火炮电涡流制退机用钕铁硼的热退磁特性  

Thermal Demagnetization Characteristics of Nd-Fe-B Used in Eddy Current Recoil Mechanism of Artillery

作　　者：孙正平[1] 杨国来[1] 李雷 王丽群[1] SUN Zhengping;YANG Guolai;LI Lei;WANG Liqun(School of Mechanical Engineering,Nanjing University of Science and Technology,Nanjing 210094,Jiangsu,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：《兵工学报》2024年第8期2712-2727,共16页Acta Armamentarii

基　　金：国家博士后创新人才支持计划项目(BX2021126);国家自然科学基金青年基金项目(52305155)。

摘　　要：永磁式电涡流制退机是火炮后坐阻力高效控制领域中一种具有创新性的设计,在耗能密度大、工作环境相对密闭的火炮应用场景下电涡流制退机会出现严重的温升现象,高温会导致钕铁硼材料磁性能的下降继而影响制退特性,现阶段钕铁硼的热退磁过程尚不明晰且缺乏理论表达。为掌握钕铁硼热退磁特性,基于微磁模拟方法,从微观磁矩受热运动的角度定量分析不同温度下钕铁硼的退磁过程,得到宏观钕铁硼的退磁曲线。为使退磁曲线更好地指导工程设计,使用J-A模型对钕铁硼退磁行为进行理论描述,并进行实验验证。分别基于传统的剩余磁通密度模型和J-A模型开展钕铁硼退磁与阻力退化的磁热耦合数值计算,通过与原理样机试验结果进行对比发现,J-A模型对钕铁硼磁性能的描述更为准确。计算不同工作温度及膛压下制退机工作性能,分析温度场下钕铁硼退磁特性及制退机阻尼特性。研究结果表明,最恶劣工况下钕铁硼最大退磁量为0.351 T,制退机最大后坐位移为1108 mm,这为电涡流制退机的设计提供了理论参考。Permanent magnet eddy current recoil brake is an innovative design in the field of efficient control of recoil resistance of artillery.In the application scenario of artillery with high energy consumption density and relatively closed working environment,there is a serious temperature rise in the eddy current recoil brake.High temperature will lead to the decrease in the magnetic properties of Nd-Fe-B materials and then affect the recoil characteristics.At present,the thermal demagnetization process of Nd-Fe-B is not clear and lacks theoretical expression.In order to grasp the thermal demagnetization characteristics of Nd-Fe-B,the demagnetization process of NdFeB at different temperatures is quantitatively analyzed from the perspective of microscopic magnetic moment heating motionbased on the micromagnetic simulation method,and the demagnetization curve of macroscopic Nd-Fe-B is obtained.In order to use the demagnetization curve for better guiding the engineering design,the J-A model is used to describe the demagnetization behavior of Nd-Fe-B,and the experimental verification is carried out.The magneto-thermal coupling numerical calculation of demagnetization and resistance degradation of Nd-Fe-B is carried out based on the traditional residual magnetic flux density model and the J-A model.By comparing with the experimental results of the prototype,it is found that the J-A model is more accurate in describing the magnetic properties of Nd-Fe-B.The working performance of recoil brake under different working temperatures and chamber pressures is calculated,and the demagnetization characteristics of Nd-Fe-B and the damping characteristics of recoil brake under the temperature field are analyzed.The results show that the maximum demagnetization of Nd-Fe-B is 0.351 T under the worst working conditions,and the maximum recoil displacement of recoil brake is 1108 mm,which provides a theoretical reference for the design of eddy current recoil brake.

关 键 词：火炮电涡流制退机 钕铁硼 微磁理论 退磁特性 

分 类 号：TJ301[兵器科学与技术—火炮、自动武器与弹药工程]