Eutectic Al2O3-GdAlO3 composite consolidated by combined rapid quenching and spark plasma sintering technique

A mixture of Al2O3 and GdAlO3 was melted and rapid quenched to produce an amorphous film. Dense eutectic composites were consolidated from ground amorphous powder using both conventional and spark plasma sintering (SPS). Conventional sintering at temperatures above 1600degreesC for 24 h was required for complete sintering. However, using SPS complete sintering could be obtained at temperatures between 1300 and 1500degreesC with no soaking. The SPS technique could consolidate ultrafine eutectic structure from rapid quenched amorphous material, whilst conventional sintering was not successful owing to grain growth. A combination of rapid quenching and SPS resulted in an ultrafine eutectic Al2O3-GdAlO3 structure.