Reliability Fatigue Life and A New S–N Curve Model of Composite Laminates Under Tensile-Tensile Fatigue Load

Tension-tension fatigue experiments on composite laminates were performed under various fatigue stress levels. Static and fatigue failure modes of specimens were analyzed and compared. S–N curves of fatigue life data were built using exponent function. Fatigue life distribution was described by two different distributions, logarithm-normal and two parameters Weibull distribution. Then fatigue life under various probability of survival was calculated and R-S–N curves were built, which indicated the high probability of survival lead to smaller reliability fatigue life. Finally, a new S–N curve model was proposed, which exhibited good accuracy with experimental results.