Influence of stress ratio on fatigue crack propagation in TiAl alloy

摘要

Based on the experiments did by B. K. Parida and T. Nicholas, the fatigue crack propagation rate of TiAl alloy under different stress ratios had been tested in order to find out the role of stress ratio and to derive an improved fatigue crack propagation formula for region Ⅱ(the expansion region) according to Paris formula and to calculate the specific values of the constants in the formula. The experimental results reveal that stress ratio has a significant influence on fatigue crack growth rate.