Abstract：The electromagnetic rail launch process exists in high current, ultra-high speed, high temperature-rise, strong friction, and extreme impact conditions. The high heat generated causes the surface of the aluminum armature to melt, resulting in a transition at the pivot-rail interface from solid-solid electrical contact to a solid-liquid-solid melt process. Eventually, molten aluminum solidifies on the rail surface, forming a complex deposition layer. This deposition layer has implications for the performance of the pivot rail system during subsequent launches. The operational environment characterized by ultra-high-speed friction during repeated launches results in a low melting point in the armature. A portion of molten material forms a liquid transferred onto the rail, enhancing the interface and diminishing the electromagnetic rail's longevity. Consequently, it is imperative to investigate the impact of the aluminum deposition layer on the sliding electrical contact at the pivot-rail interface. This study conducted small-diameter electromagnetic launching tests with varying launching times to examine the carrier friction wear behavior of the friction sub-material of the pivot rail. The results revealed that a significant amount of molten aluminum was transferred to the rail surface after multiple launches, increasing the roughness of the pivot-rail interface due to the residual deposit layer. As a result, the pivot-rail friction sub-contact deteriorated, characterized by organizational features such as gouges and cracks on the rail surface. The wear intensity escalated with an increase in the number of launches. However, after a certain number of launches, the aluminum alloy oxide layer on the rail surface reached a critical thickness, reducing the wear on the rail body. Nonetheless, mechanical and electrical wear simultaneously intensified the environmental conditions at the pivot-rail contact surface. Finally, a liquid film fusion deposition model at the pivot-rail interface was developed, and the deposited layer’s impacts on the operational dynamics of the liquid film and the electrical contact condition of the pivot-rail interface were studied. The study involved the calculation of the thickness of the deposited layer and the deposition efficiency for varying launch times. During high-speed launches, the aluminum liquid layer experienced significant viscous forces, and pronounced velocity variations of the liquefied layer at the armature tail exit increased viscous dissipation forces. With multiple launches, heightened interfacial friction can counteract the viscous forces within the aluminum liquid layer, destabilizing the interfacial liquid film. Thickening the aluminum deposition layer on the rail surface can exert extrusion effects on the liquid film, introducing destabilizing factors to the flow of the liquefied layer. Consequently, the aluminum liquid layer, which serves as a lubricant between the armature and the rail, may be extruded from the interface. Therefore, the armature’s normal operation is compromised, and the rail's longevity is diminished.
邢泽西, 王健, 李鸿剑, 韩智云, 李庆民. 重复发射下铝沉积层对枢轨界面滑动电接触的影响[J]. 电工技术学报, 2025, 40(10): 3044-3055.
Xing Zexi, Wang Jian, Li Hongjian, Han Zhiyun, Li Qingmin. Influence of Aluminum Deposition Layers on Sliding Electrical Contact at the Pivot-Rail Interface under Repetitive Emission. Transactions of China Electrotechnical Society, 2025, 40(10): 3044-3055.
[1] 马伟明, 鲁军勇. 电磁发射技术的研究现状与挑战[J]. 电工技术学报, 2023, 38(15): 3943-3959. Ma Weiming, Lu Junyong.Research progress and challenges of electromagnetic launch technology[J]. Transactions of China Electrotechnical Society, 2023, 38(15): 3943-3959. [2] 马伟明. 关于电工学科前沿技术发展的若干思考[J]. 电工技术学报, 2021, 36(22): 4627-4636. Ma Weiming.Thoughts on the development of frontier technology in electrical engineering[J]. Transactions of China Electrotechnical Society, 2021, 36(22): 4627-4636. [3] 翟小飞, 李鑫航, 刘华, 等. 电磁轨道发射系统电路模型及发射效率研究[J]. 电工技术学报, 2023, 38(11): 2841-2849, 2860. Zhai Xiaofei, Li Xinhang, Liu Hua, et al.Research on circuit model and launch efficiency of electro- magnetic rail launch system[J]. Transactions of China Electrotechnical Society, 2023, 38(11): 2841-2849, 2860. [4] Barber J P, Bauer D P, Jamison K, et al.A survey of armature transition mechanisms[J]. IEEE Transa- ctions on Magnetics, 2003, 39(1): 47-51. [5] 胡鑫凯, 鲁军勇, 李白, 等. 