电涡流制退机用烧结钕铁硼去磁行为的实验研究与数值模拟  

Experimental Study and Numerical Simulation of DemagnetizationBehavior of Sintered NdFeB Used in Eddy Current Brake

作　　者：李超[1] 杨国来[1] 李雷 LI Chao;YANG Guolai;LI lei(School of Mechanical Engineering,Nanjing University of Science and Technology,Nanjing 210094,China)

机构地区：[1]南京理工大学机械工程学院,江苏南京210094

出　　处：《弹道学报》2023年第2期53-59,共7页Journal of Ballistics

基　　金：国家自然科学基金项目(52105106)。

摘　　要：针对传统火炮上液压制退机存在的漏液、难以维修等问题,利用电磁阻尼机理的电涡流制退机应运而生。烧结钕铁硼作为其中关键的功能件,在火炮发射环境下的磁场保持问题备受关注。为探究此问题,设计了冲击去磁实验平台,测量了不同冲击速度下的冲击载荷与磁体产生的感应电动势,获得了磁体的磁通量变化曲线。结合实验数据特点,建立了烧结钕铁硼的冲击去磁理论模型,开发了冲击去磁过程的联合仿真模型方法,并通过与实验值对比的方法验证了冲击去磁理论模型的有效性。建立了火炮发射非线性动力学模型,结合建立的冲击去磁模型对火炮后坐运动中电涡流阻尼器的去磁效应进行了研究。结果表明,最右端烧结钕铁硼永磁体整体处于可逆去磁区域,仅在永磁体内圈产生不可逆去磁现象,去磁量为0.275 T。该去磁模型拓展了烧结钕铁硼的材料属性,电涡流制退机中去磁效应的仿真计算结果为烧结钕铁硼在电涡流制退机上的工程化应用提供了理论依据与参考。Aiming at the problems of liquid leakage and difficult maintenance of hydraulic brake on traditional artillery,the eddy current brake using electromagnetic damping theory emerges as the times require.Sintered NdFeB is the key functional part of eddy current brake,and its magnetic field retention problem in the artillery launch environment has attracted much attention.To study this issue,a shock loading demagnetization experiment-platform was established,and the shock demagnetization experiments were conducted.The impact load and induced electromotive force of the magnet at different speeds were measured,and the magnetic flux curve of the magnet was obtained.Combined with the characteristics of experimental data,a theoretical model of shock loading demagnetization of sintered NdFeB was established.The co-simulation model of the shock demagnetization process was established.The validity of the theoretical model of shock demagnetization was verified by comparing with the experimental values.The non-linear dynamic model of the artillery launch was established.Combined with the established shock demagnetization model,the demagnetization effect of the eddy current brake of the artillery was studied.The results show that,the rightmost sintered NdFeB permanent magnet is in the reversible demagnetization region,and an irreversible demagnetization phenomenon occurs in the inner ring of the permanent magnet,and the demagnetization amount is 0.275 T.The material properties of sintered NdFeB are expanded.The simulation of the demagnetization effect in the eddy current brake provides the theoretical basis and reference for the engineering of sintered NdFeB in the eddy current brake.

关 键 词：电涡流制退机 烧结钕铁硼 冲击去磁 去磁模型 仿真计算 

分 类 号：TJ303.4[兵器科学与技术—火炮、自动武器与弹药工程]