Toughened silicon carbide and method for making the same

1/2 Pressureless sintering of silicon carbide with fracture toughness in excess of about 4 MPa-mas measured by the single-edge precracked beam (SEPB) technique while maintaining a density greater than 3.1 g/cc for compositions with SiC greater than about 94 wt. % is made possible through the use of metallic Al to promote sintering and grain growth. Boron and carbon may be used as traditional sintering aids, with nitrogen to suppress grain growth, and additions of yttrium and/or lanthanide elements to promote intergranular fracture.