Monte-Carlo Investigation of Avalanche in Adhesion

Abstract

ABSTRACTRecently it has been proposed that as two metal surfaces are gradually brought toward contact, atomic layers can collapse or avalanche together when the interfacial spacing falls below a critical distance. This avalanche can occur regardless of the stiffness of external supports and is accompanied by a discontinuous drop in the adhesive binding energy. Here we re-examine this phenomenon using a simple zero-temperature Monte-Carlo simulation using the Equivalent Crystal Method. In particular, we investigate the effect of loss of registry between the two contacting surfaces in order to delimit the circumstances under which avalanche can occur. We find that the avalanche is suppressed when the two surfaces are sufficiently far out of registry, at least when only a few layers near the surface are allowed to relax.