Dissertations / Theses on the topic 'Metal composite materials'
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Ellerby, Donald Thomas. "Processing and mechanical properties of metal-ceramic composites with controlled microstructure formed by reactive metal penetration /." Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/10583.
Full textWard, William F. "A theoretical investigation into the inelastic behavior of metal-matrix composites." Thesis, Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/17244.
Full textChoi, Yuk-ning Alta. "Repair technology for cracked metallic structures using composite materials /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21213239.
Full textMokhtari, Morgane. "FeCr composites : from metal/metal to metal/polymer via micro/nano metallic foam, exploitation of liquid metal dealloying process." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEI088/document.
Full textNanoporous metals have attracted considerable attention for their excellent functional properties. The first developed technique used to prepare such nanoporous noble metals is dealloying in aqueous solution. Porous structures with less noble metals such as Ti or Fe are highly desired for various applications including energy-harvesting devices. The less noble metals, unstable in aqueous solution, are oxidized immediately when they contact water at a given potential so aqueous dealloying is only possible for noble metals. To overcome this limitation, a new dealloying method using a metallic melt instead of aqueous solution was developed. Liquid metal dealloying is a selective dissolution phenomenon of a mono-phase alloy solid precursor: one component (referred as soluble component) being soluble in the metallic melt while the other (referred as targeted component) is not. When the solid precursor contacts the metallic melt, only atoms of the soluble component dissolve into the melt inducing a spontaneously organized bi-continuous structure (targeted+sacrificial phases), at a microstructure level. This sacrificial phase can finally be removed by chemical etching to obtain the final nanoporous materials. Because this is a water-free process, it has enabled the preparation of nanoporous structures in less noble metals such as Ti, Si, Fe, Nb, Co and Cr. The objectives of this study are the fabrication and the microstructure and mechanical characterization of 3 different types of materials by dealloying process : (i) metal/metal composites (FeCr-Mg), (ii) porous metal (FeCr) (iii) metal/polymer composites (FeCr-epoxy resin). The last objective is the evaluation of the possibilities to apply liquid metal dealloying in an industrial context. The microstructure study was based on 3D observation by X-ray tomography and 2D analysis with electron microscopy (SEM, SEM-EDX, SEM-EBSD). To have a better understanding of the dealloying, the process was followed in situ by X-ray tomography and X-ray diffraction. Finally the mechanical properties were evaluated by nanoindentation and compression
Breunig, Thomas M. "Nondestructive evaluation of damage in SiC/Al metal matrix composite using x-ray tomographic microscopy." Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/19999.
Full text蔡玉寧 and Yuk-ning Alta Choi. "Repair technology for cracked metallic structures using composite materials." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31222420.
Full textKelly, Aoife. "Processing of bulk hierarchical metal-metal composites." Thesis, University of Oxford, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.559831.
Full textDrury, William James. "Quantitative microstructural and fractographic characterization of AE-Li/FP metal matrix composite." Thesis, Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/19958.
Full textKabche, Jean Paul. "Structural Testing and Analysis of Hybrrid Composite/Metal Joints for High-Speed Marine Structures." Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/kabchejp2006.pdf.
Full textKo, Ying-hsiang. "The growth of metal particles in porous glass and the dielectric and optical properties of the composites /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487267024996737.
Full textPRADO, JOHN STEVEN CASTELLANOS. "ANALYSIS PIPELINE COMPONENTS WITH METAL LOSS REPAIRED WITH COMPOSITE MATERIALS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2014. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=24562@1.
Full textPROGRAMA DE EXCELENCIA ACADEMICA
Neste trabalho foram estudados quatro geometrias de componentes tubulares, para trabalho sob pressão interna, que continham defeitos tipo perda de espessura metálica em regiões de sua superfície externa e que foram reparados por dois sistemas de materiais compósitos. As seguintes geometrias de espécimes tubulares foram estudadas: dutos com redução de diâmetro, dutos curvados a frio, dutos curvados a quente e uniões tubulares em T. Os dois sistemas de materiais compósitos consistiram de um sistema com mantas de resina epóxi reforçadas por fibra de vidro (ERFV) e outro sistema com mantas de resina epóxi reforçadas por fibra de carbono (ERFC). O método de Elementos Finitos foi usado para simular o comportamento dos espécimes quando submetidos a testes hidrostáticos. As simulações levaram em consideração o comportamento do material dos tubos API 5L Grau B nas suas regiões elástica e plástica, e investigaram o aumento da resistência à ruptura dos tubos com defeitos proporcionados pela presença dos reparos compósitos. Os resultados obtidos com os modelos de elementos finitos, usados para as determinações de distribuições de deformações e de pressões de ruptura, foram comparados com resultados experimentais disponíveis para cada componente tubular. Os resultados destas comparações foram satisfatórios. Posteriormente, foram desenvolvidas equações para determinar espessuras otimizadas para os reparos e os resultados obtidos com estas equações foram comparados com os resultados das simulações por elementos finitos e outros resultados obtidos com equações disponíveis em normas pertinentes. Em conclusão, o método de elementos finitos usado neste trabalho simulou satisfatoriamente o comportamento em testes hidrostáticos de componentes tubulares tipo Tê, com redução concêntrica, curvados a quente e curvados a frio, com defeitos de perda de espessura metálica e que foram reparados com materiais compósitos. Por sua vez, os resultados numéricos auxiliaram na validação de equações analíticas simples que poderão ser usadas na determinação de espessuras otimizadas de sistemas de reparos com materiais compósitos.
