NDT of Residual Stress in Thick Aluminum Alloy Plates under Different Aging Conditions Using Multiple Techniques

In this paper, a portable residual stress tester and synchrotron radiation diffraction technique were used to measure the residual stress distribution of thick 2A14 aluminum alloy plates under different aging conditions after solution treatment. The stress changes after solution and aging were analyzed using metallographic structure observation, electron backscattered diffraction (EBSD), X-ray diffraction (XRD), and other characterization methods. The results show that after solution treatment at 500 °C and aging at 170 °C, the second phase precipitates, lattice distortion is released, and the stress level gradually decreases with aging time. The residual stress of the plate comprises compressive stress; there is stress concentration in the central area. The stress distribution obtained by the two residual stress calculation methods, cosα and sin²ψ, under different process conditions was consistent.