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

• In-situ synthesis of SiC/AlN/Al composites by SPS of powder mixtures of Al and SiCN.
• The formation of new phases and the relatively absence of porosities are attributed to the co-existence of solid–liquid state.
• XRD patterns revealed the in-situ formation of SiC and AlN.
• An improvement in density and hardness is observed.

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°C is 2.65 g/cm3 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.