Abstract: An electromagnetic-structure-thermal multi-physics coupling model is established to study the melting erosion on the contact interface between U-shaped armature and rails of a multiturn serial-parallel railgun, and the armature velocity, contact pressure and temperature of interface in the case of different current peaks and shrink ranges are analyzed. The related verification experiments were made to obtain the melting erosion characteristic of contact interface. The simulated and experimental results show that the contact pressure between armature and rails varies with current fluctuation during launching. The friction heat power varies directly with the contact pressure, but Joule thermal power caused by contact resistance varies inversely with the contact pressure. The ambient temperature of the sliding contact interface can be further improved by reasonable design of armature shrink range. Due to the inevitable wear during sliding, the melting area of armature contact surface gradually transfers from the initial contact area to the tail of armature. The experimental results validate the effectiveness of the simulation method. Key

Key words: multiturnserial-parallelrailgun, electromagneticlaunching, contactinterface, meltingerosioncharacteristic, contactforce, Jouleheat, frictionheat