Very High Cycle Fatigue - Testing Methods

Abstract

This paper presents several approaches for investigating the Very High Cycle Fatigue (VHCF) range of composite materials. Starting from the special challenges associated with high frequency testing of composite specimens, the paper shows some solutions as well as results for such investigations. The test set-up used in the research of the authors is a four point bending rig, which allows for relatively high load frequencies and widely avoids overheating. These bending tests provide fatigue limits for the development of microcracking, while showing no specific fatigue damage phenomena in the very high cycle fatigue range. The approaches found both, in literature and at the actual method utilised here, are discussed. The paper relates to glass fibre reinforced plastics (GFRP), and does not include either simulation approaches or results.