Influence of Melting State of Deposited Layer at Electromagnetic Launch Sliding Electrical Contact Interface on Armature Melting

In the repeated launching process, there is an Aluminum Deposited Layer (ADL) on the rail surface. The ADL will melt when heated, and its different melting states will have an important influence on the armature melting process. Therefore, it is necessary to analyze the melting characteristics of the armature under different melting states of the ADL. Firstly, the ADL’s thickness and its melting state are analyzed. Secondly, theoretical calculation models of armature melting are established under the partially melted state and the fully melted state of the ADL, respectively, and the influence of the melting state of the ADL on armature melting is investigated. Finally, considering the effect of non-uniform contact pressure on contact resistance, a three-dimensional finite element simulation model of armature surface melting morphology was established based on multi-physics field coupling for a more accurate analysis of armature surface melting and making a comparative analysis with the experimental results and theoretical analysis results. The results show that the ADL’s thickness increases linearly with the number of shots. When the ADL’s thickness is thin enough, it is in a fully melting state. With the increase in the ADL’s thickness, the ADL will transition to a partially melting state. When the ADL is in a fully melting state, the melting of the armature decreases with the increase in the ADL’s thickness. When the ADL’s thickness reaches a certain value, the corresponding armature melting is reduced to the minimum and no longer changes. The maximum melting depth of the armature surface calculated by finite element is 0.617 mm, which is close to the experimental measurement result of 0.6 mm, verifying the accuracy of the model. The research results can provide a basis for studying the melting mechanism of the armature and provide technical support for controlling ADL and optimizing the design of the armature structure.