| Résumé | This paper describes an investigation into the fatigue threshold behaviour of two structural aluminium aerospace alloys, Al 2014-T6 and Al 7075-T6, when subjected to Mode II, Mode III and mixed Mode II/III loading. A unique four-point shear loading test rig was employed to cyclically load sharply edge-notched square bar specimens using an increasing load technique. The main aim of the work has been to generate Mode II–Mode III interaction diagrams for the fatigue threshold in each case, in order to facilitate improved design procedures for components fabricated from these alloys, which are susceptible to fatigue cracking under predominantly shear type loading. Aircraft are subjected to structural loads consisting of: pressurization, tension/compression, bending, shear and torsion, both on the ground and in flight. Representative fatigue fracture surfaces have been examined using scanning electron microscopy. |
|---|