This dissertation investigates four geometries of pipe components that operate with internal pressure and contain metal loss defects in areas of their external surface. These components were repaired with two systems of composite materials that consisted of epoxy resin reinforced by glass fiber (ERFV) and epoxy resin reinforced by carbon fiber (ERFC). The following tubular specimens were studied: components with concentric diameter reducers, hot curved short radius elbow components, cold curved long radius elbow components and T-components. The finite element method was used to simulate the behavior of the specimens when submitted to hydrostatic tests. The simulations took into consideration the behavior of the material of the pipes API 5L Grade B in their elastic and plastic regions, and investigated the increase in the rupture strength of the pipes with defects that was provided by the presence of composite repairs. The results obtained with the finite element models, used for the determination of distributions of deformation and burst pressures, were compared with experimental results available for each pipe component. The results of these comparisons were satisfactory. Subsequently, simple analytical equations were developed to determine the optimized thicknesses for the composite repair systems and the results obtained from these equations were compared with the results determined with the finite element models and with other results obtained with equations recommended by international relevant standards. In conclusion, the finite element method used in this work satisfactorily simulated the behavior of the selected pipe components with defects of metal loss that were hydrostatically tested and that were repaired with composites materials. The numerical results helped to validate simple analytical equations that can be used in the determination of the optimized thicknesses of repair systems with composite materials.
Strossi, Pedrolo Débora Regina. "Synthesis of metal-zeolite composite materials for bifunctional catalytic reactions." Thesis, Université de Lille (2018-2021), 2021. https://pepite-depot.univ-lille.fr/LIBRE/EDSMRE/2021/2021LILUR065.pdf.
Full textZeolite-based catalysts have been widely used in the conversion of biomass. The catalytic yields of the desired products are strongly limited due to the relatively small size of the pores in zeolites and the catalyst preparation by impregnation usually leads to relatively large metal nanoparticles and low contact between metal and acid sites. The purpose of this work is the design of metal-zeolite nanocomposite catalysts containing ruthenium nanoparticles uniformly distributed in the hierarchical BEA and ZSM-5 zeolites. Use of ruthenium avoids formation of inert hardly reducible inert metal silicates and metal aluminates, while carbon nanotubes with supported metal oxide nanoparticles play a role of sacrificial template, which allows creating mesoporosity and bringing metallic functionality inside the zeolite matrix. Compared to the conventional zeolite supported metal catalysts the synthesized hierarchical ruthenium-zeolites exhibited much higher activity and lower methane selectivity in Fischer-Tropsch synthesis. Characterization of the prepared catalysts has indicated initiation of crystallization of zeolites over metal nanoparticles. This effect has been further used to increase the dispersion of metal nanoparticles by secondary crystallization of Ru supported over ZSM-5. Our results show significant re-dispersion of embedded metal oxide nanoparticles and increase in the activity of model reactions. In addition, a synthetic strategy was developed for the preparation of hierarchical metal and zeolite nanocomposite catalysts for direct synthesis of iso-paraffins from syngas. The nanocomposites are synthesized in three steps. In the first step, the parent (core) zeolite is etched with an ammonium fluoride solution. The etching creates small mesopores inside the zeolite crystals. In the second step, the Ru nanoparticles prepared using water-in-oil microemulsion are deposited in the mesopores of the zeolite. In the third step, a zeolite shell of MFI-type zeolites (silicalite-1 or ZSM-5) is grown on the parent zeolite crystals coating both the etched surface and metallic nanoparticles. Thus, the metal nanoparticles become entirely encapsulated inside the zeolite matrix. Most important parameters such as ruthenium content, zeolite mesoporosity, and more particularly, the acidity of the catalyst shell, which affect the catalytic performance of the synthesized nanocomposite materials in low-temperature Fischer−Tropsch synthesis were identified in this work. The higher relative amount of iso-paraffins was observed on the catalysts containing a shell of ZSM-5. The proximity between metal and acid sites in the zeolite shell of the nanocomposite catalysts is a crucial parameter for the design of efficient metal zeolite bifunctional catalysts for selective synthesis of gasoline-type fuels via Fischer−Tropsch synthesis, while the acidity of the catalyst core has only a limited impact on the catalytic performance
Noh, Tae Won. "Optical properties of some metal-insulator composites /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487266362336089.
Full textMiotti, Bettanini Alvise. "Welding of high performance metal matrix composite materials: the ICME approach." Thesis, KTH, Metallografi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-154021.
