Dissertations / Theses on the topic 'Magnesium metal matrix nanocomposites'
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Pallikonda, Mahesh Kumar Pallikonda. "FORMING A METAL MATRIX NANOCOMPOSITE (MMNC) WITH FULLY DISPERSED AND DEAGGLOMERATED MULTIWALLED CARBON NANOTUBES (MWCNTs)." Cleveland State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=csu1503937490966191.
Full textMallmann, Camila. "Mechanisms of plastic deformation of magnesium matrix nanocomposites." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAI083/document.
Full textMagnesium is the lightest of all structural metals, which gives it a huge potential to be used in applications that require lightweighting. However, its strength needs to be increased in order to compete with other light metals such as aluminum and titanium. A solution is the reinforcement of magnesium and its alloys with the addition of oxide nanoparticles. The hexagonal close packed crystalline structure is responsible for the complex plasticity of magnesium, which is characterized by a very strong plastic anisotropy as well as a complex twinning activity. Understanding these deformation mechanisms is crucial for the development of more performant nanocomposites, allowing widespread industrial application. The present work focuses on the processing and characterization of magnesium based nanocomposites reinforced with oxide particles. Two different processing techniques have been compared: friction stir processing and ultrasound assisted casting. The homogeneity of the dispersion of the reinforcement particles has been verified in 2 and 3 dimensions using electron microscopy and X-ray tomography, respectively. Friction stir processing produces nanocomposites with a more homogeneous dispersion of particles, while reducing their size. Tensile tests have shown strengthening of magnesium with the addition of a volume fraction of only 0.3 % of reinforcement. An annealing heat treatment has then been performed in order to promote abnormal grain growth and single crystalline microcolumns for microcompression testing have been machined by focused ion beam (FIB). The purpose is to isolate the role of particles. The orientation dependent mechanism of deformation and the size effects have been studied in order to understand the influence of the reinforcement particles on the plasticity for orientations favorable for basal slip or tensile twinning. Differently from the strengthening observed macroscopically, no clear strengthening effect is observed on microcolumns when dislocation glide operates. The reason is the higher density of potentially mobile dislocations that is generated due to stress concentrations around the reinforcement particles. In addition, the size effects usually observed on pure magnesium have also been suppressed with the addition of particles. The reinforcement particles seem to affect the twin nucleation stress and twin morphology: particles induce the nucleation of multiple twins inside a microcolumn, whereas in pure magnesium, only one or two twins have been observed. These results provide relevant insights on the role of nanoparticles on the onset of plastic deformation, as well as size effect, in single crystalline magnesium nanocomposites
Shin, Dongho. "Microstructual Characteristics of Magnesium Metal Matrix Composites." Master's thesis, University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5494.
Full textID: 031001275; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Adviser: Yongho Sohn.; Title from PDF title page (viewed February 22, 2013).; Thesis (M.S.M.S.E.)--University of Central Florida, 2012.; Includes bibliographical references (p. 49-51).
M.S.M.S.E.
Masters
Materials Science Engineering
Engineering and Computer Science
Materials Science and Engineering
Kandemir, Sinan. "Semi-solid processing of metal matrix nanocomposites." Thesis, University of Leicester, 2013. http://hdl.handle.net/2381/28146.
Full textWilliams, J. R. "Corrosion of aluminium-copper-magnesium metal matrix composites." Thesis, University of Nottingham, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239852.
Full textHicks, Kevin Paul. "A study of magnesium and magnesium alloy composites containing alumina and silicon carbide-based fibres." Thesis, University of Bath, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359089.
Full textHa, H. U. "Squeeze casting of magnesium-based alloys and their metal matrix composites." Thesis, University of Southampton, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383410.
Full textWarwick, Cyril Marcus. "Microstructural and thermomechanical stability of fibrous metal matrix composites based on magnesium-lithium." Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.291604.
Full textVanderhout, Amy Ruth. "Synthesis and mechanical characterization of aligned carbon nanotube metal- and carbon-matrix nanocomposites." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/127095.
Full textCataloged from the official PDF of thesis.
Includes bibliographical references (pages 203-224).
Carbon nanotube (CNT) assemblies are seeing increasing use in engineering applications due to their advantaged, mass-specific physical properties. The high strength-to-weight ratio, electrical and thermal conductivity, and elastic properties make CNTs ideal for many aerospace, automotive, and electrical applications. In structural materials, CNTs are an outstanding candidate to provide nano-reinforcement, both in hybrid composites and nanocomposites, and they have been found to improve the hardness, yield strength, and conductivity of their matrix material. Additional enhancement of these matrices can be realized by using aligned CNTs (A-CNTs) of increased volume fraction, as explored in this work.
