The premise of the continuum damage mechanics (CDM) model for rolling contact fatigue (RCF) is based on the hypothesis that the damage mechanisms for torsion fatigue and rolling contact fatigue are equivalent. Mr. Lewis commented that the verification of this hypothesis has not been carried out within the paper. However, the reasoning behind such hypothesis has been explained in many papers authored by Sadeghi et al. [1–6]. For the readers' benefit, the explanation is provided here in brief.
In the case of subsurface-initiated RCF, cracks initiate in the region of maximum shear stress [3]. Figure 1 depicts the stress distribution for a loading pass at the depth of maximum shear stress for a 2D line contact under plane strain conditions. It can be seen that the shear stress, τxy, is the only component of stress that undergoes a complete reversal, while the...