The influence of equi-biaxial and uniaxial tensile pre-strain on the low cycle fatigue performance of the AA2024-T4 aluminium alloy

Abstract

In the present investigation, the low cycle fatigue performance of the aluminium alloy AA2024-T4 is examined for different tensile pre-straining histories. The equi-biaxial tensile pre-strained specimens revealed identical fatigue life to the 0% pre-strained specimens, while all the uniaxial tensile pre-strained specimens showed improved fatigue life. As-received specimens exhibit noticeable cyclic hardening at all the strain amplitude. The pre-strained specimen shows an almost stable cyclic stress–strain response for each strain amplitude. The electron backscattered diffraction examination of the without pre-strained and pre-strained specimens revealed large lattice distortion in the equi-biaxial tensile pre-strained case in comparison with the other two cases.