A research on WC-8Co preparation by microwave sintering

The microwave sintering technique has been used in WC-Co alloy preparation for many years. The properties of the alloy can be improved using the microwave method even in a very short processing cycle. In this work, the influencing factors of the heating rate on WC-8Co hard metal during the microwave processing were discussed by using a multi-mode high temperature furnace. The experimental results demonstrate that the assisted materials principally contribute to heat insulation, rather than heating. Our results show that, when the temperature exceeds 1100 degrees C, the heating rate of Co compact slows down and displays slight fluctuations. Porosity of the compacts is shown to have little effect on the heating rate. Further, the special microstructure (overall even and local uneven) of the microwave-prepared WC-8Co alloy is discussed. Besides, the relationships between the microstructure and the mechanical properties of microwave-prepared WC-8Co are explored. (C) 2012 Elsevier Ltd. All rights reserved.