Transition metal boride enable applications in fields of cutting tools as the hard phase, but their fabrication suffers from shortcomings in high temperature for binary and hard/soft phase balance. Here, we leveraged a WCoB-Co cermets prepared by using elemental powders of W, Co and B powders via in situ synthesis method and investigated the microstructure evolution of a composite structure of WCoB/Co. The phase evolution, microstructure evolution and mechanical properties were investigated using X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS). The complete sintering process consist of three solid-phase reaction stages and one liquid-phase sintering stage. The solid-phase reaction stage includes the following three reactions: B + 2Co → Co₂B, 11 W +15 Co₂B → 9WCoB + W₂Co₂₁B₆, and 14 W + 2W₂Co₂₁B₆ → 12WCoB + 23Co + Co₇W₆. The eutectic liquid phase, essential for the densification, forms at 1323 °C. The Rockwell hardness and density value reach 87.5HRA and 12.11 g/cm³, respectively. At 1380 °C, the traverse rupture strength (TRS) reaches the peak value of 1495 MPa. Moreover, the results show that transgranular fracture is the main fracture mode. The densification stage was completed at ~1400 °C. In particular, Co₇W₆ phase was discovered during the study of the evolution of WCoB-Co cermets. An increase of the B content was found to be beneficial to eliminate the Co₇W₆ phase that proved to be detrimental to mechanical properties.

过渡金属硼化物可以在切削工具领域中用作硬质相，但由于二元和硬质/软质相平衡的高温，它们的制造存在缺陷。在这里，我们利用原位合成方法，使用W，Co和B粉末的单质粉末制备了WCoB-Co金属陶瓷，并研究了WCoB / Co复合结构的微观结构演变。使用X射线衍射（XRD），差示扫描量热法（DSC），扫描电子显微镜（SEM）和能量分散光谱仪（EDS）研究了相演化，微结构演化和力学性能。完整的烧结过程包括三个固相反应阶段和一个液相烧结阶段。固相反应阶段包括以下三个反应：B + 2Co→Co₂ B，11 W +15 Co ₂ B→9WCoB + W ₂ Co ₂₁ B ₆和14 W + 2W ₂ Co ₂₁ B ₆  →12WCoB + 23Co + Co ₇ W ₆。在致密化过程中，共晶液相在1323°C时形成。洛氏硬度和密度值分别达到87.5HRA和12.11 g / cm ³。在1380°C下，横向断裂强度（TRS）达到1495 MPa的峰值。而且，结果表明，经晶断裂是主要的断裂方式。致密化阶段在〜1400°C下完成。特别是Co ₇ W ₆在研究WCoB-Co金属陶瓷的演化过程中发现了相。发现B含量的增加有利于消除被证明对机械性能有害的Co ₇ W ₆相。