Construction And Application Of Prediction Function For Shot Peening Process Of Aluminum Alloy

Due to the influence of the initial stress and the surface stress after processing,the surface deformation of aluminum alloy thin-walled parts will be different,which often fails to meet the requirements of design accuracy.The generation of deformation has become a difficult problem in the manufacturing of aluminum alloy thin-walled parts.In order to weaken or regulate the deformation,the prediction function of peening process-surface characteristic value was constructed according to the distribution characteristics of the surface stress field of the material,which has important reference significance for the accurate control of the surface stress.In this paper,BBD design method was used to obtain the action rules of different shot peening processes on the surface stress and surface hardness of aluminum alloy through experiments.After the correlation analysis of the data,the prediction function of process parameters on the stress and hardness was obtained,and the accuracy of the function was verified.The specific research work is as follows:1.Shot peening experiment designed by BBD method,particle size,air pressure,shot peening time and distance of four factors,shot peening treatment was carried out on the sample,using X-ray stress test surface stress,by microhardness tester and portable roughness measuring instrument for measuring the surface hardness and roughness,state of stress and hardness distribution,explore the component characteristics of stress and hardness distribution,analyses the specimen surface hardness and the stress distribution rule.2.The analysis after the data of shot peening treatment,shot peening process is constructed under the surface stress and hardness prediction function,cause the model prediction model deviation stress test,hardness test error,error of the model error was analyzed,and determine the uncertainty of the error,finally calculate synthetic shot peening process-characteristic value prediction model of total uncertainty.3.On the premise of the expected stress and hardness value,the prediction function can obtain the shot peening process parameter set,so as to compare the experimental and computational results,and finally verify the reliability of the prediction function.For the application method of the prediction function,an expected surface stress of-304 MPa can be given,and 10 sets of process parameters are given by the function.After the expected value of 211 Hv is selected from the corresponding hardness value,the target process parameter set can be determined at last.The prediction function of shot peening process parameter-surface characteristic value can effectively improve the accuracy of surface characteristics obtained under shot peening strengthening,and provide engineering reference for mastering the law of shot peening process for material surface strengthening.