Ultrahard WB₄-B and WB₄-TaB₂ based materials have been obtained by applying glass encapsulated HIPing to mixtures comprised of WB₄ and free boron with and without metallic tantalum additions. Porosity removal is more efficient in the alloy containing metallic tantalum, achieving near full density at temperatures 300 °C lower than those reported so far for these materials. The WB₄ phase is better stabilished by HIPing at 1350 °C than at 1100 °C. This is due to the formation of TaB₂, which, at 1100 °C, likely occurs by direct reaction between metallic Ta and the surrounding WB₄ particles. At 1350 °C, diffusion is enhanced and the reaction between free B and Ta particles becomes more probable. The hardness of hipped specimens ranges from 43 GPa to 24 GPa depending on the applied load. K_1c values calculated from indentation cracks reach 5.6 MPa.m^1/2, assuming Palmqvist type crack shape.

超硬 WB ₄ -B 和 WB ₄ -TaB ₂基材料是通过将玻璃封装的 HIPing 应用于由 WB ₄和游离硼组成的混合物，添加和不添加金属钽。在含金属钽的合金中，孔隙去除更有效，在温度低于这些材料迄今为止报道的温度 300°C 时达到接近全密度。WB ₄相通过 HIPing 在 1350 °C 比在 1100 °C 更稳定。这是由于 TaB ₂的形成，在 1100 °C 时，可能通过金属 Ta 与周围的 WB _{4之间的直接反应发生}粒子。在 1350 °C 时，扩散增强，游离 B 和 Ta 粒子之间的反应变得更有可能。臀部试样的硬度范围为 43 GPa 至 24 GPa，具体取决于施加的载荷。假设Palmqvist型裂纹形状，由压痕裂纹计算的K _1c值达到5.6 MPa.m ^{1/2 。}