Title Information
Title
Micromechanics of solid-surface contact suspension and its role in friction
Name: Personal
Name Part
Xia, Shuman
Role
Role Term: Text
creator
Origin Information
Copyright Date (keyDate="yes", encoding="w3cdtf")
2008
Physical Description
Extent
xiv, 93 p.
digitalOrigin
born digital
Note
Thesis (Ph.D.) -- Brown University (2008)
Name: Personal
Name Part
Kim, Kyung-Suk
Role
Role Term: Text
director
Name: Personal
Name Part
Bower, Allan
Role
Role Term: Text
reader
Name: Personal
Name Part
Guduru, Pradeep
Role
Role Term: Text
reader
Name: Corporate
Name Part
Brown University. Division of Engineering. Mechanics of Solids
Role
Role Term: Text
sponsor
Genre (aat)
theses
Abstract
Solid-surface contact suspension is governed by asperity contact strength and multi-frequency surface roughness. Both of these two aspects are examined in this thesis for tribological application of the solid-surface suspension technique. The research is divided into three parts. Part I focuses on the size-dependent contact strength of nano-asperities. Contact strength of nano-asperities is proposed to be mainly governed by heterogeneous dislocation nucleation due to the contact edge singularity. The dislocation model predicts that a single crystal gold pyramid with [114] facets has a contact strength scaling exponent of -0.497, which is in good agreement with the existing MD simulation result. In Part II, a novel hybrid method of nanoindentation and finite element analysis is used to characterize the silicon particle suspension resistance and the mechanical properties of Al/Si interface in an aluminum matrix composite. The suspension resistance is found to be strongly dependent on the aspect ratio, up to 2, of the buried portion of cylindrically shaped particles. The resistance comes from the plastic-flow strength of the matrix and the slip strength of the interface. The interface is found to be separated during unloading. An element-size dependent FEM cohesive-zone law is used to extract the interface properties; the results compare well with atomistic calculations. The final part of this thesis is an experimental study on micro-slip friction laws of rough surface contact with a direct quantitative measurement of the interfacial slip zone using electronic speckle pattern interferometry (ESPI). A slip precursor displacement of about 3 microns is measured before the onset of macro-slip of two contact PMMA surfaces with 1 micron RMS roughness. An apparent penetration depth under normal pressure is further observed with a contact stiffness of about 6 MPa/micron.
Subject (Local)
Topic
solid-surface contact suspension
Subject (Local)
Topic
contact strength
Subject (Local)
Topic
size effect
Subject (Local)
Topic
nanoindentation
Subject (Local)
Topic
metal matrix composites
Subject (Local)
Topic
friction laws
Subject (Local)
Topic
micro-slip
Subject (FAST) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/1017878")
Topic
Metallic composites
Record Information
Record Content Source (marcorg)
RPB
Record Creation Date (encoding="iso8601")
20091218
Language
Language Term: Code (ISO639-2B)
eng
Language Term: Text
English
Identifier: DOI
10.7301/Z0S180SW
Access Condition: rights statement (href="http://rightsstatements.org/vocab/InC/1.0/")
In Copyright
Access Condition: restriction on access
Collection is open for research.
Type of Resource (primo)
dissertations