A new type of dislocation motion was found in highly-oriented pyrolytic graphite during sub-surface observation by ultrasonic atomic force microscopy. As a load was applied by the tip, apparent edge-type dislocations (Frank partial dislocations) moved in the direction of climb, over distances of 47nm, and returned to the original position as the load was removed. In order to explain this motion, a model was proposed in which the extra half-plane of the dislocation was elastically compressed so as to shorten its length due to the normal load applied by the tip.

Observation of Anomalous Dislocation Behavior in Graphite Using Ultrasonic Atomic Force Microscopy. T.Tsuji, H.Irihama, K.Yamanaka: Japanese Journal of Applied Physics - 1, 2002, 41[2A], 832-5