Full textKlopfer, Joseph E. "An experimental study of fiberglass composites containing metal wire joints." Thesis, Monterey, California : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Sep/09Sep%5FKlopfer.pdf.
Full textThesis Advisor(s): Kwon, Young W. "September 2009." Description based on title screen as viewed on 6 November 2009. Author(s) subject terms: Vacuum assisted resin transfer, VARTIM, composite, fiberglass, metal wire, metal composite, Mode I, ANSYS 12.0. Includes bibliographical references (p. 39). Also available in print.
Annamalai, Perushini. "Electrospinning of porous composite materials for hydrogen storage application." University of the Western Cape, 2016. http://hdl.handle.net/11394/5654.
Full textDue to the rapid depletion of fossil fuel reserves and the production of environmentally harmful by-products such as carbon dioxide, there is an urgent need for alternate sustainable clean energy. One of the leading candidates in this endeavour is hydrogen, which can be used as an energy carrier since it has a high energy density, zero emissions and is produced from non-depletable resources such as water. The major challenge hindering a hydrogen economy is the lack of safe and effective storage technologies for mobile applications. A prospective solution to this problem lies in the use of porous powdered materials, which adsorb the hydrogen gas. However, the integration of these powdered materials into a storage tank system, results in the pipelines being contaminated during filling cycles. This necessitates the shaping of the porous powdered materials. Among the many shaping techniques available, the electrospinning technique has been proposed as a promising technology since it is a versatile process that is easily scaled-up making it attractive for the applications of the study. Furthermore, the electrospinning process enables the synthesis of nano-sized fibres with attractive hydrogen sorption characteristics. In this regard, the current study employs the electrospinning technique to synthesise electrospun composite fibres for mobile hydrogen storage applications. After electrospinning three polymers, polyacrylonitrile (PAN) was selected as the most suitable polymer because it yielded bead-free electrospun fibres. However, the diameter of the PAN fibres was large/thick which prompted further optimisation of the electrospinning parameters. The optimised electrospinning conditions that yield unbeaded fibres within the desired diameter range (of 300-500 nm) were a PAN concentration of 10 wt%, a flow rate of 0.4 mL/h, a distance of 10 cm between the needle tip and collector plate, and an applied voltage of 8 kV. The study then progressed to the synthesis and characterisation of the pristine porous powdered materials which adsorb hydrogen gas. The porous powdered materials investigated were commercial zeolite 13X, its synthesised templated carbon derivative (ZTC) and Zr (UiO-66) and Cr (MIL-101) based metal-organic frameworks (MOFs). ZTC was synthesised via liquid impregnation coupled with chemical vapour deposition (CVD), and the MOFs were synthesised by the modulated solvothermal method. Analysis of the ZTCs morphology and phase crystallinity show that the carbon templated process using zeolites was successful, however, ZTC was amorphous compared to crystalline zeolite template. The BET surface area was assessed with the aid of nitrogen sorption isotherms for both zeolite 13X and ZTC, and values of 730 and 2717 m²/g, respectively were obtained. The hydrogen adsorption capacity for zeolite 13X was 1.6 wt% and increased to 2.4 wt% in the ZTC material at 77 K and 1 bar. The successful synthesis of well defined, crystalline MOFs was evident from X-ray diffraction and morphological analysis. The BET surface area and hydrogen adsorption for Zr MOF were 1186 m²/g and 1.5 wt%, respectively at 77 K and 1 bar. Cr MOF had a BET surface area of 2618 m²/g and hydrogen adsorption capacity of 1.9 wt% at 77 K and 1 bar. The main focus of the study was to synthesise electrospun composite fibres that can adsorb hydrogen gas and thus provide significant insight in this field of research. As such it examined composite fibres that incorporates porous powdered materials such as zeolite 13X, ZTCs, UiO-66 (Zr) MOF and MIL-101 (Cr) MOF and investigated their ability to adsorb hydrogen gas, which have not been reported previously. The synthesis of composite fibres was achieved by incorporating the porous powdered materials into the PAN resulting in a polymeric blend that was then electrospun. Morphological analysis illustrated that the porous powdered materials were successfully supported by or incorporated within the PAN fibres, forming composite fibres. The BET surface area of the 40 wt% zeolite-PAN and 12.5 wt% ZTC-PAN composite fibres were 440 and 1787 m²/g respectively. Zr MOF and Cr MOF composite fibres had a BET surface area of 815 and 1134 m²/g, respectively. The BET surface area had reduced by 40, 34, 31 and 57% for zeolite 13X, ZTC, Zr MOF and Cr MOF, respectively after these porous powdered materials were incorporated into PAN. The hydrogen adoption capacity for 40 wt% zeolite-PAN, 12.5 wt% ZTC-PAN, 20 wt% Zr MOFPAN and 20 wt% Cr MOF-PAN composite fibres was 0.8, 1.8, 0.9 and 1.1 wt%, respectively. This decrease was attributed to the limited amount of porous powdered materials that could be incorporated into the fibres since only 40 wt% of zeolite 13X, 12.5 wt% of ZTC and 20 wt% of the MOFs were loaded into their respective composite fibres. This was due to the fact that incorporation of greater amounts of porous powdered materials resulted in a viscous polymeric blend that was unable to be electrospun. It is evident from the study that electrospinning is a versatile process that is able to produce composite fibres with promising properties that can potentially advance the research in this field thus providing a practical solution to the problem of integrating loose powdered materials into an on-board hydrogen storage system.
