Research On Preparation Of Alumina Honeycomb Structure

Nowadays, due to their high specific surface area, high temperature and corrosion resistances, the novel honeycomb ceramic materials have widely applied in common industrial fields such as mechanics, electronic engineering, metallurgy and chemical engineering, as well as advanced national defense technology, especially in aeronautic and astronautic applications.In this paper, the micron honeycomb ceramic structure was produced by the templet in-situ synthesized using the chelation effect of alginate sol with the addition of Cu2+. First, the sodium alginate-alumina stable composite sol was prepared by dispersing the alumina nano-powder into the sodium alginate sol. Then, by adding Cu2+ into the sol, the honeycomb structure, i. e. the micron pore array, was formed as a result of the in-situ chelation effect of alginate sol induced by the appearance of Cu2+. Subsequently, the final honeycomb structure alumina ceramic was produced after following evaporation, ion exchange, drying and sintering procedures. The morphologies of dried gels and sintered samples were observed using SEM, and the elemental distributions were characterized by EDX. The optimized processing parameters were provided based on the experimental results and discussion as well. Finally, the producing mechanism of the micron honeycomb ceramic structure by the in-situ chelation effect of alginate sol with the appearance of Cu2+ was discussed.According to the experimental results, alumina powders were well-dispersed into alginate sol at the pH value of 6. The good alumina honeycomb structure can be obtained at the sodium alignate/alumina mass ratio of 4:1, after the chelation with the CuCl2 solution at Cu2+concentration of 0.007Mol/L, evaporation using acetone, ion...