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Dissertations / Theses on the topic 'Grain materials'

Author: Grafiati

Published: 28 May 2022

Last updated: 31 July 2025

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1

Ouyang, Hao Fultz B. Fultz B. "Grain boundaries of nanophase materials /." Diss., Pasadena, Calif. : California Institute of Technology, 1993. http://resolver.caltech.edu/CaltechETD:etd-08312007-095729.

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2

Morris, Billy Ray. "Grain size estimation in anisotropic materials." Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/20042.

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3

Sarrazit, Franck. "Structure of grain boundaries in hexagonal materials." Thesis, University of Liverpool, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367291.

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4

Johnson, Oliver Kent. "Grain boundary network design." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/98740.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2015.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (pages 117-133).<br>Grain boundaries in polycrystals form a complex interconnected network of intercrystalline interfaces. The crystallographic character of individual grain boundaries and the network structure of the grain boundary ensemble have been experimentally observed to have a strong influence on many materials properties. This observation suggests that if we could control the types of grain boundar

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5

Swisher, Douglas Lee. "Deformation banding and grain refinement in FCC materials." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Mar%5FSwisher.pdf.

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6

Kelly, Madeleine N. "The Temperature Dependence of Grain Boundary Complexion Transitions and Their Effect on the Grain Boundary Character and Energy Distributions." Thesis, Carnegie Mellon University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10604582.

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<p> Abrupt changes in grain boundary energy (GBE) and character are associated with a change in GB complexion, GB mobility and exaggerated grain growth. In this thesis, complexion transitions and their effect of relative GBE and GB character distributions (GBCD) are studied for ceramics: europium doped spinel (Eu doped spinel), yttria doped (Y-doped), undoped alumina (Al<sub> 2</sub>O<sub>3</sub>), and strontium titanate (SrTiO<sub>3</sub>). </p><p> The population of GB planes (GBPD) of Eu doped spinel was investigated at temperatures before and after a previously identified a complexion tra

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7

Bhatt, Jayesh S., and Marc-Olivier Coppens. "Diffusion at tilt grain boundaries in polycrystalline porous materials." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-198033.

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8

Bhatt, Jayesh S., and Marc-Olivier Coppens. "Diffusion at tilt grain boundaries in polycrystalline porous materials." Diffusion fundamentals 24 (2015) 6, S. 1, 2015. https://ul.qucosa.de/id/qucosa%3A14520.

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9

Patala, Srikanth. "Topological analysis of the grain boundary space." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/69667.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2011.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 117-125).<br>Grain boundaries and their networks have a profound influence on the functional and structural properties of every class of polycrystalline materials and play a critical role in structural evolution and phase transformations. Recent experimental a

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10

Lee, Wing-Yan Dona. "Computer simulation of grain boundaries in rutile." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/28052.

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11

Chen, Long-Qing 1962. "Molecular dynamics study of ionic grain boundaries." Thesis, Massachusetts Institute of Technology, 1990. https://hdl.handle.net/1721.1/128799.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1990.<br>Includes bibliographical references (leaves 240-244).<br>by Long-Qing Chen.<br>Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1990.

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12

Ma, Xun 1952. "Sintering and grain growth behaviour of Si3N4 ceramics." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=56789.

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During sintering, $ rm Si sb3N sb4$ transforms through a liquid phase from the metastable $ alpha$ phase to the stable $ beta$ phase. In this work, $ rm Y sb2O sb3, Al sb2O sb3$ and AlN were added as liquid-forming additives, which react with surface SiO$ sb2$ on the $ rm Si sb3N sb4$ particles. The mechanism of pressureless sintering $ rm Si sb3N sb4$ with these additives was a combination of particle rearrangement, solution-precipitation and elimination of closed porosity. The rate of densification and $ alpha$-$ beta$ phase transformation were strongly influenced by the amount and viscosity

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13

Gao, Si. "Yield Point Phenomena in Ultrafine Grained Materials." 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215534.

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14

Frary, Megan. "Crystallographically consistent percolation theory for grain boundary networks." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33402.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2005.<br>Includes bibliographical references (p. 127-134).<br>Grain boundaries are known to play a role in many important material properties including creep resistance, ductility and cracking resistance. Although the structure and properties of individual boundaries are important, the overall behavior of the material is determined largely by the connectivity of grain boundaries in the microstructure. Grain boundary networks may be studied in the framework of percolation theory by classifying bo

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15

Carel, Roland. "Grain growth and texture evolution in thin films." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/31064.

