Effects Of Laser Induced Cavitation Impact On Tensile Properties And Stress Corrosion Resistance Of 5A03 Aluminum Alloy

Laser induced cavitation impact is a surface modification method,belonging to the typical interdisciplinary research content.Impact dynamics,hydrodynamics and materials science are its most critical basis subjects.In this paper,the related mechanism and experimental study on the tensile and stress corrosion resistance of marine 5A03 aluminum alloy subjected to laser impact induced cavitation impact were studied.The main work includes:(1)On the basis of summarizing the research on the surface deformation strengthening,the improvement of anti-stress corrosion resistance of aluminum alloy and laser induced cavitation,the paper deeply analyzes the laser induced cavitation impact mechanism and the stress corrosion of aluminum alloy.The effects of laser shock induced cavitation and high temperature retention on the tensile and stress corrosion resistance of aluminum alloys were discussed.Theoretical can provide support for the follow-up experimental research.(2)Laser-induced cavitation impact treatment and the following heat treatment in200 ? and 300 ? for different length of time were carried out.The surface of the sample after the different process was tested,including hardness,residual stress,and micro-structure state.It was found that the surface hardness of the 5A03-H112 aluminum alloy was improved after laser induced cavitation impact.Besides,the surface grain refined,the precipitation phase increased,the dislocation density increased,and the residual compressive stress was generated.After HT of 200 ?,the residual stress has a small degree of relaxation and the hardness is also slightly reduced,dislocation density decreased but the aluminum alloy surface grain is more uniform and clear,precipitation phase distribution is more dense and dispersion.After the insulation at 300 ?,due to the material recrystallization,grain grew up,dislocation density decreased,the residual stress significantly relaxation and hardness decreased significantly.(3)Tensile test at room temperature and stress corrosion corrosion test in NaCl solution:The samples of 5A03 aluminum alloy after different processes were subjected to room temperature tensile test,and the slow tensile test was carried out in 3.5% NaCl solution in order to investigate several properties.It was found that laser-induced cavitation impact treatment followed by appropriate HT can increase the strength,plasticity and stress corrosion resistance of marine 5A03-H112 aluminum alloy,especially the stress intensity and stress corrosion resistance coefficient under stress corrosion environment.The results show that the strength and plasticity of the 5A03-H112 aluminum alloy are improved by the laser induced cavitation impact,and the fracture strength in the stress corrosion environment is also greatly improved,and the stress corrosion susceptibility coefficient is obviously decreased.The HT at 200 ? can enhance the effect of deformation strengthening treatment.However,after the HT at 300 ?,the material is softened,the strength is greatly reduced,the stress corrosion resistance is weakened,and the strengthening effect is basically gone.In addition,this paper analyzes and summarizes the mechanism of improving the stress corrosion resistance of aluminum alloy by the process of deformation strengthening and heat treatment.The research results of this paper can provide reference for the production practice and the concrete engineering application of 5A03 aluminum alloy.