Effect of TiO2 nanoparticles on the pressureless sintering of B4C–TiB2 nanocomposites

• So far, the effect of Titanium Dioxide on properties of Boron Carbide had not been investigated at nano scale by PLS.
• The relative density, micro-hardness and the fracture toughness of Boron Carbide were improved by adding the TiO2.
• By adding 20 wt.% TiO2 nanoparticles at 2175 °C, a relative density of 98% is obtained for the composite.

In this paper, the effect of TiO2 nanoparticles on the sintering ability and physical and mechanical properties of B4C has been investigated. To make the B4C–TiO2 composite, different amounts of TiO2 nanoparticles (5–20 wt.%) were added to Boron Carbide. The samples were sintered at temperatures of 2050 and 2175 °C using the pressureless sintering method. Density, micro-hardness and fracture toughness measuring tests were performed to obtain the physical and mechanical properties of the samples. Also, the microstructures of the samples were examined under the Scanning Electron Microscope. The relative density, micro-hardness and the fracture toughness of Boron Carbide were improved by adding the TiO2. The obtained results indicate that by adding 20 wt.% TiO2 nanoparticles at 2175 °C, a relative density of 98%, hardness of 29.6 GPa and a fracture toughness of 3.51 MPa·m1/2 are obtained for the composite.