Very high cycle and gigacycle fatigue of fiber-reinforced composites: A review on experimental approaches and fatigue damage mechanisms

A comprehensive review is conducted on the very high cycle (VHC) and gigacycle (GC) fatigue of fiber-reinforced composite materials. The main objective was to conduct a benchmarking survey of high-frequency fatigue test methods that have been introduced by different research groups for testing beyond 107 loading cycles. Therefore, test methods are classified into two major groups, i. e. axial and bending tests. Axial fatigue tests were performed whether by conventional servohydraulic or by ultrasonic testing machines. For bending tests, three approaches have been taken into account. Firstly, conducting cantilever bending fatigue tests using a shaker-based actuator. Secondly, testing by an ultrasonically actuated three-point bending test set-up, and finally, using an electro-dynamically actuated four-point bending test device. The measures that are taken to mitigate challenges of testing at high-frequencies are put forward. The effect of loading frequency and temperature rise on fatigue behavior is investigated. VHC fatigue damage mechanisms are scrutinized for different composite materials, layup configurations, and testing approaches. Considering the importance of modeling in the design stage, the models that have been developed so far for predicting fatigue behavior of composite materials in the VHC and GC fatigue regimes, are presented. Finally, by performing a gap analysis, new perspectives required to be investigated more deeply are nominated.

Automated summary

This comprehensive review focuses on the high cycle and gigacycle fatigue of fiber-reinforced composite materials, categorizing different test methods and fatigue behavior, as well as presenting models for predicting fatigue behavior in VHC and GC regimes. The study also highlights the need for further investigation in certain areas to deepen understanding in the field.