Failure Mechanism and Bearing Fatigue of Composite Mechanical Connections with High Lock and Blind Bolted Fasteners

Abstract

In this paper, the bearing fatigue and failure of composite mechanical connections with two types of fasteners were compared and analyzed by fatigue tests. Failure mechanism of composite connections was explored from microcosmic and macroscopic aspects. From macroscopic point of view, the variation rule of hole-deformation with the increase of fatigue times was determined. Two failure modes, fretting wear and impact damage, were observed from the microscopic pictures, which combined to explain the failure mechanism of composite mechanical connections. In the end, the mechanism of interference-fit lengthening fatigue life was explored, which could be used to provide theoretical basis and experimental basis for the subsequent structural design and engineering application.