In this thesis, ceramic matrix nanocomposites (CMNCs), specifically A-CNT/carbon matrix nanocomposites (A/C-NCs), are synthesized by first infusing a carbon precursor resin into A-CNT arrays with CNT volume fractions (v[subscript f]) ranging from 1-30 vol%, and then pyrolyzing the resin to create a carbon matrix around the A-CNTs. Previous work with A/C-NC hardness suggests that such a lightweight, superhard material may rival the density-normalized hardness of diamond at high v[subscript f]. Various processes were refined and tested in this work, yielding microscale void-free A/CNCs up to 30% v[subscript f], with an ~7% improvement in hardness over baseline pyrolytic carbon (PyC) for 1% v[subscript f] A/C-NCs and <10% improvement in hardness for 5% v[subscript f] A-CNTs. A reinfusion (i.e. an initial infusion/pyrolysis cycle with three additional reinfusion/pyrolysis cycles) procedure was developed and implemented, and testing is recommended as immediate future work.
Although hardness determination of these reinfused samples is left for future work, the X-ray CT images of the final A/C-NCs after the fourth infusion show excellent infusion and few voids, suggesting that high hardness will be achieved. This thesis also explores and develops synthesis techniques for metal matrix nanocomposites (MMNCs), focusing on an aluminum matrix. As the surface energy of ACNTs is not conducive to wetting by Al (and many other metals), this surface energy must first be altered to allow Al matrix infusion for consistent composite fabrication. TiO₂ is conformally decorated onto ~100 [mu]m-tall A-CNT arrays via atomic layer deposition (ALD). A reduction process for the TiO₂ coating was developed, and a reduction to TiH₂ was determined to be promising, as the TiH₂ will not oxidize prior to Al infusion but can easily be reduced in a vacuum oven apparatus designed specifically to meet the needs of Al infusion.
Towards MMNCs, both solder and aluminum matrices are infused into the TiO₂-decorated A-CNTs. The solder experiments yielded mixed success, as the results suggest that both the reduction and the vacuum infusion steps are important factors determining successful wetting. Although Al infusion into an A-CNT array was unsuccessful without a dedicated Al infusion apparatus, molten Al was found to wet Ti well, which suggests that the Ti coating may allow for successful A-CNT wetting. Additional recommendations are provided to further refine the A/Al-NC fabrication process to improve Al infusion.
by Amy Ruth Vanderhout.
S.M.
S.M. Massachusetts Institute of Technology, Department of Aeronautics and Astronautics
Dongare, Vishal S. "Hot Extrusion of Carbon Nanotube - Magnesium Matrix Composite Wire." Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1415975904.
Full textYang, Xinliang. "Particle dispersion in aluminium and magnesium alloys." Thesis, Brunel University, 2016. http://bura.brunel.ac.uk/handle/2438/14437.
Full textMohamed, Othman [Verfasser], and Lothar [Akademischer Betreuer] Wagner. "Synthesis and characterization of Al6061/Al2O3 metal matrix nanocomposites fabricated by stir-casting / Othman Ahmed Othman Mohamed ; Betreuer: Lothar Wagner." Clausthal-Zellerfeld : Technische Universität Clausthal, 2019. http://d-nb.info/1231363193/34.
Full textNegroni, Matteo. "Studio e sviluppo di tecniche per la produzione di nanocompositi a matrice di alluminio." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amslaurea.unibo.it/4949/.
Full textSibanyoni, Johannes Mlandu. "Nanostructured light weight hydrogen storage materials." University of the Western Cape, 2012. http://hdl.handle.net/11394/4631.
Full textThe main objective of this study was to advance kinetic performances of formation and decomposition of magnesium hydride by design strategies which include high energy ball milling in hydrogen (HRBM), in combination with the introduction of catalytic/dopant additives. In this regard, the transformation of Mg → MgH2 by high energy reactive ball milling in hydrogen atmosphere (HRBM) of Mg with various additives to yield nanostructured composite hydrogen storage materials was studied using in situ pressure-temperature monitoring that allowed to get time-resolved results about hydrogenation behaviour during HRBM. The as-prepared and re-hydrogenated nanocomposites were characterized using XRD, high-resolution SEM and TEM, as well as measurements of the mean particle size. Dehydrogenation performances of the nanocomposites were studied by DSC / TGA and TDS; and the re-hydrogenation behaviour was investigated using Sieverts volumetric technique.
