Localized fretting that occurs when the rolling elements of a bearing vibrate or oscillate with small amplitude while pressed against the bearing race. The mechanism proceeds in stages: 1) asperities weld, are torn apart, and form wear particles, which may then be oxidized; 2) the wear particles are abrasive and accelerate wear. The resulting wear depressions appear similar to Brinell depressions obtained with static overloading. (See also Fretting). Note: Asperities are microscopic â€œbumpsâ€ or â€œpeaksâ€ on surfaces.