Finite element modeling of adhesive contact using molecular potential

Abstract A finite element technique for analysis of adhesive contact is developed in which the adhesive force is modeled as a body force derived from Lennard–Jones 12–6 potential. Adhesive contact of an elastic hemispherical asperity with the plane surface of a semi-infinite rigid body is analyzed. Variations of the interaction force and contact radius during approach and withdrawal, and the dependence of pull-off force on the asperity radius are shown to be in good agreement with those of Maugis–Dugdale model. Analysis results reveal that smaller asperity is superior for preventing stiction and for reducing adhesive friction, but is subject to more severe adhesive wear. It is anticipated that this technique can be utilized in designing a low-adhesion surface profile for MEMS applications since the effect of various surface geometries can be examined.