Ponthieu, Marine. "Nouveaux matériaux riches en Mg pour le stockage d’hydrogène : composés Mg6Pd1-xMTx (MT = Ni, Ag, Cu) massifs et nanoconfinés et nanocomposites MgH2-TiH2." Thesis, Paris Est, 2013. http://www.theses.fr/2013PEST1139/document.
Full textThis thesis is dedicated to the study of novel magnesium-rich compounds for solid state hydrogen storage. The aim is to destabilize Mg hydride and accelerate its sorption kinetics by alloying and nanostructuration. The first family of compounds concerns the Mg6Pd1-xTMx (TM = Ni, Ag, Cu) pseudo-binary phases. Their structural properties and the effects of Pd substitution have been studied by X-ray diffraction, scanning electron microscopy and electron microprobe analyses. Their thermodynamics and kinetics of hydrogenation have been determined by solid-gas reaction. Different hydrogenation mechanisms take place depending on the substituting element. The stability of the metal-hydrogen system is altered by the nature of the phases formed during hydrogenation reaction. Thus, metal to hydride transformation is characterized by at least two absorption plateau pressures. The pressure of the first plateau is similar to that of Mg/MgH2 while the second one occurs at higher pressure. The enthalpy and entropy of reaction are determined to quantify the destabilizing effect of Pd by TM substitution. Best desorption kinetics are found for the Ni containing alloy thanks to the catalytic effect of the Mg2NiH4 phase formed on hydrogenation. The second approach aims to combine alloying with nanostructuration effects. Nanoparticles of Mg6Pd as small as 3 nm are confined into nanoporous carbon matrix. By comparing their hydrogenation properties with those of the bulk alloy, we demonstrate that not only the (de)hydrogenation kinetics are much faster for the nanoparticles, but also that their hydrided state is destabilized. Finally, MgH2-TiH2 nanocomposites were synthesized by mechanical milling under reactive atmosphere. The addition of a catalyst (TiH2) and Mg nanostructuration allow strongly accelerating the sorption kinetics of hydrogen in Mg. To understand the role of the TiH2 phase on the outstanding kinetics of these nanocomposites, their structural properties have been determined by X-ray and neutron diffraction. The existence of a coherent interface between Mg and TiH2 phases is of major importance to facilitate H-mobility within the nanocomposite. Furthermore, it is shown that the TiH2 inclusions inhibit the Mg/MgH2 grain growth, thus maintaining the composites nanostructure during their cycling
Godbole, Chinmay. "The Influence of Reinforcement on Microstructure, Hardness, Tensile Deformation, Cyclic Fatigue and Final Fracture behavior of two Magnesium Alloys." University of Akron / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=akron1321633235.
Full textKhan, Kirity Bhusan. "Processing And Characterization Of B4C Particle Reinforced Al-5%Mg Alloy Matrix Composites." Thesis, Indian Institute of Science, 2000. http://hdl.handle.net/2005/182.
Full textRamunno, Monica V. "Preparation and Characterization of Spinel-based Interpenetrating Phase Composites via Transformation of 3-D Printed Precursor Shapes." Youngstown State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1472555655.
Full textOportus, Juan A. "Mechanical testing of magnesium matrix nanocomposites fabricated by ultrasonic dispersion method." 2007. http://catalog.hathitrust.org/api/volumes/oclc/177208850.html.
Full textTypescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 60-62).
Chou, Ming-Chun, and 周鳴群. "Effect of Magnesium on the Aging Behavior of Al-Zn-Mg/Al2O3 Metal Matrix Composites." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/99640953449158819803.
Full text國立交通大學
材料科學(工程)研究所
82
The effect of adding magnesium on the aging behavior of Al-Zn- Mg alloy reinforced with aluminum (Al2O3) was studied using differential scanning calorimeter(DSC) technique, hardness measurement. The magnesium contents were varied from 1.23wt% to 2.97wt%. The addition of magnesium was found to increase the amount of η'-phase formation in composites. The formation enthalpy of composites was 0.932cal/g and 1.375cal/g for lower magne- sium content(1.23wt%) and higher magnesium content(2.97 wt%) respectively. The time needed for the saturation of precipiat- ing in the composites changed from 12 hr to 48hr as the magne- sium content increased from 1.23wt% to 2.97wt%. The maximum hardness occurred in composites with 2.97wt% Mg that contained a maximum amounts of η'-phase precipitates. The hardness of the composites was always less than that of monoli- thic alloys because of alumina fibers caused suppression of η' formation in composites. Difference of wearability between composites and Al-Zn-Mg alloy was also performed in this study. The weight loss decreased with increasing the volume fraction of alumina and with increasing the magnesium content.
