Effect Of Shot Peening And Vibration Stress Relief On A6N01S-T5 Aluminum Alloy

The A6N01S-T5 aluminum alloy is a common material used in modern high speed train body,and it has important practical significance to improve the fatigue strength of A6N01S-T5 aluminum alloy.Shot peening technology is one of the most effective surface engineering technology to improve the fatigue strength of the material.It has been widely used in the fields of aerospace,high-speed railway,automobile and so on.But the parts are often influenced by working environment in practical use,especially the vibration.This will lead the stress relaxation of the parts to influence the effect of shot peening,so it is very necessary to study the effect of vibration on shot peening strengthening.In this paper,the influence of different shot peening parameters and vibration on the shot peening effect of A6N01S-T5 aluminum alloy was studied,based on the method of numerical simulation and experiment.First,use the APDL language in ANSYS/LS-DYNA to establish a multi shots random distribution model.Based on this model,the influence of the shot speed,shot diameters and the coverage rate on the residual stress distribution and the surface roughness of the shot peening were simulated.The simulation results show that when the coverage rate reaches a certain value,the residual stress distribution will tend to be stable,surface roughness of the part is saturated.The larger the shot speed,the deeper of the residual pressure layer is,the larger the surface roughness is.Therefore,the shot peening effect is not increased with the increase of the shot speed.There is an optimal velocity value.The influence of shot diameter on the residual stress distribution is greater,and the shot diameter plays a decisive role in the depth of the residual compressive stress layer.The experiment of shot peening for A6N01S-T5 aluminum alloy was did.The surface roughness and fatigue life were obtained at different shot peening pressure and coverage rate by using 3D profiler and fatigue testing machine.And a better of shot peening parameter was obtained.The test results showed that with the increase of pressure,the surface roughness was more and more big,the fatigue life increased first and then decreased;with the increase of coverage rate,the surface roughness increased first and then decreased slightly and the fatigue life increased gradually and reached a steady state finally.In order to study the effect of vibration on the shot peening,the samples treated with shot peening will be put on the electromagnetic vibration table to be vibrated in different vibration amplitude and frequency.Then the fatigue life will be tested and the conclusion will be drawn compared with the fatigue life of the sample before vibration.The results show that the vibration can weaken the effect of shot peening,and the fatigue life of the specimen after shot peening is reduced.