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Fig. 5. Flaking damage on the outer raceway of a roller bearing.

Fig. 6. Localized flaking damage on the inner ring of a thrust bearing

generally found to be associated with pitting originating from surface stress concentration sites. In
roller bearings, flaking sometimes occurs along a ring on a plane corresponding to the end of the
rollers. This indicates that the bearing is misaligned, and the loads unevenly distributed. Finally,
flaking damage is occasionally found at regular intervals corresponding to the rolling element
spacing. In these cases, damage is associated with indentations produced when the stationary bearing
is loaded, these indentations being referred to as true brinnelling.
Another form of severe contact fatigue damage is known as spalling. As in the case of gear teeth
[l], spalling occurs as a progression of the pits formed by rolling and rolling-sliding contact fatigue,