The casting of materials using microwave energy: A review

Knowing the advantages of microwave processing on different materials, it has established a good base for the sintering process. Although it has similar advantages for other processes, still other fields are not much established for industrial use. Microwave casting is one of the emerging fields which are yet to be studied in detail. In this paper, a literature review is carried out for the microwave casting of different materials such as metals, metal matrix composites (MCC), etc. Microwave casting is processed under an apparatus that involves microwave hybrid heating (MHH) where heat is transferred to charge using susceptor material. Further depending upon the designed apparatus, microwave casting is divided as in-situ and ex-situ casting processes. If molten material is allowed to solidify inside the microwave cavity is termed as 'in-situ" casting while if molten material is allowed to solidify outside the microwave cavity it is termed as 'ex-situ" casting. From the review, it can be concluded that the microwave casted materials produce better properties as compared to conventional casting processes in terms of homogeneity and mechanical properties. But most of the research is reported for low melting point materials like Aluminum and their alloys. With the implementation of a new design setup, microwave casting can be used for the materials that are having a melting point above 1000 °C.