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16

Powers, Max L. (Max Lyle). "Modeling tin sulfide grain growth during post-processing." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/89978.

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Thesis: S.B., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2014.<br>Cataloged from PDF version of thesis. "June 2014."<br>Includes bibliographical references (pages 32-33).<br>Tin sulfide (SnS) is a semiconductor material with both an indirect and direct bandgap at 1.1 eV and 1.3 eV respectively. Due to the availability of tin and sulfur, SnS is seen as a feasible alternative to the thin film CIGS and CdTe solar cells. With a direct bandgap of 1.1 eV and the ability to be produced as a thin film, the SnS solar cell should achieve high levels of effici

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17

Rezvanian, Omid. "GRAIN SUBDIVISION AND MICROSTRUCTURAL INTERFACIAL SCALE EFFECTS IN POLYCRYSTALLINE MATERIALS." NCSU, 2006. http://www.lib.ncsu.edu/theses/available/etd-01052006-204245/.

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The major objective of this research is to develop a unified physically-based representation of the microstructure in f.c.c. crystalline materials to investigate finite inelastic deformation and failure modes and scenarios at different physical scales that occur due to a myriad of factors, such as texture, grain size and shape, grain subdivision, heterogeneous microstructures, and grain boundary misorientations and distributions. The microstructurally-based formulation for inelastic deformation is based on coupling a multiple-slip crystal plasticity formulation to three distinct dislocation de

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18

Hanlon, Timothy 1977. "Grain size effects on the fatigue response of nanocrystalline materials." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/16635.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2004.<br>Includes bibliographical references (p. 151-158).<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>The resistance of metals and alloys to fatigue crack initiation and propagation is known to be influenced significantly by grain size. Based on a wealth of experimental results obtained from microcrystalline metals, where the grain size is typically greater than 1 um, it is widely recogn

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19

Tikare, Veena. "Numerical simulation of grain growth in liquid phase sintered materials." Case Western Reserve University School of Graduate Studies / OhioLINK, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=case1058549001.

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20

Vazquez, Isaura 1960. "On aluminum grain boundary structure and segregation." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/291693.

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The effect of an alloying agent, such as Mg, on Al grain boundary microstructure and chemistry was investigated. HREM measurements on an Al-5% Mg Σ = 5 (310) grain boundary showed Al grain boundary structure modification because of the presence of Mg. Chemical analysis, through TEM/STEM EDS of Al-2% Mg alloy, indicated the possibility of Mg segregation at Al grain boundaries, although this should be further investigated. An experiment is proposed to determine the change in grain boundary torque with impurity chemical potential. Molecular dynamic simulations of the effect of segregated vacancie

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21

Wong, Chee Cheong. "Secondary grain growth and graphoepitaxy in thin Au films." Thesis, Massachusetts Institute of Technology, 1986. http://hdl.handle.net/1721.1/80446.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1986.<br>MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE<br>Bibliography: leaves 276-283.<br>by Chee Cheong Wong.<br>Ph.D.

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22

He, Youliang. "Grain-scale characterization of FCCBCC correspondence relations and variant selection." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=85916.

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The misorientations between FCC and BCC crystals are characterized according to the common lattice correspondence relationships in terms of their parallelism conditions. Individual variants of the six models, namely the Bain, Kurdjumov-Sachs, Nishiyama-Wassermann, Pitsch, Greninger-Troiano and inverse Greninger-Troiano relations, are identified and represented in both pole figure form and in Rodrigues-Frank space with respect to various coordinate frames. In this way, the relations between the variants of these models are clarified.<br>The orientations of the kamacite (BCC) lamellae tran

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23

Lin, Peter Keng-Yu. "Evolution of grain boundary character distributions in FCC and BCC materials." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ27994.pdf.

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24

Csati, Zoltan. "Mesh-independent modelling of diffuse cracking in cohesive grain-based materials." Thesis, Ecole centrale de Nantes, 2019. http://www.theses.fr/2019ECDN0037.

