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Ceria-based Al2O3 composite electrolytes were prepared using (CeO2)0.6(SmO1.5)0.2(GdO1.5)0.2 (C6S2G2) and Al2O3 powders, employing sol-gel and low temperature combustion synthesis methods (SGLCS). The influence of Al2O3 content on the sintering behavior and electrical properties was studied. The results showed that electrical properties could be improved by adding 10wt% Al2O3. The sintered density was up to 5.61g/cm3. Most measurements of open circuit voltage (OCV) ranged between 0.8 and 1.2V; an OCV value of 1.15V was obtained at 370oC. The performance of intermediate- temperature solid oxide fuel cells (ITSOFCs) with a properly Al2O3 doped electrolyte was better than when a pure ceria-based one was used. The highest power density was 200mWcm-2.

The mechanisms of densification during laser ignited reaction sintering of Ni-Al-Cu powder materials were studied. With the addition of Cu, densification of Ni-Al-Cu specimens made of big particles was realized under laser rapid ignition and sintering without signification change of the final products. Filling of the mixture of liquid and disintegrated small grains or particles was regarded as the dominant mechanism for the final densification.

Abstract: TiC/Ni3Al composites have been obtained in situ by laser ignited self-propagating high-temperature synthesis (LISHS) of an intimate mixture of compacted powders of elemental C, Ti, Ni and Al. Ignition temperature (T ig) and combustion temperature (T c) are investigated; the effects of Ni3Al content on density, phase composition, microstructure of the reaction products and particle size of the synthesized TiC were studied. The results show the density of the products varies with Ni3Al content, and a maximum value of density appears at 50wt.% Ni3Al; TiC and Ni3Al are the two stable phases after SHS, TiC particle size decreases with the increasing of Ni3Al content, however, the decreasing of grain size is unobvious when Ni3Al content is over 60wt.%. [Copyright &y& Elsevier]