Chemical Physics Letters, Vol.514, No.4-6, 325-329, 2011
Shear-induced lamellar ordering and interfacial sliding in amorphous carbon films: A superlow friction regime
A shear-induced phase transition from disorder to lamellar ordering in amorphous carbon films are investigated by molecular dynamics simulations. Formation of well-separated graphene-like interfacial layers is observed with large interlayer distances, diminishing and ultimately vanishing interlayer bonds, which provides a near-frictionless sliding plane. The steady-state velocity accommodation mode after the running-in stage is interfacial sliding between the graphene-like layers, which explains the experimentally observed graphitization and formation of carbon-rich transfer layers. A superlow friction or superlubricity regime with friction coefficient of approximately 0.01 originates from the extremely large repulsive and low shear interactions across the sliding interface. (C) 2011 Elsevier B. V. All rights reserved.