Background Electromagnetic rail launchers (EMRLs) have good application prospects in military field due to their ultra-high exit speed, excellent control ability and concealment and low cost advantages. However, under pulsed power excitation, the armature/rail (A/R) interface is under extra conditions, leading to severe ablation on the rail surface.
Purpose This study investigates the arc ablation resistance and underlying mechanisms of various copper-based rail materials, aiming to guide material selection for components susceptible to arc ablation in EMRLs.
Methods By embedding an insulated rail segment at a designated position within the launcher to initiate an arc discharge, arc ablation resistance tests were conducted on different materials. To comparatively analyze the arc ablation resistance of the materials, scanning electron microscopy (SEM) was employed to observe the post-ablation surface micromorphology of H62, Cu-20Ag and Cu-5W.
Results The results indicate that Cu-5W exhibits superior arc ablation resistance compared to the others. After ablation, the Cu-5W rail surface remained relatively smooth, with fewer and smaller pores. In contrast, the ablated H62 surface displayed numerous pores and protrusions, along with a high density of large-scale cracks. Although the Cu-20Ag rail showed relatively few cracks after ablation, it featured a significant number of large-diameter pores.
Conclusions These observations suggest that Cu-5W is a more suitable potential material for arc-ablation-resistant regions of the rail surface in EMRLs.