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Dans cette thèse, une formulation stable mixte de déplacement–multiplicateur de Lagrange est développée pour modéliser la fissuration dans les matériaux cohésifs à grains dans le cadre de la méthode des éléments finis etendus (CutFEM). Le champ de déplacement est discrétisé sur chaque grain individuellement, et la continuité des champs de déplacement et de traction aux interfaces entre grains est assurée par des multiplicateurs de Lagrange. La construction de l'espace discret des multiplicateurs de Lagrange est détaillée pour les éléments quadrangulaires bilinéaires avec la présence d’interfac

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25

Mizera, J., P. Maj, and B. Adamczyk-Cieslak. "Comparison of Grain Refinement in Selected Materials Subjected to Hydrostatic Extrusion." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35600.

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The subject of this study was to examine and compare the impact of intense hydrostatic extrusion on grain refinement in three different alloys: duplex stainless steel, commercially used aluminum alloy (6060) and Ag-Cu12 alloy. As a result of the process grain sizes from 370 nm to 90 nm were obtained in aluminum and duplex steel. To analyze the of hydrostatic on mechanical properties tensile tests were also carried out. The highest grain refinement (70 nm) and yield strength increase (over 300%) was observed in duplex steel af-ter hydrostatic extrusion. When you are citing the document, use the

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26

Keller, Trevor. "Bias in polycrystal topology caused by grain boundary motion by mean curvature." Thesis, Rensselaer Polytechnic Institute, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3705608.

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<p> During heat treatment of polycrystalline materials, grain shape affects the rate of grain growth. In 2-D, the von Neumann-Mullins Law requires grains with fewer than six edges to shrink, greater than six edges to grow, and hexagonal grains to be stable regardless of edge lengths or curvatures. The 3-D analogue, described by the MacPherson-Srolovitz relation, does not explicitly depend on any topological feature (number of faces, edges, or vertices), yet there is bias in the observed grain topologies in 3-D metal polycrystals. In order to investigate this bias and determine its origins, num

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27

Dolhert, Leonard E. "Oxygen diffusion in dislocations and grain boundaries in magnesium oxide." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/70617.

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28

Gore, Mark John. "Grain-refining dispersions and mechanical properties in ultrahigh-strength steels." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/14573.

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29

Ueland, Stian Melhus. "Grain constraint and size effects in shape memory alloy microwires." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/80893.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2013.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Cataloged from student-submitted PDF version of thesis.<br>Includes bibliographical references (p. 142-147).<br>Shape memory alloys exhibit interesting and useful properties, such as the shape memory effect and superelasticity. Among the many alloy families that have been shown to exhibit shape memory properties the ones based on copper ar

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30

Figueroa, Oscar III. "Variations in grain boundary segregation for nanocrystalline stability and strength." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/76179.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2012.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 39).<br>In the last few decades, nanocrystalline metals have been of increasing interest. Their ability to show increased yield strength and uniform structure show them to be potentially useful in many applications. Additionally, nanocrystalline metals have become more easily manufactured in recent years, allowing for more testing and more use within industrial settings. However, nanocrystalline metals are st

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31

Kvam, Eric Peter. "TEM study of dislocation structure in grain boundaries in metals." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/15325.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1985.<br>MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.<br>Vita.<br>Bibliography: leaves 150-154.<br>by Eric Peter Kvam.<br>Ph.D.

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32

Blom, Doughas A. (Douglas Allen) 1971. "Grain boundary chemistry and morphology of heavily doped cerium dioxide." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/9580.

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Thesis (Sc.D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1998.<br>Includes bibliographical references (p. 135-142).<br>Ceria is a model system for oxygen ion conducting ceramics of the cubic fluorite structure, in which grain boundaries are known to limit the overall ionic conductivity of polycrystals. Measurements of grain boundary segregation of the aliovalent dopants Gd3+ and Ta5+ in heavily doped ceria have been made using a Vacuum Generators HB603 scanning transmission electron microscope (STEM). Space charge models both at the dilute limit, and w

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33

Zhong, Yuan. "Sub-grain structure in additive manufactured stainless steel 316L." Doctoral thesis, Stockholms universitet, Institutionen för material- och miljökemi (MMK), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-144519.

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The thesis focuses on exploring the sub-grain structure in stainless steel 316L prepared by additive manufacturing (AM). Two powder-bed based AM methods are involved: selective laser melting (SLM) and electron beam melting (EBM). It is already known that AM 316L has heterogeneous property and hierarchy structure: micro-sized melt pools, micro-sized grains, nano-sized sub-grain structure and nano-sized inclusions. Yet, the relation among these structures and their influence on mechanical properties have not been clearly revealed so far. Melt pool boundaries having lower amount of sub-grain segr

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34

Tucker, Garritt J. "Atomistic simulations of defect nucleation and free volume in nanocrystalline materials." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41107.

