Abstract

The effects of the hole size(2R) and the specimen width(W) on the fatigue strength and the fatigue life in plain woven glass/epoxy composite plates are experimentally investigated under constant amplitude tensile fatigue loading. It is shown in this study that the notch sensitivity under fatigue loading is lower than that under static loading. It can be explained by the fact that the stress concentration is relaxed by the damage developed at the boundary of circular hole. To predict the fatigue strength at a specific cycle, the modified point stress criterion represented as a function of the geometry of the specimen(2R and W) is applied. It is found that the model used in the prediction of the notched tensile strength predicts the fatigue strength with reasonable accuracy. A model for predicting the fatigue life in the notched specimen, based on the S-$N_f$, curve in the smooth specimen, is suggested.

Keywords

• Circular Hole;
• Notch Sensitivity;
• Fatigue Strength;
• Modified Point Stress Criterion;
• Fatigue Life;
• S-$N_f$ Curve

• 원공;
• 노치민감도;
• 피로강도;
• 수정점 응력조건;
• 피로수명;
• S-$N_f$ 곡선;