In rolling contact fatigue (RCF), cyclic plastic deformation is caused by cyclic rolling contact, the texture develops, and the fatigue crack propagates in the texture under Mode II loading. As fatigue crack propagation under Mode II loading occurs inside the material, direct observation is difficult. Roughness-induced stress shielding (RISS) effect influences the fatigue crack propagation in RCF. However, as it is difficult to observe fatigue cracks in RCF directly, quantitative evaluation of RISS is difficult. Therefore, in this study, quantitative evaluation of RISS was performed by using a test method that enables direct observation of the fatigue crack propagation behavior under Mode II loading. In an actual machine in which RCF occurs, the texture has been generated. Hence, a material having texture was used for the test. From the results of the test, it was observed that the fatigue crack propagated in the same direction as the pre-crack. Therefore, fatigue crack propagation is considered to be successfully reproduced under Mode II loading. From a quantitative calculation result of the reduction rate of the stress intensity factor range owing to the contact between fracture surfaces by using the shape of the obtained fatigue crack shape and the assumed deformation shape, the reduction rate was determined to be very low. Therefore, the influence of RISS on the stress intensity factor range is considerably small, and it is considered that RISS does not exist in fatigue crack propagation under Mode II loading of a material having texture.
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