Improvement of Microstructure and Mechanical Properties of Alumina/Silicon Carbide Nanocomposite via Multi-step Sintering

In current work, the effect of nanosized silicon carbide as reinforcing phase and multi step sintering on flexural strength and Vickers hardness of alumina/silicon carbide nanocomposite was investigated. The results illustrated that in spite of decrease in the densification by addition of SiC, hardness and flexural strength of composite comparing with pure matrix was increased. Also, multi-step sintering to reach the same final temperature results, the increment of the density of composites that leads to enhancement of hardness and strength of composite. Mechanical properties improvement trend had the maximum on the application of reinforcing phase. Hence addition of 5 and 10 weight percent of SiC was the optimum quantity of reinforcing phase in order to achieve the maximum of hardness and flexural strength of composite respectively.