An exploratory investigation on the in-situ synthesis of SiC/AlN/Al composites by spark plasma sintering

The powder mixtures of aluminum and silicon carbonitride (Al-SiCN) have been consolidated into bulk materials by spark plasma sintering. XRD patterns indicated the in-situ formation of SiC and AlN. The density of the SiCN-Al composite sintered by SPS at 500 degrees C is 2.65 g/cm(3) or higher in a weight range of SiCN powder particles up to 2.5%. The formation of new phases and the relatively absence of porosities in the matrix composites are attributed to the co-existence of solid-liquid state that leads to the effective densification of the mixed powders. The breakdown of SiCN network structure was considered to result from a reaction between partially aluminum melt and SiCN particles. An improvement in density and hardness is observed. (C) 2014 Elsevier B.V. All rights reserved.