Mechanics of dislocations in multilayered materials

This thesis reports an investigation into the mechanics of anisotropic multilayered materials embedded with dislocations. An image technique is developed for solving the problems of infinite bilayers, film-substrates and general N-layer composites. The key contributions are: (1) the development of a...

Full description

Saved in:
Bibliographic Details
Main Author: Wang, Huyi
Other Authors: Wu Mao See
Format: Theses and Dissertations
Published: 2008
Subjects:
Online Access:https://hdl.handle.net/10356/5284
Tags: Add Tag
No Tags, Be the first to tag this record!
Institution: Nanyang Technological University
id sg-ntu-dr.10356-5284
record_format dspace
spelling sg-ntu-dr.10356-52842023-03-11T17:43:25Z Mechanics of dislocations in multilayered materials Wang, Huyi Wu Mao See School of Mechanical and Aerospace Engineering DRNTU::Engineering::Materials::Metallic materials This thesis reports an investigation into the mechanics of anisotropic multilayered materials embedded with dislocations. An image technique is developed for solving the problems of infinite bilayers, film-substrates and general N-layer composites. The key contributions are: (1) the development of an image decomposition scheme which is instrumental to the accuracy of the complete solution, and (2) the elimination of singularities from the governing integral equations using certain H and I transforms. Numerical investigations reveal that many factors, e.g., elastic anisotropy and layer inhomogeneity, will significantly influence the image forces acting on the dislocation. Furthermore, a single-ended discrete dislocation pileup model is developed and used to show that the shear strength dependence on layer thickness obeys the Hall-Petch relation quite well for sufficiently thick layers while image forces result in a deviation of the relation for very thin layers. The numerical predictions are in good agreement with a comprehensive set of experimental data for metallic multilayer systems. DOCTOR OF PHILOSOPHY (MPE) 2008-09-17T10:47:03Z 2008-09-17T10:47:03Z 2007 2007 Thesis Wang, H. (2007). Mechanics of dislocations in multilayered materials. Doctoral thesis, Nanyang Technological University, Singapore. https://hdl.handle.net/10356/5284 10.32657/10356/5284 Nanyang Technological University application/pdf
institution Nanyang Technological University
building NTU Library
continent Asia
country Singapore
Singapore
content_provider NTU Library
collection DR-NTU
topic DRNTU::Engineering::Materials::Metallic materials
spellingShingle DRNTU::Engineering::Materials::Metallic materials
Wang, Huyi
Mechanics of dislocations in multilayered materials
description This thesis reports an investigation into the mechanics of anisotropic multilayered materials embedded with dislocations. An image technique is developed for solving the problems of infinite bilayers, film-substrates and general N-layer composites. The key contributions are: (1) the development of an image decomposition scheme which is instrumental to the accuracy of the complete solution, and (2) the elimination of singularities from the governing integral equations using certain H and I transforms. Numerical investigations reveal that many factors, e.g., elastic anisotropy and layer inhomogeneity, will significantly influence the image forces acting on the dislocation. Furthermore, a single-ended discrete dislocation pileup model is developed and used to show that the shear strength dependence on layer thickness obeys the Hall-Petch relation quite well for sufficiently thick layers while image forces result in a deviation of the relation for very thin layers. The numerical predictions are in good agreement with a comprehensive set of experimental data for metallic multilayer systems.
author2 Wu Mao See
author_facet Wu Mao See
Wang, Huyi
format Theses and Dissertations
author Wang, Huyi
author_sort Wang, Huyi
title Mechanics of dislocations in multilayered materials
title_short Mechanics of dislocations in multilayered materials
title_full Mechanics of dislocations in multilayered materials
title_fullStr Mechanics of dislocations in multilayered materials
title_full_unstemmed Mechanics of dislocations in multilayered materials
title_sort mechanics of dislocations in multilayered materials
publishDate 2008
url https://hdl.handle.net/10356/5284
_version_ 1761781914106068992