CSIR Young Researchers Establishment Fund (YREF)
Osborne, Deborah J. "Experimental and computational study of interphase properties and mechanics in titanium metal matrix composites at elevated temperatures /." View online ; access limited to URI, 2007. http://0-digitalcommons.uri.edu.helin.uri.edu/dissertations/AAI3277003.
Full textAlbat, Andreas Michael. "Thermal residual stresses in bonded composite repairs on cracked metal structures." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0003/NQ34504.pdf.
Full textHenriques, Alexandra J. "Nano-Confined Metal Oxide in Carbon Nanotube Composite Electrodes for Lithium Ion Batteries." FIU Digital Commons, 2017. http://digitalcommons.fiu.edu/etd/3169.
Full textJonke, Alex P. "Atomic metal/polyaniline composites." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/49070.
Full textJoesbury, Adam Michael. "New approaches to composite metal joining." Thesis, Cranfield University, 2015. http://dspace.lib.cranfield.ac.uk/handle/1826/10009.
Full textGriffin, David. "Studies of and modelling of the fracture behaviour of composite materials." Thesis, Northumbria University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245214.
Full textStyles, Millicent. "Characterisation of the flexural behaviour of aluminium foam composite sandwich structures /." View thesis entry in Australian Digital Theses Program, 2008. http://thesis.anu.edu.au/public/adt-ANU20080813.170807/index.html.
Full textYüksel, Sinan Güden Mustafa. "Crushing behaviour of aluminum foam-filled composite tubes/." s.l.]: [s.n.], 2005. http://library.iyte.edu.tr/tezler/master/makinamuh/T000380.pdf.
Full textKeywords:crushing, aluminum foam, foam filling, energy absorber, composite tubes. Includes bibliographical references (leaves. 93-96).
Anyaogu, Kelechi C. "Stabilized metal nanoparticle-polymer composites preparation, characterization and potential applications /." Bowling Green, Ohio : Bowling Green State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=bgsu1222126708.
Full textDutta, Monojit. "Residual stress measurement in engineering materials and structures using neutron diffraction." Thesis, Open University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301945.
Full textEğilmez, Mehmet Özyüzer Lütfi. "Microstructural, electrical and mechanical properties of MgB2/Mg metal matrix composites/." [s.l.]: [s.n.], 2004. http://library.iyte.edu.tr/tezler/master/malzemebilimivemuh/T000467.pdf.
Full textAli, Mubarak. "How to predict the mechanical properties of a composite structure assembled with a metal structure." Thesis, Uppsala universitet, Tillämpad mekanik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-399690.
Full textSENE, FRANK F. "Resistividade eletrica de materiais compositos do tipo ceramica-metal na regiao de percolacao: aplicacao em cadinhos para fornos de inducao." reponame:Repositório Institucional do IPEN, 1997. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10657.
Full textMade available in DSpace on 2014-10-09T14:01:24Z (GMT). No. of bitstreams: 1 05241.pdf: 1844755 bytes, checksum: c891772effe3eef5424b2f166fa03521 (MD5)
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
Wickenheisser, Martin [Verfasser]. "Synthesis of metal-organic frameworks and monolithic composite materials for water sorption applications / Martin Wickenheisser." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2015. http://d-nb.info/107275584X/34.
Full textKatepalli, Nagababu Lankarani Hamid M. "Parametric study of stress concentration in bolted lap joints between particulate metal matrix composite materials." Diss., A link to this thesis in SOAR, 2006. http://soar.wichita.edu/dspace/handle/10057/660.
Full text"December 2006. Title from PDF title page (viewed on August 17, 2007). Thesis adviser: H.M. Lankarani. Includes bibliographic references (leaves 84-86).
Ferreira, Fabio Furlan. "Eletrocromismo em filmes finos compósitos." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-05072012-162751/.
