从逻辑增长模型认识铁磁质的磁化现象  

Understanding the Magnetization Phenomenon of Ferromagnetics Based on Logistic Growth Model

作　　者：赵亮[1] ZHAO Liang(Key Laboratory of Advanced Science and Technology on High Power Microwave,Northwest Institute of Nuclear Technology,Xi’an 710024,China)

机构地区：[1]先进高功率微波技术重点实验室,西北核技术研究所,西安710024

出　　处：《现代应用物理》2024年第6期156-162,共7页Modern Applied Physics

基　　金：科技创新特区基金资助项目(DH863061733)。

摘　　要：逻辑增长模型曲线具有“慢-快-饱和”的“斜S”特点;铁磁质材料的起始磁化曲线也具有这种“斜S”特点。鉴于两者的相似性,本文用逻辑增长模型的理论曲线拟合铁磁质的磁化实验数据,发现两者高度吻合。逻辑增长模型具有正反馈机制,即人口增长率与人口总量近似满足二次函数关系。鉴于此,推测铁磁质材料中的磁筹改变也具有这种正反馈机制,即已翻转的磁筹数n随外加磁场强度H的增加速率与翻转磁筹数n可近似表示为:dn/dH=kn-an^(2),其中,k和a均为常数。从文献中总结的磁化特征,基本证实了上述推断。除此之外,本文还根据逻辑增长模型给出了一种精确的相对磁导率理论公式。The curve of logistic growth model which is used to describe the increase of population has a feature of slow-fast-saturated growth rate.The initial magnetization curve of ferromagnetics in the hysteresis loop also displays such feature.Due to the similarity,the logistic growth model is used to describe the initial magnetization phenomenon of the ferromagnetics.It is found that the curve deduced by the logistic growth model fits well the experimental data obtained in the magnetization processes of two types of ferromagnetics.The logistic growth model has the positive feedback characteristics,i.e.,the increase rate of population is approximately proportional to the total population itself.In view of this,it is conjectured that the increase of the magnetic domain also obeys this characteristics,i.e.,the increase rate of the number of the reversed magnetic domain n to the applied magnetic field H dependent on n itself can be expressed as:d n/d H=kn-an^(2),where k and a are both constants.By summarizing the magnetization characteristics of ferromagnetics in literatures,this conjecture is basically verified.In addition,a precise formula for the relative permeability of the ferromagnetics is proposed based on the logistic growth model.

关 键 词：铁磁质 初始磁化曲线 逻辑增长模型 磁筹 

分 类 号：TM85[电气工程—高电压与绝缘技术] O441[理学—电磁学]