摘要
High performance SiC-AlN composites were fabricated by hot-pressing with Y2O3 as additive via liquid phase sintering. The SiC-AlN composites containing 5 vol. pet AIN exhibit superior mechanical properties with flexural strength, fracture toughness and Vickers hardness of 1131 MPa, 6.1 MPa.m(1/2) and 28.6 GPa respectively. Microstructure observations indicate that the grain size of the composites is obviously inhibited due to the formation of solid solution. TEM-EDS analysis demonstrates the existence of the solid solution. In addition, subgrain boundaries induced by dislocations in the matrix SiC grains, seem to divide a large grain into numerous nano-sized small grains, which significantly increase the mechanical properties of the composites.
High performance SiC-AlN composites were fabricated by hot-pressing with Y2O3 as additive via liquid phase sintering. The SiC-AlN composites containing 5 vol. pet AIN exhibit superior mechanical properties with flexural strength, fracture toughness and Vickers hardness of 1131 MPa, 6.1 MPa.m(1/2) and 28.6 GPa respectively. Microstructure observations indicate that the grain size of the composites is obviously inhibited due to the formation of solid solution. TEM-EDS analysis demonstrates the existence of the solid solution. In addition, subgrain boundaries induced by dislocations in the matrix SiC grains, seem to divide a large grain into numerous nano-sized small grains, which significantly increase the mechanical properties of the composites.
