Microstructure and mechanical properties of B4C-NbB2-SiC ternary eutectic composites by a crucible-free zone melting method

Abstract Directionally solidified B4C–NbB2-SiC ternary composites were prepared by a floating zone method based on crucible-free melting of compacted powders. The eutectic composition B4C–15NbB2–35SiC (mol.%) was characterized boron carbide matrix, directionally reinforced lamella-type NbB2 and SiC phases. inclusions about 1−2 μm in thickness uniformly dispersed B4C matrix B4C–NbB2–SiC composite. Vickers hardness indentation fracture toughness the 35.8 GPa 6.4 MPa m1/2, respectively.