Fatigue Damage and Failure for Notched Plates of Short Glass Fiber Reinforced Polypropylene

摘要

The effect of the fiber length on the fatigue damage initiation was studied on notched plates of short glass fiber reinforced polypropylene subjected to pulsating tension. To evaluate quantitatively the fatigue damage, we measured the luminance distributions by means of the luminance measuring technique using a CCD camera. We observed the notch root surface to reveal the process of crack initiation. The experiment shows that the number of loading cycles required to initiate the fatigue damage was governed predominantly by both the maximum elastic stress at the notch root and the notch-root radius. On the basis of the idea of severity near the notch root, the experimental results of all notched specimens can be explained. Closer observation revealed that the process of initiation and growth of the fatigue damage zone is dependent on the fiber length of FRP plates.