ti-Al porous intermetallic compounds were prepared by a simple and energy-saving process of thermal explosion (TE) reactions. The effects of the Ti/Al molar ratios (including Ti : Al ¼ 3 : 1, 2 : 1, 1 : 1, 1 : 2 and 1 : 3) on the temperature profiles, phase compositions, pore characteristics, density, expansion behaviors and oxidation resistance were investigated. The ignition temperatures were between 630-653 C and the combustion temperatures were between 737-1161 C, both of which are higher than the target furnace temperature. Porous Ti-Al alloys displayed a high open porosity of 35-56%. The pores were from non-fully dense green compacts and expansion behaviors of TE. When the target furnace temperature was set at 650 C, the specimen with Ti and Al in a 1 : 2 ratio possessed the highest open porosity of 53.89% and the lowest density of 1.58 g cm À3 . When the target furnace temperature was set at 700 C, the specimen with Ti and Al in a 1 : 3 ratio possessed the highest open porosity of 56.27% and the lowest density of 1.44 g cm À3 . The porous specimens with Ti and Al in a 1 : 3 ratio exhibited the best resistance to oxidation at 650 C in air.

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Porous Cu bodies with complex shapes were fabricated by freeze-casting and vacuum sintering water-based CuO slurry. The sintered bodies showed no noticeable macroscopic defects and good shape tolerance. The interconnected pore tunnels were observed by electronic microscopy. The pore size became smaller and the porosity and volume shrinkage of sintered porous bodies decreased with the increase of solid content in the slurry. XRD results showed the CuO was fully decomposed by vacuum sintering into Cu without any second phases. This new fabrication method may be especially economical when small quantities of porous parts are required.