Finite Element Simulation of Residual Stress around Split Sleeve Cold Expanded Hole for AA7075

Abstract

Split sleeve hole cold extrusion strengthening technology is one of the most commonly used fatigue resistance technology for metal structures. The residual stress field of the hole cold extrusion strengthening structure needs to be analysed, which is an important part of the fatigue life study. Finite element analysis for the 7075 aluminum alloy cold extrusion strengthening plate is carried out in this paper. The effects of split sleeve and reaming process are considered in the analysis process, and the residual stress field at the hole edge is obtained. The numerical results are verified by the experimental results, which show that the two are in good agreement. It is show that the residual stress is the compressive stress near the extrusion hole while the tensile stress far away from the extrusion hole. Additionally, the compressive stress value is the largest in the middle layer, the smallest in the squeeze layer, and the value in the extrude layer is between the two.