An investigation of plastic behaviour in cold-rolled aluminium alloy AA2024-T3 using laser speckle imaging sensor

Abstract

The mechanical anisotropy of aluminium alloy AA2024-T3 with strong cold-rolled crystallographic texture is investigated in this paper. A non-contact and non-destructive laser speckle imaging sensor is developed for surface strain measurement so that extensive mechanical tests can be readily performed without surface preparation on the specimens. Both Hill’s 48 and Yld2004-18p yield functions are accurately calibrated using the experimental results from uniaxial tensile, pure shear and plane-strain tensile tests. The constitutive models based on these yield functions were successfully implemented in a commercial finite element (FE) package Abaqus via user material subroutine UMAT. Simulations of single element tensile tests and pure shear tests were carried out to validate the accuracy of UMAT subroutine. The performance of these constitutive models was further evaluated with deep drawing experiments in which the predicted earing profiles were compared with those obtained from FE simulations. The results showed that the constitutive model based on Yld2004-18p yield function accurate representing the anisotropic behaviour of AA2024-T3. The predicted earing profiles coincide well with experimental measurements.