Model for Adhesion-Based Energy Dissipation During Friction
Michael Nosonovsky, Stephen M. Hsu
Adhesion plays a significant role in Nanoscale interfacial friction for basically non-adhesive surfaces (no chemical bonding). The adhesion forces are composed of van der Waals forces and the contact force from surface contact. The van der Waals forces are basically conservative and by themselves do not provide energy dissipation process. The contact forces depend on surfaces atomic configuration, surface energy distribution, and the real area of contact. This is fundamentally the cause for the observed adhesion hysteresis. In this paper we propose to use the adhesion hysteresis as an energy dissipation mechanism for interfacial friction. We consider a contact of a rigid cylinder, representing asperity, with an elastic plane, using the Dugdale approximation. The plane is modeled by continuously distributed elastic springs. For both sliding and rolling contacts, adhesive force at the rear of the cylinder is greater than at the front, which results in frictional resistance and energy dissipation due to excitation of elastic oscillations. The relationship among adhesion, adhesion hysteresis, and friction is discussed.