瞬态条件下电磁轨道发射装置绝缘体热损伤分析[J]. 电工技术学报, 2023, 38(21): 5673-5681. Hu Xinkai, Lu Junyong, Li Bai, et al.Thermal damage analysis of insulator in electromagnetic rail launcher under transient conditions[J]. Transactions of China Electrotechnical Society, 2023, 38(21): 5673-5681. [6] Stefani F, Levinson S, Satapathy S, et al.Electro- dynamic transition in solid armature railguns[J]. IEEE Transactions on Magnetics, 2001, 37(1): 101-105. [7] Barber J P, Challita A, Maas B, et al.Contact transition in metal armatures (railguns)[J]. IEEE Transactions on Magnetics, 1991, 27(1): 228-232. [8] 黄伟, 杨黎明, 史戈宁, 等. 电磁发射条件下CuCrZr合金材料轨道损伤行为研究[J]. 兵工学报, 2020, 41(5): 858-864. Huang Wei, Yang Liming, Shi Gening, et al.Damage behavior of CuCrZr alloy rail during electromagnetic launching[J]. Acta Armamentarii, 2020, 41(5): 858-864. [9] 李郁兴, 姚萍屏, 李专, 等. 电磁发射CuCrZr轨道的沉积层特征与磨损机理[J]. 粉末冶金材料科学与工程, 2022, 27(4): 409-418. Li Yuxing, Yao Pingping, Li Zhuan, et al.Deposition characteristics and wear mechanism of CuCrZr electromagnetic launch rail[J]. Materials Science and Engineering of Powder Metallurgy, 2022, 27(4): 409-418. [10] Lin Yan, Li Jiazhen, Pan Jie, et al.Current-carrying wear behavior and the interface evolution of the Cu/ Al tribological pair[J]. Engineering Failure Analysis, 2023, 153: 107549. [11] 康丽, 姚萍屏, 王兴, 等. 电磁轨道炮轨道表面熔凝沉积层研究进展[J]. 中国表面工程, 2023, 36(3): 40-51. Kang Li, Yao Pingping, Wang Xing, et al.Research progress in fused deposits on electromagnetic railgun surfaces[J]. China Surface Engineering, 2023, 36(3): 40-51. [12] Wang Zhiheng, Wan Min, Li Xiaojiang.Numerical modeling of electromagnetic railgun rail temperature field[J]. International Journal of Applied Electro- magnetics and Mechanics, 2016, 51(2): 173-183. [13] 韩云天. 电磁发射装置轨道磨损时空分布研究[D]. 秦皇岛: 燕山大学, 2022. Han Yuntian.Study on temporal and spatial dis- tribution of rail wear of electromagnetic launcher[D]. Qinhuangdao: Yanshan University, 2022. [14] Merrill R, Stefani F.A turbulent melt-lubrication model of surface wear in railgun armatures[J]. IEEE Transactions on Magnetics, 2005, 41(1): 414-419. [15] 李白, 鲁军勇, 谭赛, 等. 高速滑动电接触电枢表面动态磨损过程研究[J]. 电工技术学报, 2023, 38(1): 131-139. Li Bai, Lu Junyong, Tan Sai, et al.Research on dynamic wear process of armature surface in high- speed sliding electric contact[J]. Transactions of China Electrotechnical Society, 2023, 38(1): 131-139. [16] 邹昕阳, 陈立学, 王增基, 等. 滑动电接触梯度功能材料电枢熔化磨损特性仿真研究[J]. 电工技术学报, 2024, 39(19): 5947-5957. Zou Xinyang, Chen Lixue, Wang Zengji, et al.Study on melting and wear characteristics of sliding electric contact functionally gradient material armature[J]. Transactions of China Electrotechnical Society, 2024, 39(19): 5947-5957. [17] Greenwood J A, Tripp J H.The contact of two nominally flat rough surfaces[J]. Proceedings of the Institution of Mechanical Engineers, 1970, 185(1): 625-633. [18] Patir N, Cheng H S.Application of average flow model to lubrication between rough sliding sur- faces[J]. Journal of Lubrication Technology, 1979, 101(2): 220-229. [19] Wang Lei.Modeling of the armature-rail interface in an electromagnetic launcher with lubricant inje- ction[D]. Atlanta: Georgia Institute of Technology, 2008. [20] 张益男. 电磁发射轨道的内力及变形分析[D]. 秦皇岛: 燕山大学, 2010. Zhang Yinan.Internal force and deformation analysis of electromagnetic launch orbit[D]. Qinhuangdao: Yanshan University, 2010. [21] 陈克应. 高强接触异质颗粒摩擦界面弹流润滑及结构优化研究[D]. 武汉: 武汉科技大学, 2020. Chen Keying.Study on EHL and structure optimization of friction interface of heterogeneous particles with high strength contact[D]. Wuhan: Wuhan University of Science and Technology, 2020. [22] Balic E E.Melt wear control of metals in high-speed sliding contacts[D]. New York: Rensselaer Polyte- chnic Institute Troy, 2008. [23] Dutta I, Delaney L, Cleveland B, et al.Electric- current-induced liquid Al deposition, reaction, and flow on Cu rails at rail-armature contacts in rail- guns[J]. IEEE Transactions on Magnetics, 2009, 45(1): 272-277. [24] Persad C, Castro Z.Railgun tribology: characterization and control of multishot wear debris[J]. IEEE Transactions on Magnetics, 2007, 43(1): 173-177. [25] Meger R A, Cooper K, Jones H, et al.Analysis of rail surfaces from a multishot railgun[J]. IEEE Transa- ctions on Magnetics, 2005, 41(1): 211-213.
2025, Vol. 40 
