Fatigue crack propagation of new aluminum lithium alloy bonded with titanium alloy strap

A new type of aluminum lithium alloy (Al–Li alloy) Al–Li–S–4 was investigated by test in this paper. Alloy plate of 400 mm × 140 mm × 6 mm with single edge notch was made into samples bonded with Ti–6Al–4V alloy (Ti alloy) strap by FM 94 film adhesive after the surface was treated. Fatigue crack growth of samples was investigated under cyclic loading with stress ratio (R) of 0.1 and load amplitude constant. The results show that Al–Li alloy plate bonded with Ti alloy strap could retard fatigue crack propagation. Retardation effect is related with width and thickness of strap. Flaws have an observable effect on crack propagation direction.