Study About The Cushioning Properties Of The Thin-walled Metal Tube Which Working In High-speed Impact Environment

The working equipment or structural components can be easily damaged and lose the ability to work in the high-speed impact or explosion environment.In order to keep the components work normally in the impact environment,some energy absorption devices are designed to protect the working structure.The thin-walled metal tube which is usually used as plastically deformed buffer has potential application prospects in impact dynamics field because many advantages such as the simple structure, reliable-operation and small load fluctuation.The buffer characteristics of the thin-walled metal tube in the high-speed impact environment is studied by the ways of theoretical analysis, numerical simulation and experimental research in this paper.The structure of traditional metal tube is designed optimized according to its buffer characteristics.Some basic research about the application of the thin-walled metal tube by reducing the load of the on-board structure is taken at the end of this paper.The fundamental research of the thin-walled metal tube which is about the buffer characteristics in high-speed impact environment can be helpful and provide some references to its application in the field of impact dynamics.Established the theoretical model of the thin-walled metal tube's damping force which is impact in high-speed environment by using the method of principal stress and consider the basis of the strain rate effect and inertial effects.The theoretical model mainly describes the sizing section's damping force of the thin-walled metal tube which is impact in high-speed environment.The theoretical model can provide a theoretical basis for the application of the metal tube structure which is working in the high-speed impact environment.The buffer characteristics of the thin-walled metal tube which is working in high-speed impact environment were studied by using an air gun test system where obtained the buffer forcecurves of the thin-walled metal tube.The deformation characteristics and the mechanical characteristics of the thin-walled metal tube which is impacted in high-speed environment is analyzed by the buffer force curve.There are some different between the basic forms and the specific values of the thin-walled metal tube's buffer force curve which is impact in high-speed environment and the buffer force curve which is working in quasi-static environment.The buffer force of the thin-walled metal tube which is impact in high-speed environment is bigger at the beginning stage and the stable buffer stage.The buffer force from the calculated result of the theoretical model the test result was subjected to a comparative analysis.The result of the theoretical model and the experimental data are in good agreement.The theoretical model has a accuracy result and can provide a reference for the computing of the structural applications.Took the numerical simulation of the air gun experiment by using LS-DYNA software and analysed the cushioning effect that from the numerical simulation and the experiment.The numerical simulation and the experimental results are in good agreement and the numerical simulation and the experimental result of the thin-walled metal tube's buffer force is in good accuracy.Analysed the deformation of the thin-walled metal tube in the whole process and the buffer force caused by the deformation at each stage by numerical simulation.Studied the cushioning properties of the thin-walled metal tube that is affected by the impact velocity, the difference of the semi-cone angle and the impact quality.The results of the buffer force characteristics and trends that are affected by the above parameters were obtained by the study,and the results can provide some reference and guidance for the application design of the thin-walled metal tube which is worked in high-speed impact environment.The buffer force characteristics of the thin-walled metal tubes that made of 5A02 aluminum and45 steel is studied comparatively.The total energy absorption capacity and the units quality energy absorption capability of 45 steel thin-walled metal tube are better than 5A02 aluminum and the energy absorption efficiency of 45 steel thin-walled metal tube is better than 5A02 aluminum.According to the buffer force characteristics of the original thin-walled metal tubestructure worked in impact environment,three optimized structure was proposed to improve the energy absorption efficiency.The structure four has the best buffer force characteristics after the comparison of the original structure and the optimized structure about the stable buffer force,the energy absorption efficiency and the energy absorption capability.Finally,the efficiency of reducing the overload of the thin-walled metal tube is studied.The on-board structure can be effectively protect by the thin-walled metal tube composite structure within its working time and the on-board structure's high overload can be reduced when penetrating.Studied the effectively penetrate deep that effected by the thin-walled metal tube composite structure from three aspects including the different length,the different axial length and the penetration speed by numerical simulation.The thin-walled metal tube composite structure which is designed to reduce the on-board structure's overload is suitable to use in short time penetration and small depth penetration.