Measurement of effective stress intensity factor range of Mode II fatigue crack propagation

Many rolling contact fatigue failures, such as those that occur in railway rails, rolling bearings and gears, is due to the high repeated shear load. In order to prevent such fatigue a failure, the resistance of the material against such a load must be determined. The fatigue crack growth rate is dependent on the stress intensity factor range of the Mode II Δ K_II. However, the Mode II crack propagation characteristic varies according to different experiment methods. Therefore, in this study, we measured the effective stress intensity factor range of the Mode II Delta; K_IIeff. As it is difficult to carry out the Mode II fatigue crack propagation in the laboratory, this test was carried out using a bending load in this study. This bending load was applied to the tips of a double cantilever specimen and the Mode II fatigue crack propagation could be carried out between the two cantilevers. Furthermore, in order to measure the Δ K_IIeff, several strain gauges were applied to the specimen around the crack tip. Using this technique, some Δ K_IIeff value during the Mode II fatigue crack propagation tests will be reported.