Grain size effects on notch sensitivity

This work presents experimental results on the fatigue behavior of cracks growing from circular notches under axial loading conditions for a very wide range of notch size to grain size ratios, including cases where the notch size is of the order of, or even smaller, than the grain size. Notch sensitivity is evaluated and the well-known dependence on grain size is clearly demonstrated. It was found that for the same specimen geometry and loading conditions, the influence of the stress concentration is directly dependent on the relationship between the notch size and the grain size.