Full textIn this work we initially calculated the optical properties of cermet films of Me-NiO and Me-CoO, being the metals Me = Au, Ag, Cu, Ni, Pd and Pt, by means of the Maxwell Garnett effective medium theory. This theoretical study allowed evaluating the viability to obtain, experimentally, a colored material in the visible spectrum region, with selective absorption in a narrow range of wavelengths. The results showed that the ideal candidate for such goal is the Au cermet. Looking at this result, the growth of Au-NiO and Au-CoO thin films was initiated using different experimental strategies: (i) deposition by reactive DC magnetron sputtering, (ii) deposition of the NiO, film by reactive DC magnetron sputtering and Au by the sol-gel and dip coating methods and (iii) deposition of both films, NiOxHy and Au, by sol-gel and dip coating. The films grown by sputtering showed a small selectivity (-5-10%), due to the atomistic character of this type of technique. It leads to the formation of small clusters of Au (smaller than -3 nrn), instead of aggregates with sizes of the order of some tenths of nanometers, easily obtained by the sol-gel method. Better selectivity, around 15%, is obtained in films deposited as multilayers. Post thermal annealing of the cermet films grown by sputtering induces the agglomeration of Au, but destroys the electrochromic properties. In the case of Au films grown by sol-gel, the spectral selectivity increases, due to the presence of Au, going from 15% to 20% in films deposited on the oxide matrix, deposited by sputtering and sol-gel, respectively. Under electrochemical processes, the NiOxHy films grown by sol-gel and dip coating presented the highest transmission variation (70%), due to larger porosity of these films.
Stults, Katrina A. "Metal-organic framework-metal oxide composites for toxic gas adsorption and sensing." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/51836.
Full textBykov, P. A., T. A. Chernysheva, and L. I. Kobeleva. "Surface layers by wear tests of particulate metal matrix composites." Thesis, Видавництво СумДУ, 2011. http://essuir.sumdu.edu.ua/handle/123456789/20526.
Full textFernandez, Mauricio. "Effects of Temperature and Creep on the Clamp-up Load in Hybrid Metal to Composite Bolted Joints." Fogler Library, University of Maine, 2008. http://www.library.umaine.edu/theses/pdf/FernandezM2008.pdf.
Full textAyanda, Olushola Sunday. "Adsorption of organotin compounds on nano metal oxide/silica, activated carbon and fly ash composite materials." Thesis, Cape Peninsula University of Technology, 2013. http://hdl.handle.net/20.500.11838/760.
Full textIn this present study, the physicochemical properties, nature and morphology of prepared composite materials involving activated carbon, fly ash, nFe3O4, nSiO2 and nZnO in the 1:1 ratio for two components composite materials and 1:1:1 for three components composite materials were investigated. The nature, morphology and elemental characterizations of these materials were carried out by means of modern analytical methods such as scanning electron and transmission electron microscopy (SEM and TEM), x-ray diffraction (XRD), x-ray fluorescence (XRF), inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled plasma atomic emission spectroscopy (ICP-AES) and Fourier transform infrared spectroscopy (FTIR). Other physicochemical characterizations undertaken were CNH analysis, ash content, pH, point of zero charge and surface area and porosity determination by Brunauer, Emmett and Teller (BET). The precursors and composite materials were then applied to the sorption (remediation) of tributyltin (TBT) and triphenyltin (TPT) from artificial seawater and wastewater and the adsorption efficiencies for the precursors and the composites compared. The adsorption of TBT and TPT onto these materials as a function of adsorbent amount, contact time, pH, stirring speed, initial adsorbate concentration and temperature was investigated. Maximum organotin adsorption was recorded within the pH range of normal saline water (pH 8). Approximately 99.95 %, 95.75 %, 96.78 %, 99.88 %, 96.96 %, 99.98 %, 99.99 %, 99.99 % and 99.99 % TBT were removed from 25 mL of 100 mg/L TBT-contaminated artificial seawater using 0.5 g adsorbents at a contact time of 60 min, pH 8, stirring speed 200 rpm and temperature of 80 oC by activated carbon, fly ash, nFe3O4, nSiO2, nZnO, fly ash/activated carbon, nFe3O4/activated carbon, nSiO2/activated carbon and nZnO/activated carbon composite, respectively and the adsorption of TBT onto these adsorbents was endothermic. Approx. 99.99 %, 96.54 %, 95.50 %, 96.92 %, 97.14 %, 99.99 %, 98.44 %, 98.98 % and 99.66 % TPT were also removed from 25 mL of 100 mg/L TPT-contaminated artificial seawater using 0.5 g adsorbents at a contact time of 60 min, pH 8, stirring speed 200 rpm and a temperature of 20 oC by the activated carbon, fly ash, nFe3O4, nSiO2, nZnO, fly ash/activated carbon, nFe3O4/fly ash, nSiO2/fly ash and nZnO/fly ash composite, respectively. The adsorption of TPT onto activated carbon and fly ash/activated carbon composite from TPT – contaminated artificial seawater was endothermic while TPT adsorption onto fly ash, nFe3O4, nSiO2, nZnO, nFe3O4/fly ash, nSiO2/fly ash and nZnO/fly ash composites from TPT – contaminated artificial seawater was exothermic. The adsorption of TBT and TPT onto nFe3O4/fly ash/activated carbon and nSiO2/fly ash/activated carbon composites from TBT – and TPT – contaminated water, respectively were endothermic and approx. 