Development and characterization of SiC fiber reinforced B4C composite

Abstract

This study is conducted to investigate the effects of silicon carbide short fiber (SiCf) reinforcement on processing and properties of boron carbide ceramic. Studies have been carried out on the hot pressing, mechanical property measurement, microstructure evolution and oxidation study of SiCf reinforced B4C composite. B4C-SiCf composites have been prepared by hot pressing at 1950℃ with varying SiCf content in the range of 10 vol% to 30 vol%. All the composites are densified to near theoretical density. It is noticed that hardness of composite is decreased and fracture toughness of composite is increased by addition of SiC fiber. Hardness of the composites are found in the range of 32 GPa to 38 GPa. Fracture toughness of the composites are obtained to be higher than that of the monolithic boron carbide. The values are measured in the range of 4.3 MPa⋅m-½ to 5.1 MPa⋅m-½. In microstructure evolution it is found that SiC fibers are uniformly distributed throughout the matrix. The developed B4C-SiCf composites have been found to have good resistance to oxidation at 800℃ in air.