BSTRACTThis letter reports that a pre-notched WS

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/a-C tribocoating surface can be fully healed through sliding. The healed notches act as superior lubricant micro-reservoirs affording frictionless responses leading to an ultralow coefficient of friction (0.02). HR-TEM observations reveal WS

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(002) platelets in the healed notch parallel to the outer coating surface and to the V-notch/coating interface. Direct evidence of the rearrangement of WS

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at the curved interface elucidates that basal plane reorientation does not occur necessarily parallel to the counterpart sliding direction as was taken for granted in literature. The patchy tribofilm provides a new avenue for self-healing efficiency in tribology.