Research On Laser Shocking Of Thin-walled Titanium Alloy In Strengthening And Deformation

Laser shock processing technology is a new type of material surface strengtheningtechnology, in the aerospace, precision processing and manufacturing, automobile manufacturing,shipbuilding and other fields have broad prospects. Titanium alloys are currently used inaerospace field most of one of the materials, the use of intensive processing of titanium alloymaterial surface strengthening technology of laser shock, improves the mechanical properties oftitanium alloy materials, adapting to the various conditions of service environment. This paperanalyzes the domestic and foreign research on laser shock peening technology, simulationexperiment and finite element numerical, titanium alloy thin-walled parts caused by the residualstress field and plastic to study and predict the deformation strengthening on laser shock, themain research contents and results are as follows:1. Analysis of the basic theory of laser shock processing. The process of laser shockprocessing is: the pulse laser beam impact to the material surface; The generation of laserinduced plasma shock wave; Shock wave loading into the material, produce plastic deformationand a certain depth of residual compressive stress. Pressure wave of the estimates for quantitativesimulation to study the effect of laser shock processing is essential.2. Based on the laser shock wave pressure conversion formula under the constraint model, byusing ABAQUS software as the platform, with dynamic analysis and static mechanics analysis ofthe simulation method of each iteration, successfully completed the finite element simulation oflaser shock processing titanium alloy thin-walled parts, and to deal with the data obtained, lasershock processing parameters are discussed and the influence on the effect of the shock solutionfor material. Combining with the engineering application of laser shock processing, according toactual working condition characteristics, in the process of model of aircraft engine blade hascarried on the finite element simulation of laser shock processing, after the blade impact with aprediction of the residual stress distribution and plastic deformation, the deformation control inengine blade production work provide certain theoretical basis.3. The process of laser shock strengthening is studied experimentally, mainly on the laserpower density and the number of experiments was conducted to study the impact of multiplefactors. X-ray diffraction method was used to test the laser shock after the material surfaceresidual stress. The experimental results show that, laser shock processing TC4titanium alloythin-walled parts can be produced on the surface of large compressive stress, and the material toproduce plastic deformation, so as to prolong the lifetime of the material. The research proved that the residual stress tests on specimens after impact, and the numerical simulation resultscomparing test value, data is close to prove that the numerical simulation method, simulation onlaser shock process is feasible.4. In order to improve the laser shock strengthening caused by the residual stress and theprediction efficiency of plastic deformation, considering the complexity of the finite elementanalysis method, this paper proposes a combination of support vector machine algorithm andparticle swarm optimization (SVM-PSO) based on the calculation of laser shock residual stressand plastic deformation prediction method. The numerical simulation of72groups of sampledata obtained in the process of training, the establishment of laser shock peening residual stressand plastic deformation prediction model. Numerical simulations are performed to verify the36groups of sample data, test results show that the use of SVM-PSO with the algorithm canproduce residual stress and plastic deformation of laser shock strengthening effective prediction.