Interference Fit Fasteners: a Finite Element Process Modeling Round Robin

Abstract Interference fit fasteners (IFFs) have been widely used in the aircraft industry for several decades and have been shown to provide benefit to fatigue performance. However, the interference and potential plastic deformation near the hole create complications when trying to account for the benefits of IFFs in fatigue predictions. This paper documents new and original results from a recent round robin effort regarding finite element (FE) process modeling of IFFs. Submissions were received from eight participants across seven different organizations and included the use of five different FE software packages. The problem statement involved a 2024-T351 aluminum alloy dogbone sample with a centered hole and a steel IFF with three different levels of interference. In addition to the varying levels of interference, applied remote loading was also considered with three different levels. The round robin included a phased approach with increasing complexity. The results provide useful insight into the stress state near an interference fit hole and represent a comprehensive set of analysis data for use in future validation efforts against measurement data from representative experimental tests.