用透射电子显微镜对YG8、YG11、YG12和H_(12)S_2等几种硬质合金中WC的微观结构和形变断裂过程进行了观察、电子衍射和衍衬分析。结果表明,合金中WC晶粒内部有着非常丰富的微观结构,例如,高密度的位错纠缠、堆垛层错、界面位错、超位错、小角度晶界,以及由位错交互作用形成的位错网络等。本文着重探讨了,当合金承受应力,产生应变和断裂时,WC晶内微观结构变化规律,这为合金穿晶断裂提供了实验依据,并试图从晶体学的角度给予解释。 The microstructures and deformations and fracture processes of WC in several cemented carbides, such as YG8, YG11, YG12 and H12S_2, were observed by transmission electron microscopy, electron diffraction and diffraction analysis. The results show that there are abundant microstructures in the WC grains, such as high-density dislocation entanglement, stacking faults, interfacial dislocations, super-dislocations, small-angle grain boundaries, and dislocation interactions Dislocation network and so on. This article focuses on the microstructure variation of WC crystal when the alloy is subjected to stress, strain and fracture, which provides an experimental basis for the transgranular fracture of the alloy and tries to explain it from the perspective of crystallography.