Microwave sintering of nanocrystalline WC–12Co: Challenges and perspectives

Microwave sintering of microcrystalline and nanocrystalline WC–12Co powder compacts was carried out employing different time–temperature schedules. The microcrystalline powder compacts were made from powders with particle sizes ranging from 5 to 45 μm by using methyl cellulose as the lubricant. The nanocrystalline powder compacts were made from powders having a mean WC grain size of 38 nm, without employing any lubricant. The sintered samples were characterized with respect to their densities, Vickers hardness, fracture toughness and microstructures and the challenges encountered during microwave sintering of the WC–12Co powders are discussed.