MEASUREMENT OF RESIDUAL STRESSES IN ALUMINIUM ALLOY AEROSPACE COMPONENTS

摘要

The deep hole drilling technique for residual stress measurement is introduced as a practical and versatile technique for measuring through thickness residual stress distributions in aluminium alloy aerospace components. Details and recent developments of the technique are presented and then deep hole drilling is used to determine the through thickness residual stresses in a stepped aluminium alloy, A17XXX, plate originating from the wing skin of a modem civilian aircraft. In addition to deep hole drilling (DHD), conventional incremental centre hole drilling (ICHD) is also applied at the same surface location in order to provide the detailed near-surface residual stresses, and neutron diffraction is used to validate measurements. The results presented demonstrate that DHD and ICHD work well together to provide both near-surface and through thickness residual stress distributions. The results are in reasonable agreement with the neutron diffraction results which assumed a constant stress-free lattice parameter value. The methodologies and techniques described in this paper will be used in the forthcoming EU-FP 6 project 'COMPACT - A concurrent approach to manufacturing induced part distortion in aerospace components' as part of a suite of complementary residual stress measurement techniques.