Formation of a Spherical Structure on the Surface of the 79WC–15TiC–6Co Cemented Carbide upon Interaction with a TiC–20Ni Powder Mixture

The surface structure of a cutting insert of the standard (Ti,W)C–WC–6Co cemented carbide, T15K6, has been studied after interaction with a TiC–Ni based powder mixture. It has been shown that an external layer with two-phase (Ті,W)С–(Co,Ni) and intermediate (Ti,W)C–WC–6(Co,Ni) structures of variable composition is formed on the surface of this insert. The formation of the (Ti, W)С–(Co, Ni) structure in the external layer occurs as a result of Co, W, and C diffusion from the volume of an insert onto its surface and counter Ni diffusion from the surface of an insert into its volume.