Microwave material processing for green technology

Microwave material processing is attracting interest as a green technology for conserving energy and improving efficiency in conventional industrial processes for mitigating CO2 emissions. Because of various advantages over conventional methods, such as rapid and selective heating, as well its ability to provide internal heating of substances, microwave heating can reduce the time and lower the temperature necessary for material processing. Recently, several approaches have been studied for microwave material processing such as the sintering of ceramics, metal powder, and the metal production. Furthermore, thermal non-equilibrium state during microwave processing has been often reported such as enhancement of chemical reactions as well as rapid phase mixing at grain boundary of iron. We have also observed a unique feature of luminescence from several metal oxides such as TiO2 and ZnO during microwave irradiation under vacuum. In this study, wide potential of microwave material processing is proposed for achieving a green technological innovation.