"Formation of an Mg-based metal matrix composite by the displacement reaction sintering between Mg and Ag2O powders." 2004. http://library.cuhk.edu.hk/record=b5896217.
Full textThesis (M.Phil.)--Chinese University of Hong Kong, 2004.
Includes bibliographical references.
Text in English; abstracts in English and Chinese.
Choi Ching-Yeung = Mei he yang hua yin fen fan ying zhi bei mei ji fu he cai liao / Cai Jingyang.
Abstract --- p.i
摘要 --- p.iii
Acknowledgement --- p.iv
List of Figures --- p.xi
List of Tables --- p.xvi
Chapter Chapter 1 --- Introduction --- p.1.1
Chapter 1.1 --- Metal matrix composites (MMCs) --- p.1.1
Chapter 1.1.1 --- Introduction --- p.1.1
Chapter 1.1.2 --- Reinforcement in metal-matrix composites --- p.1.1
Chapter 1.1.2.1 --- Particle-reinforced composites --- p.1.2
Chapter 1.1.2.2 --- Laminated composites --- p.1.2
Chapter 1.1.2.3 --- Fibre-reinforced composites --- p.1.2
Chapter 1.1.3 --- Conventional fabrication of metal matrix composites --- p.1.6
Chapter 1.1.3.1 --- Liquid state processes --- p.1.6
Chapter 1.1.3.1.1 --- Liquid infiltration --- p.1.6
Chapter 1.1.3.1.2 --- Pressure infiltration --- p.1.8
Chapter 1.1.3.1.3 --- Spray forming --- p.1.10
Chapter 1.1.3.2 --- Solid-state process --- p.1.11
Chapter 1.1.3.2.1 --- Powder consolidation --- p.1.11
Chapter 1.1.3.2.2 --- Diffusion bonding --- p.1.11
Chapter 1.1.3.2.3 --- In-Situ processes --- p.1.13
Chapter 1.1.4 --- Properties of metal matrix composites --- p.1.13
Chapter 1.2 --- Magnesium based metal matrix composites --- p.1.14
Chapter 1.2.1 --- Properties of Mg-based metal matrix composites --- p.1.14
Chapter 1.2.2 --- Application of Mg-based metal matrix composites --- p.1.16
Chapter 1.3 --- Magnesium and silver (I) oxide --- p.1.16
Chapter 1.3.1 --- Magnesium --- p.1.16
Chapter 1.3.2 --- Silver (I) oxide --- p.1.17
Chapter 1.4 --- Pervious works --- p.1.17
Chapter 1.5 --- Aims of Current works --- p.1.18
Chapter 1.6 --- Thesis layout --- p.1.20
References --- p.1.21
Chapter Chapter 2 --- Methodology and fabrication --- p.2.1
Chapter 2.1 --- Introduction --- p.2.1
Chapter 2.1.1 --- Powder metallurgy --- p.2.1
Chapter 2.1.1.1 --- Powder production --- p.2.3
Chapter 2.1.1.2 --- Powder consolidation --- p.2.4
Chapter 2.1.1.3 --- Sintering process --- p.2.6
Chapter 2.1.1.4 --- Properties of sintered parts --- p.2.10
Chapter 2.2 --- Sample preparation --- p.2.12
Chapter 2.3 --- Characterization methods --- p.2.13
Chapter 2.3.1 --- Thermal analysis - Differential Thermal Analysis (DTA) --- p.2.13
Chapter 2.3.2 --- Phase determination - X-ray Powder Diffractometry (XRD) --- p.2.13
Chapter 2.3.3 --- Microstructure analysis --- p.2.14
Chapter 2.3.3.1 --- Scanning electron microscopy (SEM) --- p.2.14
Chapter 2.3.3.1 --- Transmission electron microscopy (TEM and HRTEM) --- p.2.14
Chapter 2.3.4 --- Physical property - Thermomechanic analyser (TMA) --- p.2.14
Chapter 2.3.5 --- Mechanical property - Vickers hardness measurement --- p.2.15
