Print version ISSN 0366-6913
GARCIA, G. C. R. and RIBEIRO, S.. Study of the viability to produce SiC ceramics by Y2O3-AlN, Y2O3-Al2O3, R2O3-AlN spontaneous infiltration. Cerâmica [online]. 2008, vol.54, n.330, pp. 227-232. ISSN 0366-6913. http://dx.doi.org/10.1590/S0366-69132008000200013.
Silicon carbide ceramics, SiC, obtained by liquid infiltration have shown excellent properties. In infiltration process the contact time of the liquid with SiC at elevated temperature is short, decreasing the probability to form gaseous products that contribute negatively in the final product properties. This phenomenon occurs during SiC liquid phase sintering. The purpose of the present study was to investigate the correlation between wettability and infiltration tendency of some additives in SiC compacts. SiC compacts were prepared by cold isostatic pressing followed by solid phase pre-sintering. Into the compacts were introduced Y2O3-AlN, Y2O3-Al2O3, R2O3-AlN liquids with eutectic compositions at a temperature 10 ºC higher than the melting point of each mixture for 4, 8 and 12 min. Before infiltration, the samples were analyzed by determining densities, crystalline phases, and degree of infiltration. The better results were presented by sample with infiltration with the Y2O3-AlN mixture.
Keywords : SiC; infiltration; wettability.