Friction force microscopy

✍ Scribed by Roland Bennewitz

• Book ID: 104417406
• Publisher: Elsevier Science
• Year: 2005
• Tongue: English
• Weight: 817 KB
• Volume: 8
• Category: Article
• ISSN: 1369-7021
• DOI: 10.1016/s1369-7021(05)00845-x

✦ Synopsis

Friction between sliding bodies is the result of the collective and quite possibly interdependent mechanical behavior of a multitude of small contacts between shearing surfaces, which are constantly being formed, deformed, and ruptured. The time scales for these local transformations range from the lifetime of individual microscopic contacts over the periods of mechanical resonances in the sliding bodies all the way down to those of molecular vibrations. The necessary complexity in descripting the nonlinear nature of friction has recently been reviewed by Urbakh and coworkers 1 . Several experimental methods attempt to provide microscopic input into these descriptions by measuring the forces involved in the sliding of single asperity contacts. For example, indentation experiments use ultrahard tips and wellcontrolled, rigid mechanical setups to reveal the elastic and plastic response of surfaces to a probing tip 2 , while the surface forces apparatus studies friction in micron-scale contacts between atomically smooth curved surfaces, providing perfect control over contact size and structure 3 .

The instrument that is subject of this report, the friction force microscope, is a variation of the atomic force, or scanning probe, microscope (AFM or SPM) 4 . Its role is to measure friction in the smallest sliding contacts and provide sensitivity that justifies the name atomic force microscope. Atomic forces that act in the sliding of few-atom contacts may then provide very direct insight into the microscopic