一個多世紀以來，鐵芯一直被用於電感器中，但鐵會導致高頻時的磁損耗增加。要減輕鐵芯相關問題的一個可行方法是使用軟磁材料，如鐵氧體或軟磁複合材料。其他材料，如軟磁複合材料（SMCs），在鐵基粉末上使用無機絕緣塗層，如Al2O3、TiO2和SiO2，來減少渦電流損失也是很好的選擇。在這個研究中，我們旨在利用模擬方法來研究SMC磁芯的磁特性。SMCs的偶極矩、磁各向異性能是由VASP，一個使用ab-initio的軟體來計算的。考慮到顆粒的大小和排列，在固體或黏性介質中構建了一個粒子分散的模型。透過ab-initio計算結果，每個粒子都被分配了一個磁矩和偶極，。SMC磁芯的磁滯環是通過Monte Carlo模擬（透過Metropolis演算法進行）。預測的磁滯環為我們提供了磁性質，如SMC磁芯的飽和磁化強度、殘留磁化量和矯頑磁場。所用的哈密頓方程主要考慮了磁偶極相互作用、外磁耦合和基於固體的矩陣內的磁各向異性能量。模擬結果將有助於開發磁性質更好的理想SMCs。

Iron cores have been used in inductors for over a century, but the iron can result in increased magnetic losses at high frequencies. A feasible approach to mitigating the problems associated with iron cores is the use of soft magnetic materials, such as ferrites or soft magnetic composites. Other materials such as soft magnetic composites (SMCs) that use inorganic insulating coatings such as Al2O3, TiO2, and SiO2 on iron-based powders to reduce eddy current losses are also good alternatives. In this project, we aim to utilize simulation methods to study the magnetic properties of SMC cores. The dipole moment, magnetic anisotropic energy, and exchange energy of the SMCs were calculated by VASP, an ab-initio calculation software. A dispersed particle model was constructed in a solid or viscous medium, considering particle size and arrangements. Each particle is assigned a magnetic moment and dipole, obtained from ab-initio calculations. The hysteresis loop of the SMC cores was evaluated by Monte Carlo simulations with the Metropolis algorithm. The predicted hysteresis loop gives us magnetic properties such as saturation magnetization, remanent magnetization, and coercive field of the SMC cores. The Hamiltonian used primarily considers the magnetic dipole interactions, exchange coupling, and magnetic anisotropic energy within the solid-based matrix. The simulation results would help develop desired SMCs that offer better magnetic properties.

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