Low-cycle fatigue anisotropy and fracture behavior of the die-forged
2014 aircraft wheel
Abstract
In order to provide a sufficient theoretical basis for the fatigue
resistant design of the aircraft wheels, strain-controlled low-cycle
fatigue (LCF) tests were carried out on specimens machined in the
extrusion direction (ED) and transverse direction (TD) of die-forged
2014 aluminum alloy wheel. Although the TD specimens show lower tensile
strength and yield strength, the fatigue test results reveal that the TD
specimens show superior fatigue life compared with the ED specimens at
total strain amplitudes of 0.5% ~ 0.8%. This is
predominantly caused by the Al 12(MnSi)
2(FeCu) intermetallic particles near the surface layer
lead to a relatively short crack initiation stage for the ED specimens.
In contrast, TD specimens with finer and more uniform recrystallized
grains have better resistance to fatigue crack initiation (FCI) and
propagation (FCP).