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Atomistic simulations are employed in this thesis to investigate defect nucleation and free volume of grain boundaries and nanocrystalline materials. Nanocrystalline materials are of particular interest due to their improved mechanical properties and alternative strain accommodation processes at the nanoscale. These processes, or deformation mechanisms, within nanocrystalline materials are strongly dictated by the larger volume fraction of grain boundaries and interfaces due to smaller average grain sizes. The behavior of grain boundaries within nanocrystalline materials is still largely unkn

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35

Laukli, Hans Ivar. "High Pressure Die Casting of Aluminium and Magnesium Alloys : Grain Structure and Segregation Characteristics." Doctoral thesis, Norwegian University of Science and Technology, Department of Materials Technology, 2004. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-379.

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<p>Cold chamber high pressure die casting, (HPDC), is an important commercial process for the production of complex near net shape aluminium and magnesium alloy castings. The work presented in the thesis was aimed at investigating the microstructure formation in this type of casting. The solidification characteristics related to the process and the alloys control the formation of grains and defects. This again has a significant impact on the mechanical properties of the castings.</p><p>The investigations were carried out mainly using the AM60 magnesium alloy and the A356 aluminium alloy. Two d

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36

Kaplin, Cory. "The effect of grain refinement on the oxidation performance of MCrAlY alloys." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=123004.

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MCrAlY's are a specific class of nickel-based superalloy primarily used as a thermal barrier coating (TBC) bond coat or for oxidation resistance. The focus of this thesis is to study the improvement of high temperature oxidation and corrosion performance of MCrAlY and related alloys through nanostructuring, from understanding the oxidation mechanism of grain refined materials to evaluation of their performance in a simulated service environment. Grain refinement of the metal substrate was shown to favour the formation of a single oxide layer of α-alumina that can prevent the formation of fast

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37

Chung, Yong-Chae. "Toward the measurement of reliable grain-boundary diffusion coefficients in oxides." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/38105.

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38

Soontrapa, Chaiyod. "Modeling stress accelerated grain boundary oxidation (SAGBO) in INCOLOY alloy 908." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33613.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2005.<br>Includes bibliographical references (p. 57-59).<br>This study explores the possibility of extending the Ph.D. work of Yan Xu on copper-tin alloys (University of Pennsylvania, 1999) to model stress accelerated grain boundary oxidation (SAGBO) in INCOLOY alloy 908. The steady state model involves the embrittlement along the grain boundary due to oxygen diffusion with the concentration gradient and the stress field ahead of the crack tip as the driving forces. As oxygen forms brittle phases

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39

Zelinski, Jeffrey A. "An evaluation of grain boundary engineering technology and processing scale-up." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33616.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2005.<br>Includes bibliographical references (p. 50-52).<br>Grain boundary engineering is the manipulation of low stacking-fault energy, face- centered cubic material microstructures to break the connectivity of the general grain boundary network through the addition of special grain boundaries. Grain boundary engineering processing consists of thermomechanical cycling, i.e. repeated strain and annealing sequences and provides a method of producing more robust polycrystalline materials. This ev

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40

Detor, Andrew J. (Andrew Joseph). "Grain size control and microstructural evolution in nanocrystalline Ni-W alloys." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/39547.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2007.<br>Includes bibliographical references (leaves 119-131).<br>Nanocrystalline materials have been studied extensively over the past two decades because of their useful and interesting physical properties. In most cases, these properties derive from the fine characteristic length scale of nanocrystalline structures and are superior to those realized in traditional coarse-grained materials. A fundamental challenge, however, involves the synthesis of high-quality specimens, which represent a cl

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41

Osman, Hoch Bachir. "Modelling of hydrogen diffusion in heterogeneous materials : implications of the grain boundary connectivity." Thesis, La Rochelle, 2015. http://www.theses.fr/2015LAROS030/document.

