Transition of W^sub 2^C to WC during carburization of tungsten metal powder

The properties of cemented carbides are heavily influenced by the tungsten carbide (WC) powders used in its production. Overall particle size of the WC is most influential, however, in the medium- and coarse-grained tungsten carbide particle range the internal crystallographic structure of the polycrystalline WC is important as well. To investigate the crystal formation of WC and it's resulting structure, selected crystal growth experiments were performed. The transition of ditungsten carbide (W2C) into tungsten carbide (WC) during carburization of tungsten powder was studied. The experimental strategy was to obtain W2C along with WC within the growing carbide particles. Electron microscopy methods were utilized to study the growth mechanism during conversion of W2C into WC, and to detect the existence of preferred crystallographic orientations during the transition process.