A generalized multiphysics model using COMSOL Multiphysics software for optimizing the sintering process of iron powders having various green densities is developed. The modeling is facilitated by designing a 30 GHz multimode applicator, where the test sample is placed for the microwave processing. The effective dielectric and magnetic properties of the resultant metal powder compact is estimated using the effective electromagnetic model considering the idea of core - shell particle approach followed by the Lichtenecker's mixture formula. A theoretical approach relating the penetration depth, proper impedance matching and volume fraction of different density powder compacts is also discussed here. From the study, it is clear that the effective dielectric, magnetic, and thermal properties all contribute to the microwave sintering process of metal powders.
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