Adhesion and Friction Using Field Ion Microscopy

Abstract

The field ion microscopy (FIM) has been applied to studies of gas adsorption, surface diffusion, transformation, alloy segregation, lattice defects, and many other research fields of surface science[1,2]. FIM studies related to tribology were first carried out by Muller and his co-workers [37]. In their experiments on metal-metal contacts inside FIM, the induced damages were analyzed in atomic detail. Buckley extended FIM studies to adhesion contact using such practical tribology materials, as PTFE etc. [810]. Ohmae et al. conducted experiments on friction contact inside the FIM, and compared friction-induced lattice defects with those analyzed in their study of adhesion contacts [11–16]. These studies have shown that FIM is uniquely suited to the study of microtribology. In FIM, a metallic tip electropolished to an apex radius of 10–100 nm is used as a sample, which may represent a single surface asperity having well-defined surface characteristics. Using a tip and a counter material, adhesion and friction can be studied in ultrahigh vacuum (UHV) environment or under conditions of gas adsorption by back-filling gas species into the chamber.