Fatigue crack growth in the aluminium alloy D16 under constant and variable amplitude loading

Fatigue crack growth experiments were carried out on sheet specimens of the Russian alloy D16Cz (Al-Cu-Mg alloy). Constant-amplitude tests were performed at different stress ratios. Variable-amplitude tests included experiments with a single overload, periodic overloads and underloads, and the flight-simulation load history miniFALSTAFF. Fractographic observations were made to obtain information from striations and the development of shear lips. Results are presented and compared to literature data for 2024-T3. Attention is paid to incompatible crack front orientations and consequences for crack growth prediction models.