This research paper explores the frequency- and temperature-dependent properties of tape wound magnesil core and air core, which are two feasible options for realizing inductors that can withstand high temperatures. The investigation focuses on understanding how temperature affects the performance of the inductor magnetic materials, with inductance characterization tests conducted at temperatures up to 500℃. To analyze the loss performance of the two cores at a specific operating point, the researchers develop an empirically formulated loss model validated through experimental data collection. The findings indicate that both types of cores exhibit strong resilience to high temperatures, while the system is operating at 200W, 160V to 48V conversion at 100kHz and has been tested up to 250C. The findings report that when the magnesil core is used, the total loss in the system is approximately four times higher compared to using the air core, primarily due to the domination of core losses and reduced inductive properties at higher switching harmonics.