Anomalous increase of friction in the vicinity of nano-size defects
نویسنده
چکیده
A new phenomenon, anomalous increase of static friction in the vicinity of atomic defects, is studied by means of molecular simulations. It is found that an apex of a single asperity contact becomes “trapped” in the vicinity of a defect provided the normal force acting between the apex and surface is above some critical value. Examples of an atomic vacancy and a step are analyzed. The anomaly is the result of non-trivial force interaction near defects. Considered dynamically, the effect can result in additional wearing during sliding.
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