Energy and Thermodynamically Based Approaches for Analysis of Damage in Contact Problems
type: CreativeWork
description: A novel methodology for analysis of damage in contact problems in presented. Two important categories of contact damage are studied, namely crack nucleation and adhesive wear. The proposed methodology is primarily based on the laws of energy and thermodynamics, and as such offers great advantages by unifying the analysis of damage in a variety of contact configurations. Crack nucleation is the first damage type analyzed. For this purpose, the line-contact fretting configuration is chosen. A thermodynamically-based continuum damage mechanics (CDM) approach is employed. Intense stress gradients in the contact region are found to be highly influential in the crack nucleation process. A methodology is proposed that identified the averaging zone as a function of the contact and loading parameters. The predicted crack nucleation lives are verified by comparing against the published experimental data for two different alloys. The utility of the proposed methodology is also investigated for the case of rough surface contact. The deterministic approach is employed to investigate the effect of roughness on the surface tractions and contact stresses. A special averaging technique, proposed for the case of smooth surface, is adopted. The predictions of the crack nucleation life for different roughness values are compared with relevant experimental data in literature, and confirm the validity of the analysis. Adhesive wear is another type of contact damage investigated. The study is carried out for three different contact conditions. These include disk-on-disk unidirectional dry sliding, pin-on-flat reciprocating dry sliding and pin-bushing grease-lubricated oscillatory sliding. It is shown that the wear rate is linearly related to the power dissipation as well as the entropy generation rate. The linear correlations are verified experimentally. Degradation coefficient is obtained and a simple approach is proposed for prediction of wear in dry sliding configuration. The proposed …
abstract: A novel methodology for analysis of damage in contact problems in presented. Two important categories of contact damage are studied, namely crack nucleation and adhesive wear. The proposed methodology is primarily based on the laws of energy and thermodynamics, and as such offers great advantages by unifying the analysis of damage in a variety of contact configurations. Crack nucleation is the first damage type analyzed. For this purpose, the line-contact fretting configuration is chosen. A thermodynamically-based continuum damage mechanics (CDM) approach is employed. Intense stress gradients in the contact region are found to be highly influential in the crack nucleation process. A methodology is proposed that identified the averaging zone as a function of the contact and loading parameters. The predicted crack nucleation lives are verified by comparing against the published experimental data for two different alloys. The utility of the proposed methodology is also investigated for the case of rough surface contact. The deterministic approach is employed to investigate the effect of roughness on the surface tractions and contact stresses. A special averaging technique, proposed for the case of smooth surface, is adopted. The predictions of the crack nucleation life for different roughness values are compared with relevant experimental data in literature, and confirm the validity of the analysis. Adhesive wear is another type of contact damage investigated. The study is carried out for three different contact conditions. These include disk-on-disk unidirectional dry sliding, pin-on-flat reciprocating dry sliding and pin-bushing grease-lubricated oscillatory sliding. It is shown that the wear rate is linearly related to the power dissipation as well as the entropy generation rate. The linear correlations are verified experimentally. Degradation coefficient is obtained and a simple approach is proposed for prediction of wear in dry sliding configuration. The proposed …
author: Babaie Aghdam, Afshin
keywords: friction, energy approach, thermodynamic approach, entropy generation, contact mechanics, wear, crack nucleation, fretting, surface roughness
date published: 2014-01-01T08:00:00Z
date modified: 2026-07-24T02:59:31Z
provider: Lousiana State University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Mechanical Engineering

PropertyValue
property ID: DOI
value: 10.31390/gradschool_dissertations.1438