99.98 % and 99.99 % of TBT and TPT, respectively were removed from the initial concentration of 100 mg/L OTC by the composites at a temperature of 80 oC, 60 min contact time, pH 8 and a stirring speed of 200 rpm. The adsorption kinetics of all the precursors and composite materials fitted well with the pseudo second-order kinetic model while the adsorption isotherm data could be well described by the Freundlich isotherm model except TBT adsorption onto nZnO/activated carbon and nFe3O4/activated carbon composite from TBT contaminated artificial seawater, TPT adsorption onto activated carbon and fly ash/activated carbon from TPT contaminated artificial seawater, and TPT sorption onto nSiO2/fly ash/activated carbon composite from TPT – contaminated water which could be described by both the Freundlich and Dubinin-Radushkevich (D-R) isotherm models. Optimal conditions for the adsorption of TBT and TPT from artificial seawater were further applied to TBT and TPT removal from TBT – and TPT – contaminated natural seawater obtained from Cape Town harbour and the results obtained show that 99.71 %, 79.23 %, 80.11 %, 82.86 %, 80.42 %, 99.75 %, 99.88 %, 99.83 % and 99.88 % TBT were removed from TBT – contaminated natural seawater by activated carbon, fly ash, nFe3O4, nSiO2, nZnO, fly ash/activated carbon, nFe3O4/activated carbon, nSiO2/activated carbon and nZnO/activated carbon composite, respectively while 99.90 %, 96.44 %, 95.37 %, 96.75 %, 97.03 %, 99.92 %, 98.42 %, 98.92 % and 99.58 % TPT were removed from TPT – contaminated natural seawater by activated carbon, fly ash, nFe3O4, nSiO2, nZnO, fly ash/activated carbon, nFe3O4/fly ash, nSiO2/fly ash and nZnO/fly ash composite, respectively. Experimental results therefore show that the composite materials present higher organotin adsorption efficiency than the precursors due to the nature and improved properties of the composite materials and can therefore be utilized for the remediation of organotin contamination from industrial and/or shipyards process wastewater to > 99 % reduction before discharge into the environment.
Gopagoni, Sundeep. "Microstructure Evolution in Laser Deposited Nickel-Titanium-Carbon in situ Metal Matrix Composite." Thesis, University of North Texas, 2010. https://digital.library.unt.edu/ark:/67531/metadc33154/.
Full textConrad, Mason Christian. "An Experimental Investigation of Silicone-to-Metal Bond Strength in Composite Space Docking System Seals." Cleveland, Ohio : Case Western Reserve University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=case1244237964.
Full textTitle from PDF (viewed on 19 August 2009) Department of Mechanical & Aerospace Engineering Includes abstract Includes bibliographical references Available online via the OhioLINK ETD Center
Richard, Brandon Demar. "Thermal Infrared Reflective Metal Oxide Sol-Gel Coatings for Carbon Fiber Reinforced Composite Structures." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4569.
Full textBegg, Henry S. "Processing, structure and properties of Al-matrix composites." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:6b825394-f5a0-4087-a89a-1ec6ca091426.
Full textWatts, Michael Robert. "The analysis of diffraction measurements of internal strains in metal matrix composites." Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313918.
Full textPandolfo, Felipe Grazziotin. "Análise modal de materiais compósitos." reponame:Repositório Institucional da UCS, 2006. https://repositorio.ucs.br/handle/11338/201.
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A modal analysis procedure for composites is presented in this work. Procedures employed to aim this objective can be divided into three groups: mass-balance, image analysis and point-counting. The mass-balance methods are based on the determination of the chemical composition of the sample and on the prior knowledge of the composition of each phase, so to determine the phase concentration by solving a matrix of linear equations. Unfortunately, sometimes it is not possible, specially when two or more phases presentes similar compositions. Image analysis is done using different contrast settings to dicriminate phases and to estimate its volume fraction, based on the area filled by each one. The method may lead to wrong results due to overlapping grey levels. One may employ x-ray fluorescence maps to avoid such errors, although the technique is often very slow. The procedure proposed in this work uses the point-counting method with an automated phase identification, using x-ray spectral data, by means of a formerly trainned neural network. The phase quantities are estimated from the identification frequency of each phase in several points of the sample. The precision of the analysis can be controlled by the number of acquisition points. Almost all procedure has been automated. Data analysis is performed by a software ("Sherlock") developed for this purpose. To evaluate the proposed procedure, ceramic composite samples and a metal composite sample were analysed. These analyses supported the precision evaluation and some limitations of the technique, which may be compared to X-ray element mapping. Further, the proposed procedure can deal with other sources of phase data, making it easy to include organic phase identification into the modal analysis of composite material.
Hardian, Rifan. "Interplay between structure, texture, and reactivity in MOFs in the case of amorphous, defective, and composite materials." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0419/document.
