Reactive and non-reactive preparation of B6O materials by FAST/SPS

B6O materials were prepared by a reactive and a non-reactive sintering routine using FAST/SPS and sintering temperatures of 1850 °C. Their sintering behavior, phase and microstructure formation and the mechanical properties are comparatively discussed. We demonstrate that the reactive sintering of B/B2O3-mixtures with oxide sintering additives is a promising and cost-effective alternative to the densification of pre-synthesized B6O with a resulting hardness of up to 22 GPa (HV5) and a fracture toughness of up to 3 MPa m (SEVNB) similar to non-reactive prepared B6O materials. The flexure strength is up to 360 MPa and 540 MPa for the reactive and non-reactive sintered materials, respectively, and substantially affected by the amount of B2O3 in the sintering liquid.