The effect of ZrC on the mechanical response of ZrB₂ ceramics has been evaluated from room temperature to 2000 °C. Zirconium diboride ceramics containing 10 vol% ZrC had higher strengths at all temperatures compared to previous reports for nominally pure ZrB₂. The addition of ZrC also increased fracture toughness from $\sim 3\text{.5}\text{MPa}\sqrt{\text{m}}$ for nominally pure ZrB₂ to $\sim 4\text{.3}\text{MPa}\sqrt{\text{m}}$ due to residual thermal stresses. The toughness was comparable with ZrB₂ up to 1600 °C, but increased to $4\text{.6}\text{MPa}\sqrt{\text{m}}$ at 1800 °C and 2000 °C. The increased toughness above 1600 °C was attributed to plasticity in the ZrC at elevated temperatures. Electron back-scattered diffraction analysis showed strong orientation of the ZrC grains along the [001] direction in the tensile region of specimens tested at 2000 °C, a phenomenon that has not been observed previously for fast fracture (crosshead displacement rate = 4.0 mm min⁻¹) in four point bending. It is believed that microstructural changes and plasticity at elevated temperature were the mechanisms behind the ultrafast reorientation of ZrC.

从室温到2000°C，已经评估了ZrC对ZrB ₂陶瓷机械响应的影响。与先前报道的标称纯ZrB ₂相比，含10vol％ZrC的二硼化锆陶瓷在所有温度下均具有更高的强度。ZrC的添加还增加了断裂韧性$〜3\text{.5}\text{兆帕}\sqrt{\text{米}}$对于名义上纯的ZrB ₂至$〜4\text{.3}\text{兆帕}\sqrt{\text{米}}$由于残留的热应力。在高达1600°C的温度下，韧性与ZrB ₂相当，但增加到$4\text{.6}\text{兆帕}\sqrt{\text{米}}$在1800°C和2000°C下。高于1600°C的韧性增加是由于ZrC在高温下具有可塑性。电子背散射衍射分析表明，在2000°C下测试的试样的拉伸区域中，ZrC晶粒沿[001]方向具有强取向，这是以前从未观察到的快速断裂现象（十字头位移速率= 4.0 mm min）^-1）四点弯曲。据信，高温下的微观结构变化和可塑性是ZrC超快速重新定向的机制。