Finite-Element Analysis Of The Rail-Type Electromagnetic Launcher’s Gouging Behavior

The phenomenon of gouging on the surface of the rail for the course of launching of the rail-type electromagnetic launcher will affect the accuracy and efficiency of the launch. It’s a significant obstacle to its repeating and practical use. Over the years, many countries have carried out their experiments, but that takes so much time and money. In recent yrars, the softwares for the simulation have becomed more and more perfect, so it becomes necessary to research the theory and simulation first to reduce the workload and cost.Firstly, according to the characteristics and the reason for gouging, proposed a dynamical model of oblique impacting of small angle. Deducing the physical expression of collision-related and the relationship between the parameters of material and critical time for instability phenomenon based on the basic theory.Then, using AISI4340 steel as the model material and make the instability phase diagram to describe the instability phenomenon under plane strain condition. It shows that the local buckling shear is more difficult to happen compared with the loading condition of pure shear by one-dimensional. And the gouging phenomenon will be significantly inhibited with the increase of the characteristics of rail’s material, such as the work hardening coefficient, thermal softening coefficient, work hardening stress and strain rate sensitivity.Finally, the numerical simulation has been carried out with the finite element software LS-DYNA under the variable parameters. The process and factors on the depth of gouge were analyzed. The result shows that the depth of the gouge will decrease with the enlargement of it’s front end chamfering radius, it’s width and the radiuses of curvature do not exactly match. And the impact of these factors is not linear. The new formation mechanism and numerical method provide a new effective way for the anti-gouging research.