Full textMetal-organic frameworks (MOFs) are a class of porous materials that constructed from metal clusters connected with organic linkers. The main objective of my PhD was to characterize the texture, structure, and reactivity of MOFs materials with a particular focus on defective, amorphous and composite materials. The first study is centered on the properties of the Fe-BTC family and this work was realized in collaboration with Utrecht University and the University of Oxford. A comparative study between crystalline MIL-100(Fe) and its commercial counterpart amorphous Basolite F300 (BASF) were studied by using methanol adsorption to predict the reactivity. Other characterization methods are introduced to investigate both materials which were further tested to be used as supports for metal-impregnation. In the next study, ball-milling was employed as a post-synthesis strategy for MOF modification. This ZIF-8 material was selected since it is commercially available (Basolite Z1200) and is becoming one of the reference materials in this area. Extensive studies including flexibility, textural, structural, as well as reactivity of different milling products is presented. Zirconium-based MOFs (UiO-66 and MOF-808) were also examined in this thesis. These studies were performed in collaboration with TU Munich. UiO-66 series containing engineered defects are first examined. We demonstrated that vapor adsorption measurement is a valuable tool to access the chemistry of the defects. The second studied system is MOF-808 series, where a comprehensive study is presented starting from synthesis strategies of defective and composite MOFs up to adsorption properties and reactivity
Breslin, Michael Craig. "Transformation Kinetics of Al2O3/Al Co-Continuous Ceramic/Metal Composite Materials (C4) Produced by a Displacement Reaction Between Liquid Al and Fused SiO2." The Ohio State University, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=osu1392902805.
Full textFan, Liangdong. "Development and characterization of functional composite materials for advanced energy conversion technologies." Doctoral thesis, KTH, Kraft- och värmeteknologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-134111.
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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 textCarvalho, Eduardo. "Estudo da variabilidade da tenacidade de concretos reforçados com fibras de aço por meio de ensaios à flexão em prismas moldados e extraídos." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/258577.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
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Resumo: O concreto reforçado com fibras de aço (CRFA) tem seu principal campo de aplicação nos pisos industriais e pavimentos. Em função das características de redistribuição de esforços que apresentam tais estruturas - placas apoiadas sobre uma base elástica - é possível a substituição total das armaduras convencionais pelas fibras de aço, acelerando o processo executivo e garantindo sua segurança e durabilidade. A introdução das fibras de aço nos concretos tem como principal função modificar o comportamento do compósito quando solicitado a esforços de flexão, transformando um material de natureza frágil em dúctil, ou seja, com capacidade de absorção de energia. A ductilidade desse compósito é usualmente quantificada pela medida de tenacidade do material em ensaios de tração na flexão, obtida com velocidade de deformação controlada, condição fundamental para avaliação do comportamento do compósito após sua fissuração. É importante salientar que a tenacidade do CRFA é fortemente influenciada pela distribuição das fibras na matriz de concreto, distribuição esta que é sensivelmente diferente em corpos de prova prismáticos moldados, utilizados para o controle de qualidade da obra, do que a encontrada nas estruturas dos pisos ou pavimentos. As propriedades do CRFA são expressas assumindo essa distribuição randomizada das fibras. Não obstante, em corpos de prova de tamanhos padronizados, ocorrem os efeitos de parede, também chamados de efeitos de borda. Esses efeitos consistem no alinhamento das fibras junto ao fundo e às laterais do corpo de prova, tornando o arranjo das fibras de aço nesses locais comprometido em virtude desses efeitos de parede. Com isto ocorre um aumento induzido no desempenho do compósito dado o alinhamento das fibras à direção principal de tensão durante a flexão. Buscando analisar a influência que a distribuição das fibras tem sobre a tenacidade do material, foram moldadas placas com dimensões que simulem os pisos e pavimentos (com três distintos teores de fibras: 20, 30 e 40 kg/m³), das quais foram extraídos prismas para determinação da suas tenacidades, que serão comparadas com as obtidas em prismas moldados. Os resultados foram cotejados estatisticamente, através da análise de variância, para estabelecimento das correlações existentes e suas influências sobre a tenacidade do compósito. Não há norma nacional para ensaios e utilização do CRFA que especifiquem e normatizem o seu uso. Dessa maneira, em virtude dos resultados dos valores de tenacidade terem sido com grande variabilidade, propusemos valores característicos para serem utilizados no controle executivo de obra
Abstract: The steel fiber reinforced concrete (SFRC) has in the industrial slabs-on-ground and the pavements its main field of application. Regarding the features of such structures and the redistribution of the resulting forces - slabs supported on elastic base - the complete substitution of the conventional armors for steel fibers has been possible saving time of the executive process, nevertheless security and durability also guaranteed. The introduction of steel fibers in the concrete has the mainly feature of modifying the behavior of the composite when requested the flexural efforts, transforming a material of fragile nature into ductile, which means; with capacity of energy absorption. The ductility of this composite usually is quantified by the measurement of the thoughness of the material in tensile stress in the flexural tests, obtained by controlled speed deformation, basic condition for evaluation of the behavior of the composite afterwards fissuration. It is important to point out that the toughness of the SFRC is mainly influenced by the distribution of fibers in the concrete matrix, distribution that is significantly different in prismatic specimen molded, used for the control of the quality of the construction, of what found in the structures of the slabs-on-ground and the pavements. The properties of the SFRC are express assuming this randomly distribution of the fibers. However, in specimen of standard sizes the wall effect occurs, also calls of edge effect. These effects consist in the alignment of the fibers next to botton and to the laterals of the specimen. This occurs with an induced increase in the performance of the composite given the alignment of fibers on the main direction of tension during flexion. In this way, an induced increase in the performance of the composite given the alignment of staple fibers to the main direction of tension occurs during the flexural test, becoming the arrangement of steel fibers in these places compromised due to these wall effects. Searching to analyze the influence that the distribution of staple fibers has on the toughness of the material, plates with dimensions were molded that simulate the slabs-onground and pavements (with three distinct staple fiber texts: 20, 30 and 40 kg/m³), of which prisms for determination of its toughness will be extracted, that will be compared with the gotten ones in molded specimen. The results will be statistically analyzed through the analysis of variance for establishment of the existing correlations and its influences on the toughness of the composite. There is no national standard for testing and use of the SFRC that specify and regulate their use. Thus, given the results of toughness values have been with great variability, we propose characteristic values for the application in executive control of building works
Mestrado
Arquitetura e Construção
Mestre em Engenharia Civil
Magill, Marvin D. "The influence of thermomechanical processing on the elevated temperature mechanical behavior of 6061 aluminum - alumina metal matrix composite materials." Thesis, Monterey, California: Naval Postgraduate School, 1990. http://hdl.handle.net/10945/27630.
