The effect of polyacrylamide on the soft magnetic properties and temperature rise characteristics of FeSiBNbCu nanocrystalline soft magnetic composites

In this study, a novel and efficient polyacrylamide insulation coating is chemically prepared on the surface of FeSiBNbCu powder, and the effect of acrylamide content on the soft magnetic properties of the corresponding nanocrystalline soft magnetic powder cores (NPCs) was investigated. At 1.5 wt% of acrylamide, the NPCs shown lowest P cv of 725.16 mW/cm3 at high frequency (20 mT, 2 MHz), mechanical properties and the direct current (DC) bias performance was significantly improved. Furthermore, the electromagnetic heat generated by the NPCs was simulated using Comsol Multiphysics, and an electromagnetic-thermal coupling model is proposed to simulate the inductive temperature rise. The results demonstrated that the magnetic density and loss maps of the core were significantly reduced after coating, resulting in a maximum temperature reduction of approximately 31 K. These findings suggest that reducing magnetic loss at high frequencies can reduce the temperature rise of the core by preparing a homogeneous and stable polyacrylamide coating with excellent performance on the surface of the magnetic powder.