Microstructure of Nanocrystalline WC Powders and WC-Co Hard Alloys

A set of WC-Co hard alloys was sintered from WC powders with different mean particle sizes. WC powders with particles having different mean size were prepared by high-energy ball milling and by plasma-chemical synthesis. The microstructure and mean grain size of sintered WC-Co hard alloy specimens were studied by means of SEM and XRD. Vickers hardness and microhardness of sintered WC-Co hard alloys were measured. The mechanical strength of rods prepared from different WC-Co hard alloys was examined by bending tests. After the bending tests, the fracture surfaces of all specimens were studied by SEM.