CUED Publications database

Discrete dislocation plasticity analysis of loading rate-dependent static friction.

Song, H and Deshpande, VS and Van der Giessen, E (2016) Discrete dislocation plasticity analysis of loading rate-dependent static friction. Proc Math Phys Eng Sci, 472. 20150877-. ISSN 1364-5021

Full text not available from this repository.

Abstract

From a microscopic point of view, the frictional force associated with the relative sliding of rough surfaces originates from deformation of the material in contact, by adhesion in the contact interface or both. We know that plastic deformation at the size scale of micrometres is not only dependent on the size of the contact, but also on the rate of deformation. Moreover, depending on its physical origin, adhesion can also be size and rate dependent, albeit different from plasticity. We present a two-dimensional model that incorporates both discrete dislocation plasticity inside a face-centred cubic crystal and adhesion in the interface to understand the rate dependence of friction caused by micrometre-size asperities. The friction strength is the outcome of the competition between adhesion and discrete dislocation plasticity. As a function of contact size, the friction strength contains two plateaus: at small contact length [Formula: see text], the onset of sliding is fully controlled by adhesion while for large contact length [Formula: see text], the friction strength approaches the size-independent plastic shear yield strength. The transition regime at intermediate contact size is a result of partial de-cohesion and size-dependent dislocation plasticity, and is determined by dislocation properties, interfacial properties as well as by the loading rate.

Item Type: Article
Uncontrolled Keywords: adhesion discrete dislocation plasticity friction strength loading rate
Subjects: UNSPECIFIED
Divisions: Div C > Materials Engineering
Depositing User: Cron Job
Date Deposited: 17 Jul 2017 19:37
Last Modified: 19 Sep 2017 01:30
DOI: