摘要
针对传统管件电磁胀形存在管件壁厚减薄严重和变形不均匀等问题,提出基于双层凹型集磁器结构的单线圈管件电磁成形方法,通过径向电磁力场分布的调控和轴向电磁力的协同加载,为同时抑制管件壁厚减薄和改善变形均匀性提供了新的技术途径。为验证该方法的有效性,基于电磁-结构场耦合数值模型,对比探究有无双层凹型集磁器下轴径电磁力分布特性、管件壁厚减薄量以及轴向变形均匀性等关键物理量的变化规律,研究集磁器的内凹高度对管件成形行为的影响。仿真结果表明,与传统管件电磁胀形方法相比,新方法下管件壁厚减薄量可从22.07%降低至8.30%,且轴向均匀性扩大至2.31倍。
Electromagnetic forming technology has significant advantages over mechanical processing technology in the processing of light alloy materials and is an important way to realize energy saving and emission reduction in aerospace,automobile manufacturing and other fields.However,the traditional electromagnetic tube expansion process has the defects of serious wall thinning and uneven axial deformation.Based on the traditional electromagnetic tube expansion system,this paper proposed a novel type of double-layer field shaper to regulate the distribution of magnetic field and electromagnetic force.The new field shaper structure can adjust the radial electromagnetic force distribution characteristic from“small at the ends,large in the middle”mode to“large at the ends,small in the middle”mode.And the smaller axial electromagnetic force at the end of the tube can be adjusted to a larger electromagnetic force.The adjustment of the radial electromagnetic force field distribution can weaken the radial electromagnetic force in the middle of the formed tube,thus changing the deformation shape of the tube and improving the characteristics of uneven axial deformation of the tube;the adjustment of the axial electromagnetic force field distribution can promote the flow of the material at the end of the tube to the middle area,compensating for the reduction of the wall thickness of the tube due to radial expansion,thus suppressing the wall thickness thinning phenomenon of the tube.To verify the effectiveness of the double-layer field shaper,the finite element model of electromagnetic coupling structure for the electromagnetic tube expansion system was established by using COMSOL software.In this paper,the change laws of the key physical quantities,such as,the electromagnetic force distribution,the axial deformation uniformity and the wall thickness thinning amount were compared and studied under the condition with or without field shaper.On this basis,the influence of the inner cavity depth of the field shaper on the forming effect of tubes was further explored.The simulation results show that the new field shaper structure improves the axial uniformity by 2.31 times compared with the traditional expansion process, and reduces the wall thickness thinning from 22.07% to 8.30%. The effectiveness of the new field shaper structure in improving the wall thickness thinning and uneven axial deformation of tubes was verified. In addition, increasing the concave height of field shaper is helpful to restrain the wall thinning of tubes, and increase the axial uniformity in a certain range. However, with the further increase of the concave height of field shaper, the radial and axial force fields in the tube forming area are further regulated, the axial uniformity will slightly decrease, but it is still significantly better than the traditional tube expansion effect. It is worth mentioning that the bulging method proposed in this paper adopts single drive coil with simple structure and convenient toolingcompared to multi-coil electromagnetic forming systems. The actual effect of the bulging method will be further verified from the experimental level in the future.
作者
邵子豪
吴伟业
汪晨鑫
邱立
Shao Zihao;Wu Weiye;Wang Chenxin;Qiu Li(College of Electrical Engineering and New Energy China Three Gorges University,Yichang 443002 China;Hubei Provincial Key Laboratory for Operation and Control of Cascaded Hydropower Station,Yichang 443002 China;State Grid Anhui Electric Power Co.Ltd Lai'an County Power Supply Company,Chuzhou 239200 China)
出处
《电工技术学报》
EI
CSCD
北大核心
2024年第5期1245-1255,共11页
Transactions of China Electrotechnical Society
基金
国家自然科学基金资助项目(51877122)。
关键词
电磁成形
电磁力
集磁器
变形行为
Electromagnetic forming
electromagnetic force
magneticfield shaper
deformation behavior
