Trans Tech Publications, Materials Science Forum, (775-776), p. 529-533, 2014
DOI: 10.4028/www.scientific.net/msf.775-776.529
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Porous glass-ceramics belonging to the Li 2 O-ZrO 2 -SiO 2 -Al 2 O 3 (LZSA) system were prepared by gelcasting. This processing technique associated to aeration of ceramic suspensions containing a foaming agent, allows the production of ceramics with high opened porosity (>90%), cell geometry tending to the spherical form, cellular interconnectivity and high green strength. In this work glass-ceramics foams were prepared by addition of different concentrations of foaming agents (Alkolan) and sintered at 750, 850 and 950ºC for 30 min. The LZSA glass-ceramic foams were characterized by density, porosity, thermal shrinkage, microstructural analysis and mechanical strength. The morphological, physical and mechanical properties of the consolidated glass-ceramic foams indicated that the process of gelcasting may be a valid alternative to produce porous materials for applications at temperatures lower than 950°C. Introduction Porous ceramics generally exhibit low density, low thermal conductivity, high surface area, high permeability and chemical resistance. These features allow applications such as filters for high temperature insulation, supports for catalysts, bone implants, among others. [1,2] Thus, in order to obtain ceramics with geometry and final characteristics suited to technological applications, various ceramic processing techniques have been studied. [3,4] Among these, the formation of a gel in situ through the polymerization of organic precursors