Distribution of residual stress in an asymmetric T-section beam by stretch-bending

Abstract

Residual stress is frequently induced during quenching of aluminium alloys, and even following stress relief, it can cause distortions in the subsequent manufacturing processes. Evaluating the spatial distribution of residual stress in safety-critical aeronautical structures is of practical importance. For this purpose, the residual stress distribution of a 2026-T3511 aluminium alloy asymmetric T-section beam under displacement-controlled stretch-bending is investigated. A two-step numerical simulation is performed to predict the residual stress superposition in the quenching and subsequent mechanical processes. Moreover, a multiple-cut contour method is used to measure the stress variations on three distinct cutting planes. The results reveal that bending merely alters the distribution pattern of the residual stress rather than reducing the magnitude, whereas stretch-bending offers the advantages of shape forming and stress relief, which are validated by fabricating a long, asymmetric T-section beam.