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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Micro and nano composites composed of a polymer matrix and a metal disperse phase

Olea Mejía, Oscar Fernando. Brostow, Witold, January 2007 (has links)
Thesis (Ph. D.)--University of North Texas, Dec., 2007. / Title from title page display. Includes bibliographical references.
62

The effects of cooling on the flow strength of metal matrix composites /

Lulay, Kenneth Edward, January 1990 (has links)
Thesis (Ph. D.)--University of Washington, 1990. / Vita. Includes bibliographical references (leaves [146]-151).
63

Effect of chromium and manganese on corrosion behavior of Fe-TiC composites /

Reed, Izumi N., January 1998 (has links)
Thesis, (M.S.)--Oregon Graduate Institute of Science and Technology, 1998.
64

Processing and mechanical properties of metal-ceramic composites with controlled microstructure formed by reactive metal penetration /

Ellerby, Donald Thomas. January 1999 (has links)
Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 254-264).
65

Novel clay-based metal composites as applicable heterogeneous catalysts for the photo-assisted degradation of textile organic pollutants in water /

Yip, Chi Kin. January 2005 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references (leaves 95-101). Also available in electronic version.
66

Nanomechanical properties and nanotribology of ternary metal nitrides nanocomposite

Mihut, Dorina M. January 1900 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2006. / Title from title screen (site viewed May 23, 2007). PDF text: 205 p. : ill. ; 2.40Mb UMI publication number: AAT 3237051. Includes bibliographical references. Also available in microfilm and microfiche formats.
67

Feasibility of manufacturing ceramic based metal matrix composites (MMC) for multi-purpose industrial application

Madzivhandila, Takalani 02 November 2012 (has links)
M.Tech. / The mining industry exerts ever increasing demand for components with high wear resistance to the extent that plain ferrous alloys are falling short. Innovative metal-matrix composites nonferrous metals have been widely researched and used. Casting composites based on ferrous alloys pose monumental challenges in casting. Firstly, the density differential results in large resistant forces on the ceramic such that unless a rigid structure is configured, the less dense ceramic floats on the metal stream. Secondly, the poor wetting properties between metal and ceramic will result in inferior bonding of the matrix, hence separation of solids in service.This study presents the feasibility of manufacturing ceramic based metal matrix composites (MMC) for multi-purpose industrial application including wettability and the bonding between the matrix and the composite. The cold rods of alumina positioned in the mould prior to casting cracked as soon as they came in contact with hot metal. Because of the density difference between ceramic and liquid metal the alumina tended to float under the influence of Ferro static pressure. Infiltration of zirconia (ZrO2) and alumina (Al2O3) in ferrous matrix was investigated. Infiltration of liquid metal in ceramic filters increased with porosity of filters i.e. greater infiltration occurred in filters with larger pore volume fraction measured in terms of number of pores per linear inch (ppi). Thus, there was high infiltration in casting with 10ppi followed by 30ppi and there was poor infiltration in 50ppi ceramics. Infiltration increased with increasing temperature of the ceramics. A temperature of 1000oC was found to be superior to 800oC. The wetting behaviour of molten iron on the substrates of Al2O3 was investigated. Titanium in high chromium white cast iron was found to improve the wetting characteristics on alumina. The wetting angle decreased with increased titanium content. The wear properties of ferrous alloys used were not significantly improved by the ceramic used to make the composite. Filters are produced by a deposition process and hence are not densified for the purpose of manufacturing hard composites
68

Elastoplastic response of unidirectional graphite/aluminum under combined tension-compression cyclic loading

Lin, Mark Wen-Yih 17 November 2012 (has links)
A test fixture for combined tension-compression cyclic testing of unidirectional composites was designed and characterized using 606l-O aluminum specimens. The elastoplastic response of graphite/aluminum l5° off-axis and 90° specimens under tension-compression cyclic loading was subsequently investigated at three temperatures, -l50°F, room temperature and 250°F. The test results showed that the tensile response was predominantly elastoplastic, whereas the compressive response could not be characterized exclusively on the basis of the classical plasticity theory. Secondary dissipative mechanisms caused by inherent voids in the material's microstmcture had an apparent influence on the elastoplastic behavior in compression. At different test temperatures, the initial yield stress in tension and compression were translated in the tension direction with increasing temperature. This is believed to be caused by residual stresses induced in each phase of the composite. The micromechanics model proposed by Aboudi was subsequently employed to correlate the experimental and analytical results at room temperature. A semi-inverse methodology was incorporated to determine the in-situ properties of the constituents. Comparison between the analytical and experimental results showed good agreement for monotonic tensile response. For tension-compression cyclic loading, fairly good correlation was obtained for l5° specimens, but poor for 90° specimens. The major cause of the discrepancy is suggested to be caused by the secondary dissipative mechanisms. / Master of Science
69

Deformation processed IMC-reinforced metal matrix composites

Pete, Thobeka Portia 11 July 2009 (has links)
The feasibility of utilizing TiB₂-reinforced near-gamma TiAl intermetallic matrix composites (IMCs) as a reinforcing entity within a commercially pure Ti matrix was investigated. IMCs are "ceramic-like" at ambient to moderate temperatures, and “metallic-like" in their deformation behavior above their brittle-to-ductile transition temperature, thus IMCs create opportunities to create unique in-situ composite microstructures otherwise unattainable using conventional ceramic reinforcements. CP titanium composites reinforced with 20 vol% of near-gamma TiAl IMC were produced by powder blending and densifying via high temperature extrusion deformation processing. The microstructures of the in-situ processed composites were characterized in terms of size, aspect ratio and average spacing of the IMC reinforcement. The microstructural features were correlated to observed mechanical behavior of the composites relative to the unreinforced matrix. The results indicate that the strengthening is derived from microstructural changes within the matrix due to the presence of the IMC particles, and solid solution strengthening due to the diffusion of Al from the reinforcing IMC phase into the Ti matrix. The increase in flow strength due to the former contribution correlates with the inverse square root of the IMC interparticle spacing. / Master of Science
70

Investigation of the aging characteristics of lead-tin alloys high in lead content

Klawitter, William A., Gregg, Henry T. January 1950 (has links)
Master of Science

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