MICROSTRUCTURE AND DEFORMATION FRACTURE MECHANISM OF WC IN CEMENTED CARBIDES.

Observations by electron diffraction and diffraction contrast on the microstructure and the deformation fracture process of WC in cemented carbides, such as YG8, YG11, YG12 and H//1//2S//2, were carried out with TEM. Results showed that there are varieties of microstructures in WC grains, such as dislocations tangling with high-density, stacking faults, interface dislocations, superdislocations, small-angle grain boundaries and dislocation networks formed by the interaction of dislocations. This paper mainly deals with the microstructure change in WC when the alloys are subjected to stress and strain and fracture are observed. The evidence of transgranular fracture for the alloys is provided, and an explanation is made from the point of view of crystallography.