Adhesive Elastic–Plastic Microcontact Analysis of Truncated Cylinder-on-Flat with Asperities

Abstract

Adhesion interaction during micro-contacts of deformable rough bodies is characterized in this study using finite element based methodology. The interacting bodies are a truncated cylinder and a flat. Surfaces roughness is simulated by multiple asperities on a cylindrical segment. Lennard–Jones potential methodology is used to calculate adhesion forces by volume integration over the contacting bodies as well as over all asperities, both undeformed and deformed. Cylindrical segment of the asperity is deformed basically in two cylindrical segments. The flat body is deformed the least at the center and maximum at the outer portion of contact width, causing concave bending of the upper body with multi-asperity interfaces. Radius of asperities decreases from the center to outer periphery along the contact width. Adhesion force at each asperity is minimum at the center and maximum at the outer portion of the contact width in the deformed state after complete unloading. The total adhesion force between all asperities and lower body depends on number of asperities, and its maximum value decreases after deformation and occurs at separation distance greater than that for undeformed contact. Its maximum value increases with increasing number of asperities for the undeformed state and decreases with increasing number of asperities for the deformed state. On the other hand, total adhesion force between asperities, truncated cylindrical body and lower body increases with increasing number of asperities for both undeformed and deformed states due to the contribution of truncated segment/lower body interaction, and its location shifts towards the center of contact with increasing number of asperities.