References --- p.2.16
Chapter Chapter 3 --- Thermal analysis of Mg-Ag20 --- p.3.1
Chapter 3.1 --- Introduction --- p.3.1
Chapter 3.2 --- Experiments --- p.3.2
Chapter 3.3 --- Results --- p.3.2
Chapter 3.3.1 --- DTA curve of the Mg-30wt%Ag20 --- p.3.5
Chapter 3.3.2 --- DTA curve of the pure Ag20 powder --- p.3.7
Chapter 3.4 --- Discussions --- p.3.7
Chapter 3.5 --- Conclusions --- p.3.10
References --- p.3.11
Chapter Chapter 4 --- Fabrication and characterization of Mg-£-AgMg3 MMCs --- p.4.1
Chapter 4.1 --- Introduction --- p.4.1
Chapter 4.2 --- Experiments --- p.4.2
Chapter 4.2.1 --- Sample preparation --- p.4.2
Chapter 4.2.1.1 --- Effect of temperature --- p.4.2
Chapter 4.2.1.2 --- Effect of time --- p.4.3
Chapter 4.2.1.3 --- Effect of composition --- p.4.3
Chapter 4.2.1.4 --- Effect of cooling rate --- p.4.3
Chapter 4.3 --- Results --- p.4.4
Chapter 4.3.1 --- Samples sintered at different temperatures --- p.4.4
Chapter 4.3.1.1 --- XRD spectra --- p.4.4
Chapter 4.3.1.2 --- SEM micrographs and EDS analysis --- p.4.7
Chapter 4.3.1.3 --- Discussions --- p.4.11
Chapter 4.3.2 --- Sample with different dwelling times --- p.4.13
Chapter 4.3.2.1 --- SEM micrographs --- p.4.13
Chapter 4.3.2.2 --- Weight loss against dwelling time --- p.4.16
Chapter 4.3.2.3 --- Discussions --- p.4.18
Chapter 4.3.3 --- Samples with varied weight percentage of Ag2O --- p.4.19
Chapter 4.3.3.1 --- SEM micrographs --- p.4.19
Chapter 4.3.3.2 --- Discussions --- p.4.22
Chapter 4.3.4 --- Samples with different cooling rate --- p.4.23
Chapter 4.3.4.1 --- XRD patterns --- p.4.23
Chapter 4.3.4.2 --- Optical photographs --- p.4.25
Chapter 4.3.4.3 --- SEM micrographs --- p.4.28
Chapter 4.3.4.4 --- TEM micrographs and high-resolution TEM micrographs…… --- p.4.31
Chapter 4.3.4.5 --- Discussions --- p.4.35
Chapter 4.3.4.5.1 --- XRD spectra --- p.4.35
Chapter 4.3.4.5.2 --- Optical photographs --- p.4.35
Chapter 4.3.4.5.3 --- SEM micrographs --- p.4.35
Chapter 4.3.4.5.4 --- TEM micrographs --- p.4.36
Chapter 4.4 --- Conclusions --- p.4.37
References --- p.4.38
Chapter Chapter 5 --- Mechanical hardness and thermal expansion of Mg-Ag20 --- p.5.1
Chapter 5.1 --- Introduction --- p.5.1
Chapter 5.2 --- Mechanical properties --- p.5.1
Chapter 5.2.1 --- Experiments --- p.5.1
Chapter 5.2.2 --- Results --- p.5.2
Chapter 5.2.3 --- Discussions --- p.5.8
Chapter 5.3 --- Thermal properties --- p.5.9
Chapter 5.3.1 --- Experimental details --- p.5.9
Chapter 5.3.2 --- Results --- p.5.10
Chapter 5.3.3 --- Discussions --- p.5.12
Chapter 5.4 --- Conclusions --- p.5.13
References --- p.5.14
Chapter Chapter 6 --- Conclusions and future works --- p.6.1
Chapter 6.1 --- Conclusions --- p.6.1
Chapter 6.2 --- Further works --- p.6.2
Huang, Yusan, and 黃友聖. "AZ61/SiCp magnesium metal matrix composites extrusion process and the mechanical properties of the extrusion-tube." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/64987716617972401757.
