Study on Mechanical Properties and Fracture Mechanisms of B 4 C-CeB 6/A1 Composites

Abstract

B 4C-CeB 6/Al composites were first fabricated by pressureless infiltration technology. The mechanical properties of B 4C-CeB 6/Al composites were tested. The results show that the density, the flexibility strength and the fracture toughness of B 4C-CeB 6/Al composites were greatly improved compared with those of monolithic boron carbide, but the hardness of it decreased. The analysis of B 4C-CeB 6/Al composites by using the fracture scanning electric microscope and the back-scattering equipment showed that, the fracture way of B 4C-CeB 6/Al composites was intercrystalline rupture. The flexibility strength and the fracture toughness of B 4C-CeB 6/Al composites were greatly improved for two major reasons. Firstly the flexibility strength and the fracture toughness of B 4C-CeB 6 porous perform were improved because for the CeB 6 existing. Secondly the ductility of aluminum was manifested in B 4C-CeB 6/Al composites.