Multi-physics simulation to estimate exposure time for microwave-assisted metallic cast
Microwave casting utilizes microwave energy to heat and cast metallic materials. This technique is novel and efficient in comparison to traditional methods. This technique has been applied to cast various metallic materials. There are some factors like dielectric characteristics of processing material, casting setup design, and choices of susceptor and mold, that affect the microwave heating rate. Consequently, determining the optimal exposure time for cast experimentally can be challenging. To address this, simulation studies are valuable. This study involves finite element modeling of microwave casting experimental setup. Using finite element simulations, the exposure times are predicted that are required to cast various metallic powders (Ni, stainless steel SS-316, and Cu) under identical parametric conditions in an electromagnetic environment. The impacts of microwave heating are analyzed through electric field configuration, resistive losses, and thermal distribution within the applicator cavity. The electric field intensity is observed to be maximum (4.46×104 V/m) in the susceptor zone, resulting in the highest resistive losses (4.9×109 W/m3) in that area. Under the specified conditions, the exposure times to cast Ni, SS-316 and Cu powder into dimensions of 150×35×3 mm3, are predicted as 2280, 2080, and 1125 s respectively. Experimental results confirm these times with an average percentage error of 13.83%, demonstrating a close correlation between predicted and actual exposure times.