Sliding contact at plastically graded surfaces and applications to surface design

Tailored gradation in elastic-plastic properties is known to offer avenues for suppressing surface damage during normal indentation and sliding contact. These graded materials have potential applications in diverse areas such as barrier coatings for structural components and industrial tools. The gradient in plastic properties is of greater significance for such tribological applications due to the higher level of plastic strains. However, no systematic study exists to predict the impact of plastic gradients for such abrasive events. Such a study is required, both for a fundamental understanding of the plastic gradient effects, and for a practical requirement of the design of graded surfaces. In this work, the effects of the plastic gradient on the surface deformation and hardness response are investigated through systematic experiments and simulations of the scratch test. For the case of the linear increase in the yield strength, some of the fundamental questions related to the mechanism of behavior are addressed, and its implications in the design of graded surfaces are discussed. Through derivation of dimensionless functions, a simple framework is developed to predict the scratch test response of such materials.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Civil and Environmental Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Prasad, Anamika, 1979-

Advisor dc:contributor.advisor

• Subra Suresh.

• Civil and Environmental Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/39260

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/39260