A multi-physics simulation framework for optimizing microwave hybrid heating of metallic powders in a household microwave oven

Abstract Microwave hybrid heating (MHH), which combines microwave irradiation with conductive heating from a susceptor, provides an efficient and energy-saving approach for metal melting. In this study, microwave-assisted melting and casting of metallic powders (aluminium, copper and nickel) was carried out in a 900 W, 2.45 GHz household microwave oven using a graphite crucible and activated charcoal as hybrid susceptors. A comprehensive multi-physics simulation framework was developed to model and optimize the MHH process of metallic powder within the standard microwave oven. This framework integrates electromagnetic field distribution, heating losses, and thermal profiling to capture the complex interactions between microwaves, susceptors, and metallic powder during heating. A simulation study was conducted to predict the exposure time required for efficient melting, providing valuable insights for process optimization. The simulation model showed a close correlation with the experimental results, with an average percentage error of 7.71% in predicting exposure time for different metallic materials across different crucible geometries. Additionally, the simulated thermal profile of the susceptor domain was compared with experimental observations to evaluate model accuracy and reliability. By enabling process optimization prior to physical experiments, the simulation saves time and resources, reduces energy consumption and material waste, and supports the goals of Industry 4.0 for sustainable and efficient manufacturing.