Microstructure and mechanical properties of TiB2-B4C ceramics fabricated by hot-pressing

In this study, TiB2-B4C composite ceramics were prepared using Y2O3 and Al2O3 as the sintering aids. Different contents of B4C were added to seek promoted comprehensive mechanical properties of the composites. The mixed powders were sintered at 1850 degrees C under a uniaxial loading of 30 MPa for 2 h via hot-pressing. Through the measurement of XRD, SEM and related mechanical properties, the influence of B4C content on the microstructure and mechanical properties of TiB2-B4C composites ceramics was discussed. The experimental results show that TiB2-B4C composite ceramics exhibit excellent mechanical properties, which can be attributed to the dense microstructure and fine grain size. In addition, TiB2-B4C composite ceramic shows a relatively high comprehensive properties when the addition amount of B4C is 20 wt%. The relative density, Vickers hardness, fracture toughness and flexural strength are measured to be 99.61%, 27.63 +/- 1.73 GPa, 4.77 +/- 0.06 MPa m1/2, 612.5 +/- 28.78 MPa, respectively.