Construction Of Predictive Function Of Stress-Deformation Of Aerospace Al Alloy Thin-Walled Component

Under the stress distribution,thin-walled Al alloy component will be deformed to varying degrees after forming,which often fail to meet precision requirements of design.This has become a difficult problem to hinder the development of aircraft manufacturing industry.In order to predict deformation effectively,it is very important to predict distribution of thin-walled component based on the stress distribution prediction function.In this paper,the stress distribution of 7075-T651 Al alloy thin-walled component after milling and shot peening was measured.Then stress-distortion prediction function was built through mechanical analysis for Al alloy thin-walled component and the predictability of function was verified and assessed.The specific study works were as follows:1.The milled Al alloy thin-walled component was processed by shot peening.The whole stress distribution state of the component was measured by removal layer method and layer by layer corrosion XRD stress measurement.Then the stress distribution characteristics of the component was explored.2.Combining the dimensional characteristics of Al alloy thin-walled component and using bending mechanics theory,the deformation of component under the overall stress distribution was analyzed mechanically,and the stress-distortion prediction function was established.Under the guidance of the predictive function,a suitable shot peening process is used to effectively adjust deformation of the component,which is of great significance for reducing the processing deformation of the aeronautical thin-walled component.3.The dimensional errors in milling,stress measurement errors,material elastic modulus errors,deformation measurement errors,and theoretical model errors were analyzed to determine the deviation of the prediction model,and uncertainty of each error was determined,and total uncertainty of predictive function of stress-deformation of Al alloy thin-walled component was finally calculated and synthesized.The result shows that the deviation between the calculated value and experimental value satisfies uncertainty requirement.