Full textA cast, aluminum-based discontinuous metal matrix composite was thermomechanically processed. The material studied was 6061 aluminum containing 10 vol. pct. or 15 vol. pct. alumina (Al2O3) particles, fabricated by casting and subsequently extruded by Duralcan, Inc. of San Diego, CA. Processing included rolling the extruded bars to large strain values at 350 C and 500 C with controlled reheating between passes. Mechanical testing was conducted at temperatures and strain rates ranging from 200 C to 500 C and 6.7 x 10-5 s-1 to 3.3 x 10-1 s-1, respectively. This material displayed a tendency for increased elongation with an increase in the strain rate above 6.7 x 10-4 s-1. Elongation data for the 350 C rolled materials, containing both 10 vol. pct. and 15 vol. pct. alumina, displayed greater values at lower temperatures than the 500 C rolled materials. Values for strength agreed well with previous results.
Stjernstoft, Tero. "Machining of Some Difficult-to-Cut Materials with Rotary Cutting Tools." Doctoral thesis, KTH, Production Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3693.
Full textAutomobile and aero industries have an increasing interestin materials with improved mechanical properties. However, manyof these new materials are classified as difficult-to-cut withconventional tools. It is obvious that tools, cutting processesand cutting models has to be devel-oped parallel to materialsscience. In this thesis rotary cutting tools are tested as analternative toexpensive diamond or cubic bore nitridetools.
Metal matrix composites mostly consist of a light metalalloy (such as aluminium or titanium) reinforced with hard andabrasive ceramic parti-cles or fibres. On machining, thereinforcement results in a high rate of tool wear. This is themain problem for the machining of MMCs. Many factors affect thelife length of a tool, i.e. matrix alloy, type, size andfraction of the reinforcement, heat treatment, cuttingconditions and tool properties.
In tests, the Al-SiC MMC formed a deformation layer duringmilling, probably affected by lack of cooling. The dominatingfactor for tool life was the cutting speed. Water jet or CO2cooling of turning did not provide dramatic increase in toollife. With PCD, cutting speeds up to 2000 m/min were usedwithout machining problems and BUE formation. Tool flank wearwas abrasive and crater wear created an "orange-peel type" wearsurface. PCD inserts did not show the typical increase in flankwear rate at the end of its lifetime.
The use of self-propelled rotary tools seems to be apromising way to increase tool life. No BUE was formed on therotary tool at high cutting data. The measurements indicatethat the rotary tool creates twice as good surface as PCDtools. The longest tool life was gained with an inclinationangle of 10 degrees. Tool costs per component will beapproximately the same, but rotary cutting tool allows higherfeeds and therefore a higher production rate and thus a lowerproduction cost.
The rotary cutting operation might have a potential toincrease productiv-ity in bar peeling. The lack of BUE withrotary cutting gives hope on higher tool life. The test resultsshow that tool wear was 27% lower with rotary cutting tools.Increase of cutting speed from 22 to 44 m/min did not affectcutting forces. This indicates that the cutting speed canincrease without significant change in tool wear rate.
Issues related to rotary cutting like cutting models,cutting processes, standards, tools and models have beendiscussed. A tool wear model with kinetic energy has beendiscussed.
KEYWORDS:Difficult-to-Cut material, Metal MatrixComposite (MMC), Machining, Machinability, Rotary Cutting Tool,Acoustic Emission
Tkach, Suzanne G. "Experimental determination of heat transfer through metal foils and ceramic fiber mats during composite fabrication." Ohio : Ohio University, 1997. http://www.ohiolink.edu/etd/view.cgi?ohiou1184345240.
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