Fatigue behaviour of BS 2L65 aluminium alloy pin-loaded lugs with interference-fit bushes

Abstract

Cumulative fatigue damage has been studied in lugs with and without interference-fit bushes. Fatigue tests have been carried out under constant and variable amplitude loading conditions and local stress measurements have been made using the Companion Specimen Method. Local stress measurements did not explain the large increase in life under constant amplitude loading associated with fitting an interference-fit bush in a pin-jointed lug, nor did they explain the reduction in life following a prestress on such a specimen. However, the stress measurements in sequences representing narrow band random loading were broadly consistent with actual fatigue test results, and enabled more accurate life estimations to be made at the lower mean stress tested, but at a high mean stress the measurements produced unsafe life estimates.