Induction heating is a technology that uses heat generated by resistance when a high-frequency current is applied to a coil. An electric range using this is called an Induction Heating (IH) electric range. IH electric ranges are being widely applied in commercial products recently because they have higher thermal efficiency performances than other methods. The performance of a heating coil of an IH electric range greatly varies depending on the shape and number of coils. Thus, research on optimal coil shape and number according to product shape is required. Therefore, this study aimed to design an optimal heating coil at the set temperature of an electric range product. Target temperature was set to the temperature that a commercial stainless-steel container could withstand. The thickness of the coil copper wire, the number of windings, the applied voltage, and the frequency were set as design variables. A sensitivity analysis was performed to check the influence of each design variable on coil temperature. Based on this, optimal design was performed using the response surface method. Electromagnetic field-thermal analysis was performed with the designed coil and a very approximate result was obtained with a 0.07% error from the set target temperature.

Hastelloy-X material is widely used in aircraft engines, furnaces, and chemical process components due to its excellent oxidation resistance and high-temperature strength. In the case of making plate-shaped parts, its quality can be improved by forming limit diagram (FLD), which can predict crack and failure of a product. However, experimental-based FLD can be costly and time-consuming. In this paper, we tried to predict the formability of Hastelloy-X through FE simulations using the GTN (Gurson-Tvergaard- Needleman) model. First, appropriate values for GTN model parameters were derived from RSM using tensile test. FLD based on GTN model was then obtained by applying derived parameters to FLD simulations. These obtained parameters can be used to predict the formability of sheet metal undergoing severe deformation processes in aircraft and gas turbine engine manufacturing.