Fatigue Life Simulation and Experiment of 2024 Aluminum Joints with Multi-Fasteners Interference-Fit

A three-dimensional finite element model of 2024 aluminum hi-bolted joint was established. Hi-bolts installation and pre-tightening force applied were simulated, then distal alternating load on middle plate of the joint. Fatigue life was predicted with FE-SAFE soft, and verified by experiment. The simulation results show that middle plate is the weakest plate in the plates of the joint. Hoop residual compressive stress increases with raising interference, and decreases gradually from the hole to the outer edge. Fatigue life is longer with interference fit than clearance, and it is benefit for fatigue life improvement with interference from 0.08 to 0.14 mm. While fatigue test results show that failure origins from No. 2 hole of the middle plate. The fatigue life grow longer with interference from 0 to 0.11 mm, then shorten with 0.14 mm interference. The fatigue life is longest with 0.11 mm interference. The suggested interference for engineering is 0.08–0.11 mm for possible defects with 0.14 mm interference.