电工技术学报2024，Vol.39Issue(23)：7309-7318,10.DOI:10.19595/j.cnki.1000-6753.tces.231994
考虑颗粒属性的软磁复合材料磁特性预测方法
Prediction of Magnetic Properties of Soft Magnetic Composites with Considering of Particle Properties
摘要
Abstract
The development of modern electric equipment towards high quality and differentiation has led to an increase in the demand for the uniqueness of physical parameters of electric materials.Soft magnetic composites(SMC)is a novel type of soft magnetic material with isotropic magnetic properties that is prepared by the powder metallurgy process.In comparison to metal soft magnetic alloys,it exhibits higher resistivity and three-dimensional molding capabilities.In contrast to ferrite materials,it has a higher saturation magnetic induction strength.Consequently,SMC offer a unique combination of high flux density and low loss for electrical equipment,a characteristic that is challenging to achieve with soft magnetic alloys and ferrites.At present,the prediction of magnetic properties of SMC prior to fabrication does not take into account the particle properties,preparation process parameters,and microstructural parameters,which results in biased evaluation results.In order to address these issues,a novel method for predicting the magnetic properties of SMC materials combining the discrete element method(DEM)and the finite element method(FEM)is proposed.This method is of great significance in facilitating the accelerated development of SMC and in optimizing the design of the global structure of electrotechnical equipment. A simulation of the preparation of SMC was conducted using DEM.Firstly,the SMC particle properties-including shape,size,and particle size distribution-were analyzed according to scanning electron microscopy.Secondly,the particle properties were simulated using DEM with spherical(single ball),rectangular(two ball stacked fit),and trigonal(three ball stacked fit)shapes.The particle size distributions were homogeneous,isotropic,and normal.Finally,DEM was used to simulate the SMC preparation process,which involved powder filling and pressure pressing. The magnetic properties of SMC were evaluated using FEM.To address the computational challenges associated with the established FE model of micro-scale SMC,a method to construct a homogenized equivalent FE model for SMC is proposed.This method reduces the computational cost while ensuring the accuracy of the magnetic property prediction.The analysis of DEM revealed that the simulated mass density was in close agreement with the actual value when the particle shape was set to be trigonal.Consequently,trigonal particles were retained for use in the FE model to establish the material homogenization equivalent model.Firstly,a cube is established as the solution domain of the FE model.N3 trigonal particles are uniformly and periodically arranged to fill the solution domain,with N representing the number of particles on one side of the trigonal particles.The volume fraction of the particles in the FE model is calculated by using the relative density.The gap between particles is adjusted by the number of particles on one side N,to simulate the actual microstructure of the SMC.Finally,the relative permeability and eddy current loss of SMC were calculated using FEM. The following conclusions are drawn from the combination of experimental preparation measurements and computational simulation calculations: (1)The microstructure of SMC can be approximated when the particles in the DEM use trigonal particles and normal distributions,and the compaction density of the DE model is closest to the measured values. (2)In the prediction of magnetic properties,the homogenized equivalent FE model is effective in making predictions of relative permeability and eddy current loss.A more accurate prediction can be achieved by using trigonal particles and a number of particles on one side of N=40,taking into account the computational accuracy and the cost of FEM computation. The DEM-FEM regulation mechanism of SMC was proposed,but the skin effect at high frequency and the process of heat treatment have not yet been considered.Further research will be conducted to address these issues.关键词
软磁复合材料/颗粒属性/离散元/磁特性Key words
Soft magnetic composites/particle properties/discrete element method/magnetic properties分类
信息技术与安全科学引用本文复制引用
赵轩哲,张殿海,史凯萌,任自艳,张艳丽..考虑颗粒属性的软磁复合材料磁特性预测方法[J].电工技术学报,2024,39(23):7309-7318,10.基金项目
国家自然科学基金(51707125)和辽宁省教育厅科学研究项目(LJKZ0125)资助. （51707125）
