Magnetic Simulation of Iron-based Structural Material with Lattice Defects

Abstract

Micromagnetic simulations using the Landau-Lifshitz-Gilbert (LLG) equation were performed to clarify the effect of voids caused by lattice defects in iron-based structural materials on their magnetization processes. We analyzed the magnetization process of magnetic clusters with voids by applying an external magnetic field. Compared to void-free cases, notable differences were observed in the magnetic hysteresis curves, domain wall displacement (DWD), and variations in exchange and magnetic dipole energies. In particular, the pinning phenomenon, in which the domain wall stretches slightly and DWD is prevented around the voids, was observed, and this is thought to be due to a decrease in the exchange energy as the magnetic wall passes through the voids. Furthermore, as a result of changing the position and size of the voids, it was found the timing and amount of the energy change varied.