Microstructural investigation of variable tungsten reinforcement in copper-based composite microwave castings

The composite castings of Cu-xW (where; x=5, 10, and 15 wt.%) have been successfully developed by a novel processing route. The concept of microwave hybrid heating is successfully applied in this study and cast samples were developed in a domestic microwave oven with a maximum power of 900 W and at a frequency of 2.45 GHz. The in situ melting and cast samples were developed with in a duration of 07 min of microwave radiation exposure. The microstructure of cast samples developed shows a regular, roughly hexagonal grain growth that resembles cellular proliferation. The recrystallization and grain growth suppression after adding W content in Cu have been revealed. The formation of different phases such as Cu₆₄O and CuWO₄ were observed. The Vicker’s microhardness value of composite cast samples was observed to increase more than twice of pure copper cast samples.