Full text國立中正大學
機械工程學系暨研究所
99
The mechanical characteristics of magnesium metal matrix composites (Mg MMCs) are superior to those of the pure metal alloy; Adding the reinforcement, such as particles, shot fibers, and continuous fibers, to the metal matrix can improve the composite’s mechanical properties. SiCP is dissolved into AZ61 by the stir-casting method, and then the Mg-based composite is fabricated. The Mg-based composites are extruded under the conditions of 300oC and 400oC and the material plastic flow inside the die is analyzed with the finite element simulations. After extrusion, solid solution treatment of the products are conducted to improve their mechanical properties. Eventually, the mechanical properties of the composite before and after the extrusion with aging treatment are discussed. From the experimental results, it is known that the yielding strength and hardness of AZ61-Billet are 58MPa and 55.94HV, respectively. The yielding strength and hardness were improved by 7.4% and 5.4%, respectively, for 5wt%SiCp Billet. The yielding strength and hardness of AZ61-tube are 129MPa and 63.9HV, respectively, under extrusion temperature of 400oC, and its yielding strength and hardness are improved by 9.3% and 3.1%, respectively, after adding 5wt%SiCp; whereas, 10.9% and 8.9% increases are obtained under extrusion temperature of 300oC. After T5 aging treatment, the yielding strength and hardness of AZ61-tube are further increased by 10.1% and 8.3% under extrusion temperature of 400oC; and 12.4% and 18.4% with 300oC. With extrusion temperature of 400oC and T5 aging treatment, the ultimate strength obtained is 315MPa, the yielding strength is 145MPa, the ductility is 15.6%, and the hardness is 75.63HV.
"Fabrication and characterization of magnesium-based metal matrix composites =: 鎂金屬基複合材料的製備與性能測試." 2002. http://library.cuhk.edu.hk/record=b5891277.
Full textThesis (M.Phil.)--Chinese University of Hong Kong, 2002.
Includes bibliographical references.
Text in English; abstracts in English and Chinese.
by Man-Ling Wong.
Acknowledgments --- p.i
Abstract --- p.ii
摘要 --- p.iv
Table of contents --- p.v
Chapter Chapter 1 --- Introduction --- p.1-1
Chapter 1.1 --- Overview of metal matrix composites --- p.1 -1
Chapter 1.1.1 --- Types of MMCs --- p.1-1
Chapter 1.1.2 --- The matrices --- p.1 -2
Chapter 1.1.2.1 --- Mg-based matrix --- p.1 -2
Chapter 1.1.2.2 --- Al-based matrix --- p.1-2
Chapter 1.1.2.3 --- Ti-based matrix --- p.1 -3
Chapter 1.2 --- Fabrication methods of MMCs --- p.1 -3
Chapter 1.2.1 --- Solid-liquid reaction --- p.1-4
Chapter 1.2.2 --- Vapor-liquid-solid (VLS) reaction --- p.1 -4
Chapter 1.2.3 --- Solid-Solid reaction --- p.1-5
Chapter 1.2.4 --- Liquid-liquid reaction --- p.1-5
Chapter 1.3 --- Applications of MMCs --- p.1 -6
Chapter 1.4 --- Previous works versus our work --- p.1 -7
Chapter 1.5 --- Layout of the thesis --- p.1 -8
Figures --- p.1-9
References --- p.1-10
Chapter Chapter 2 --- Methodology and Instrumentation --- p.2-1
Chapter 2.1 --- Introduction --- p.2-1
Chapter 2.2 --- Powder metallurgy --- p.2-1
