Crack Growth Under Cyclic Compression

Abstract

An investigation was made of fatigue crack growth in notched samples of 7075-T6 aluminum alloy which were subjected to cyclic compressive loading. Photoelastic techniques were employed to determine plastic strain distribution in the vicinity of the notch at different load levels. A fracture mechanics model relating crack growth to residual tensile stress at the notch root is proposed. Validity of the model is examined by comparing calculated stress intensity values based on the model with stress intensity values determined from the observed growth rate data.