Surface-engineered tetracosane polymer boost gap conductivity and ablation resistance in Cu-based electrodes

During electromagnetic rail launching, transition-induced damage between the armature and the track inevitably degrades performance. To elucidate the ablation mechanisms of alkane-polymer-coated electrodes under arc discharge, this study combines experiments investigations with finite element and molecular dynamics simulations. Pulsed-gap discharge tests demonstrate that the tetracosane polymer coating undergoes pyrolysis and ionization, releasing charged species that sustain arc combustion, prolong arc lifetime, suppress current chopping, reduce gap resistance, and enhance conductivity, thereby improving electrode anti-ablation capability. Simulation results indicate that the coating effectively lowers peak electrode surface temperatures in the arc zone, while multistep dehydrogenation yields highly unsaturated alkynes. Compared with bare Cu, the polymer layer dissipates part of the incident ion energy, lowering bombardment depth and suppressing backscattering of Cu atoms. These findings offer valuable guidance for the design of high-performance, anti-ablation materials for extreme environments.