Tough ceramics by microwave sintering of nanocrystalline titanium diboride ceramics

Dense composites of TiB2 with additions of TiN have been produced by microwave sintering. Microwave sintering was conducted at 1200–1700 °C under controlled atmosphere. The effects of composition, sintering temperature, on densification, microstructure, and mechanical properties were investigated. Microwave sintering resulted in uniform crack-free uniform microstructure, as well as maximum relative density of 99% and bending strength of 368±15 MPa, Young's modulus of 440±11 GPa, electric resistivity of 2×10−5 Ω cm, Vickers hardness of 26.2 ±0.4 GPa, and a fracture toughness of 6.2±0.34 MPa·m1/2 were obtained using 36 wt% TiB2, and sintering for 10 min at 1650 °C.