The effect of contact pad geometry on fretting fatigue behavior of high strength steel was examined by using the clamping double bridge pads system. In order to investigate the effects of bridge pad shapes, the fretting fatigue tests were carried out by using four types of bridge pad with different leg height h*. The fretting fatigue strength decreased with decreasing in the h*. Also, the stick area increased as increasing of the h*. The contact pressure distribution was measured by strain gauge and calculated by using a finite element method in order to investigate the effect of the pads leg height h*. The contact pressure concentrated in the inside on the contact surface where the main crack initiated. Two-stage tests were carried out in order to investigate the fretting fatigue damage. The two-stage test was performed to a certain cycles under fretting condition and then plain tests without fretting as removing the pads were continued.
In structures having stress concentration under cyclic loading, a small crack initiates and it grows and propagates. The present paper shows the experimental results of the perforated plate having the different diameters and the prescribed different strain amplitude. In the specimens having a circular hole, a crack initiates at the hole side having the most severe stress concentration in the specimen, and then the other crack also starts to initiate at the opposite hole side. Growth of both cracks is observed from the photographs taken at each cycle to study the relation between crack growth and load decrease. The feature of crack growth initiating from multiple origins will be discussed for fatigue test. The crack initiation is evaluated by referring to the accumulation law using the simplified estimation scheme, and the crack growth is evaluated by referring the increment of J-Integral. The agreement for crack initiation and propagation with these test results will be discussed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.