Chapter 2.3 --- Sample preparation --- p.2-2
Chapter 2.3.1 --- Cold pressing --- p.2-2
Chapter 2.3.2 --- Sintering --- p.2-3
Chapter 2.4 --- Characterization methods --- p.2-4
Chapter 2.4.1 --- Differential Thermal Analyzer (DTA) for thermal analysis --- p.2-4
Chapter 2.4.2 --- X-Ray powder Diffractometry (XRD) for phase determination --- p.2-5
Chapter 2.4.3 --- Scanning Electron Microscopy (SEM) and Electron Dispersive X-ray analysis (EDX) for structural analysis --- p.2-6
Chapter 2.4.4 --- Mechanical properties --- p.2-7
Chapter 2.4.4.1 --- Relative density --- p.2-7
Chapter 2.4.4.2 --- Porosity --- p.2-9
Chapter 2.4.4.3 --- Tensile strength --- p.2-10
Chapter 2.4.4.4 --- Hardness test --- p.2-10
Figures --- p.2-12
References --- p.2-18
Chapter Chapter 3 --- Formation of the Mg-ZnO MMCs --- p.3-1
Chapter 3.1 --- Thermal analysis on the reactions between Mg and ZnO --- p.3-1
Chapter 3.1.1 --- Introduction --- p.3-1
Chapter 3.1.2 --- Experiments --- p.3-1
Chapter 3.1.3 --- Results and Discussions --- p.3-1
Chapter 3.2 --- Characterization of the Mg-ZnO MMCs --- p.3-2
Chapter 3.2.1 --- Introduction --- p.3-2
Chapter 3.2.2 --- Experiments --- p.3-3
Chapter 3.2.3 --- Results and Discussions --- p.3-3
Chapter 3.2.3.1 --- Scanning electron microscopy (SEM) and Electron dispersive X-ray analysis (EDX) --- p.3-3
Chapter 3.2.3.2 --- X-ray Diffraction (XRD) --- p.3-4
Chapter 3.2.3.3 --- Mg-Zn intermetallics Phases --- p.3-5
Chapter 3.2.4 --- Model of formation of Mg-ZnO MMCs --- p.3-5
Chapter 3.2.4.1 --- Chemical reactions --- p.3-5
Chapter 3.2.4.2. --- Order of priority of reactions --- p.3-6
Chapter 3.2.4.3 --- Diffusion during sintering --- p.3-7
Chapter 3.2.4.4 --- Reaction Model --- p.3-8
Chapter 3.2.5 --- Conclusions --- p.3-8
Figures --- p.3-10
References --- p.3-18
Chapter Chapter 4 --- Mechanical properties of the Mg-ZnO MMCs --- p.4-1
Chapter 4.1 --- Introduction --- p.4-1
Chapter 4.2 --- Experiments --- p.4-1
Chapter 4.3 --- Results and Discussions --- p.4-2
Chapter 4.3.1 --- Relative density --- p.4-2
Chapter 4.3.2 --- Porosity --- p.4-3
Chapter 4.3.3 --- Tensile strength --- p.4-4
Chapter 4.3.4 --- Hardness --- p.4-6
Chapter 4.4 --- Conclusions --- p.4-7
Figures --- p.4-9
References --- p.4-23
Chapter Chapter 5 --- Reinforcement in Mg-ZnO MMCs --- p.5-1
Chapter 5.1 --- Introduction --- p.5-1
Chapter 5.2 --- Experiments --- p.5-1
Chapter 5.3 --- Results and Discussions --- p.5-1
Chapter 5.3.1 --- Microstructure of the Mg-ZnO MMCs --- p.5-2
Chapter 5.3.2 --- Fracture of Mg-ZnO MMCs --- p.5-5
Chapter 5.3.2.1 --- Fracture surface --- p.5-5
Chapter 5.3.2.2 --- Fracture mode --- p.5-7
Chapter 5.4 --- Conclusions --- p.5-8
Figures --- p.5-9
References --- p.5-18
Chapter Chapter 6 --- Conclusions and Future Works --- p.6-1
Chapter 6.1 --- Conclusions --- p.6-1
Chapter 6.2 --- Future Works --- p.6-2
References --- p.6-4
Ali, Addisu Negash, and Addisu Negash Ali. "Structural Integrity Assessment of SiCp/AZ61 Magnesium Alloy Metal Matrix Composites Processed by Heat Treatment and Severe Plastic Deformation." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/y5a42b.