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La diffusion de l’hydrogène dans les métaux est un paramètre clef pour la compréhension des mécanismes de base de la fragilisation par l’hydrogène. Néanmoins, le rôle des joints de grains dans le processus de diffusion de cet élément reste à éclaircir. Avec une approche numérique, nous avons étudié les effets d’un réseau hétérogène de joints de grains sur la diffusivité macroscopique de l’hydrogène. Pour cela, des essais de perméation ont été simulés par la méthode des éléments finis, en modélisant le matériau comme un composite formé d’une phase intra-associée aux grains et deux phases interg

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42

Carlsson, Sofia. "Grain refinement of aluminium by titanium diboride particles : The importance of nucleation, growth restriction, and cooling rate." Thesis, KTH, Materialvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-266096.

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The grain refinement of aluminium by titanium diboride particles, TiB2, using Ti/B grain refiners is common practice in the aluminium industry, but exactly how this grain refinement is achieved is uncertain. Current addition of grain refiner is therefore rarely optimal and excessive addition rates of grain refiner is common. This study investigates grain refinement of aluminium by titanium diboride to create a method and/or model which can be used to aid in addition rate optimisation. The effect of different parameters on grain refinement is the focus and includes cooling rate, properties of t

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43

Cox, Melissa Reiko Brooke. "The Influence of Grain Shape on Dilatancy." Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/195563.

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Grain shape is a key factor affecting the mechanical properties of granular materials. However, grain shape quantification techniques to distinguish one granular material from another have not reached a stage of development for inclusion in modeling the behavior of granular materials. Part of the problem is the equipment of choice for grain shape measurement is the scanning electron microscope. This is a relatively expensive and complex device. In this research, a practical approach using light microscopy to quantify grain shape and to identify the key shape parameters that can distinguish

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44

Jiang, Junnan. "Micro- and macro-mechanical testing of grain boundary sliding in a Sn-Bi alloy." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:df0fc17f-850b-44dc-b743-92573b82542b.

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This project explores the fundamental mechanisms of grain boundary sliding (GBS) with an emphasis on its role in superplasticity, using both micro- and macro-mechanical testing methods. GBS plays an important role in the deformation of polycrystalline materials, especially at high homologous temperatures (above half of the melting point). Classical models for GBS (Rachinger sliding and Lifshitz sliding) assume that all grains and grain boundaries undergo the same process, but recent research has shown this is not true. Individual grain boundaries differ in their ability to participate in slidi

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45

Illingsworth, J. S. "Investigation of the grain boundary layer characteristics of donor doped barium titanate ceramics." Thesis, Durham University, 1990. http://etheses.dur.ac.uk/1118/.

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Donor doped barium titanate ceramics are well known for their Positive Temperature Coefficient of Resistance (PTCR) characteristic above the crystallographic transition temperature, T° '130°C, where the material changes from the ferroelectric state to paraelectric. The shape and magnitude of the PTCR characteristic are known to be dependent on the composition and preparation of the ceramic, the presence of impurities, particularly donor dopant concentration and acceptor ions, and the sintering conditions. Thirty years ago Heywang proposed a model based on the presence of two-dimensional resist

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46

Leib, Jeffrey Scott. "Relationships between grain structure and stress in thin Volmer-Weber metallic films." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/46682.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2009.<br>Includes bibliographical references (leaves 150-154).<br>In Volmer-Weber growth, islands that nucleate on the substrate surface impinge and coalesce into grains of a continuous film. During deposition of these polycrystalline films, the intrinsic stress for materials of sufficiently high mobility often evolves through three distinct stages, switching from compressive to tensile and back to compressive. Many studies of stress evolution during this process have indicated that a tensile st

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47

Hsieh, Tsung-Eong. "An investigation of grain boundary phase transitions at elevated temperatures by TEM." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/14565.

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48

Weinberg, Jonathan David 1966. "Geometrical and computational modelling of grain boundaries in aluminum." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/277888.

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This study presents an integrated approach using experimental high resolution electron microscopy, computer simulations and theoretical analysis, to provide a thorough atomic level investigation of grain boundaries. Examined here, are specific cases of pure aluminum grain boundaries. Energy calculations for the Sigma3 perfect twin, in a range of linear translational states, show that both the shape and location of the interfacial surface are important considerations.

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Arumugam, Selvi Agni. "Effect of Linear Direction Oscillation on Grain Refinement." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1388751708.

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Dogan, Omer Nihat. "Interactions between austenite grain boundaries and aluminum nitride precipitates." Case Western Reserve University School of Graduate Studies / OhioLINK, 1990. http://rave.ohiolink.edu/etdc/view?acc_num=case1054927506.

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