On Creep-Fatigue Interaction During Crack Growth

摘要

The interaction between creep and fatigue processes was investigated during crack gorwth in sheet specimens of the aluminum alloy 5052 at 400F. Fractographic studies indicate that at high frequencies (1/30 sec. per cycle) the fatigue process of crack advance is dominant, whereas at low frequencies (e.g., 60 sec. per cycle) the creep process prevails. It was found that at low frequencies and at a low peak stress level (10 ksi) the cyclic process could lead to an increase in the total time to failure as compared to the creep process alone. (Author)