Full text國立臺灣科技大學
機械工程系
107
In this work, heat treatment (homogenization and ageing heat treatment processes) and extrusion plus A route type equal channel angular pressing (ECAP) severe plastic deformation methods were used to improve the microstructural and mechanical properties of as-cast SiCp/AZ61 magnesium metal matrix composites (Mg MMCs) fabricated by stir casting method. Different weight percentages (0%, 2% and 5%) of SiC particles (SiCp) were considered to study the effects of contents of reinforcements at different treatment conditions. Microstructural changes due to heat treatment processes, the number of ECAP passes and SiCp weight percentages were assessed using optical microscope (OM), scanning electron microscope (SEM), microhardness test and X-ray diffraction (XRD) patterns analysis. Enhanced mechanical properties were analyzed based on the Charpy impact and the uniaxial tensile test data. Furthermore, the brittle-ductile properties were testified by using scanning electron microscopy (SEM) features of Charpy impact and tensile test fracture surfaces. The work-hardening behavior of AZ61 magnesium alloy and SiCp/AZ61 Mg MMCs deformed by ECAP plastic deformation were studied by considering strain hardening rate (θ). The details of plastic deformation mechanisms and plastic deformation stages were identified by using a Crussard-Jaoul method based on the Ludwik equation. The response surface methodology in the design of experiments (DOE) wizard and Gurson-Tvergaard-Needleman (GTN) model were employed to estimate the optimum GTN damage parameters and to validate their significant effects respectively on the ductile fracture behavior of ECAP deformed AZ61 magnesium alloy. Hollomon flow stress was applied to identify uniform deformation and non-uniform deformation regions to investigate the void nucleation and coalescence processes separately. From the results obtained, ageing heat treatment process was seen significant on the 12 h aged 2 wt% SiCp/AZ61 Mg MMC which induced lower microhardness values and results in the formations of particle free regions and discontinuous secondary phases. At a higher number of ECAP passes and higher SiCp weight percentage, higher elastic modulus was seen enhanced. The strength, ductility and work-hardening behaviors were varied for both ECAP plastic deformation and SiCp weight percentage variations. The results of ductile fracture behavior of ECAP deformed AZ61 magnesium alloy showed that varying both stress triaxiality and damage variables simultaneously can greatly affect the curve fitting process of experimental, simulation and GTN model curves. The main contribution of this research work is enhancing the mechanical properties of SiCp/AZ61 Mg MMCs by modifying the presence and amount of microstructural constituent phases and by improving their uniform distribution.
Sudarshan, *. "Magnesium Matrix-Nano Ceramic Composites By In-situ Pyrolysis Of Organic Precursors In A Liquid Melt." Thesis, 2010. http://etd.iisc.ernet.in/handle/2005/2066.
Full textAghachi, Izendu Emenike Alu. "Dynamic stress analysis of composite structures under elastic wave load : particulate reinforced metal matrix composites." 2012. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1000194.
Full textDiscusses the main objective of this study was to extend the hybrid method developed by Paskaramoorthy, et al (1988). This objective was to study the effect of elastic wave on any particulate reinforced metal matrix composite (PRMMC). The specific objectives were: to compare the effect of plane wave and shear vertical wave on a particular particulate reinforced metal matrix composite (PRMMC)-Mg/TiC, using analytical method ; to use the extended hybrid method to determine the effect of particle size and single interface layer on Mg/TiC.
Hsieh, Cheng-Han, and 謝承翰. "Hydrothermal growth of hydroxyapatite film on the surface of magnesium alloy (AZ31) based metal matrix compsite containing hydroxyapatite powder produced by friction stir processing." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/77292092080724628084.
Full text國立中山大學
材料與光電科學學系研究所
104
The friction stir process was employed to make a composite magnesium alloy AZ31B containing hydroxyapatite. Followed by hydrothermal method, hydroxyapatite (HA) film was deposited onto the sample surface. Hydrothermal reagents are composed of 0.25mol / M of Ca-EDTA and KH2PO4, and sodium hydroxide as a buffer to maintain the pH of the solution at 8.9 and the temperature controlled at 90 ° C. Magnesium in the surface would have replacement reaction with the solution in the system with the time of 3,6,12 hours. A Scanning Electron Microscope (SEM) was used to examine the specimen surface morphology and composition variations X-ray Energy Dispersive Spectrometer (EDS) and back-scattered electron imaging (BEI). Experimental results showed a bonding layer with thickness about 100 nm exists between the substrate and the coating. The bonding layer would become joining surface for substrate and Hap. The earlier forming of coating is probably calcium deficient hydroxyapatite (CDHA) , and the top of coating is probably hydroxyapatite (HA). The chemical solution also brings demineralization to form some vertical cracks. Keywords: hydroxyapatite , calcium deficient hydroxyapatite, friction stir process, coating technology , cracks, hydrothermal method , bonding layer.
"Growth of nanorods or nanostructured eutectic in the formation of Mg-based metal matrix composities: 納米棒或納米結構共晶在鎂金屬基複合材料製備時的生長過程." 2003. http://library.cuhk.edu.hk/record=b6073600.
Full text"October 2003."
Thesis (Ph.D.)--Chinese University of Hong Kong, 2003.
Includes bibliographical references.
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Mode of access: World Wide Web.
Abstracts in English and Chinese.
Nan Gang Ma.