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Macrosegregation in steel ingotsPickering, Edward John January 2015 (has links)
No description available.
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Ingot homogenizationJennings, Theodore Lee 05 1900 (has links)
No description available.
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Investigation of panel crack formation in steel ingots using mathematical and physical modelsThomas, Brian Gordon January 1985 (has links)
An investigation of panel crack formation in steel ingots was undertaken
to improve understanding of the mechanisms by which they develop and to evaluate possible solutions to the problem. The investigation revealed that two distinct types of panel cracks, both of which are partly caused by intermediate-temperature embrittlement of steel involving aluminum nitride precipitation, operate under different mechanisms. Isothermal, physical modelling experiments were conducted to determine the flow patterns, velocity profiles and flame geometry in a bottom-fired soaking pit and the resultant effects on heat transfer. An investigation involving comparison with analytical solutions determined the optimum numerical method to employ for the mathematical modelling of complex, two-dimensional, transient, heat-conduction problems. This method was formulated to calculate the temperature distribution in a steel ingot during the various processing stages from initial casting up to rolling and was verified with industrial measurements. A transient, elasto-visco-plastic, thermal-stress model employing the finite-element method was formulated, developed and verified using analytical solutions. Based on the temperatures calculated by the finite-element, heat-transfer model as input data, the transient, internal stress state of the ingot was calculated, taking into account the effects of phase-transformation volume changes and kinetics, creep, and temperature-dependent mechanical property behavior. The simulated stress histories were found to be directly linked to the progress of the phase-transformation front and were used to clarify the role of stress generation in panel crack formation. Finally, the results of a metallurgical investigation of steel ingot samples containing off-corner panel cracks were synthesized with the results of the physical and mathematical models to determine mechanisms and to suggest solutions for the formation of both mid-face and off-corner panel cracks. Mid-face panel cracks are apparently formed during air cooling when the mid-face surface is between the Ar₁ and 500 °C. Off-corner panel cracks appear to initiate internally during the early stages of reheating, but do not propagate to the surface until air cooling after removal from the soaking pit. / Applied Science, Faculty of / Mining Engineering, Keevil Institute of / Graduate
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Computer simulation of macrosegregation in ESR ingotsFurlong, Robert Joseph. January 1977 (has links)
Thesis: M.S., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 1977 / Includes bibliographical references. / by Robert Joseph Furlong, Jr. / M.S. / M.S. Massachusetts Institute of Technology, Department of Materials Science and Engineering
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Oxhide ingots, copper production, and the mediterranean trade in copper and other metals in the bronze ageJones, Michael Rice 17 September 2007 (has links)
The production and trade in copper and bronze was one of the major features of the
complex societies in the Near East and Mediterranean during the third to first
millennia B.C. While finished metal objects are common finds from the period,
ancient metal ingots and hoards of scrap metal, as well as archaeological evidence of
metallurgical activities, are often more important sources of information for how
ancient technology and trade functioned. Shipwrecks, particularly those found off the
coast of Turkey at Uluburun and Cape Gelidonya, as well as mining and smelting sites
in the Mediterranean region, provide invaluable information on the production and
trade of copper and tin, the main ingredients of bronze. In this thesis, I examine the
evolution of the copper trade in the eastern and central Mediterranean, particularly
during the Late Bronze Age, when âÂÂoxhideâ ingots were widely exported. Finds of
oxhide ingots have increased dramatically in recent years, and no synthesis of all of
this newly available evidence is currently available. I attempt to analyze this new
evidence in relation to older finds and research, with a particular focus on the cargo of
the Uluburun shipwreck, the largest collection of Bronze Age metal ingots from a
single site in the Mediterranean. The history of oxhide ingot production is complex,
but by the Late Bronze Age Cyprus was supplying much of the copper used to
neighboring regions, with revolutionary effects on societies in Cyprus and elsewhere. The archaeological evidence shows that oxhide ingots are early examples of a
standardized industrial product made for export by emerging state-level societies
during the second millennium B.C. and fueled the development of international trade,
metallurgical technology, and complex social institutions in a variety of Mediterranean
societies from Egypt and the Levant, Greece, Cyprus, to Sardinia in the central
Mediterranean.
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Macrosegregation in electroslag remelted ingotsKou, Sindo January 1978 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1978. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Vita. / Includes bibliographical references. / by Sindo Kou. / Ph.D.
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Gold nanoparticles for biomedical applications synthesis, characterization, in vitro and in vivo /Kattumuri, Vijayalakshmi, January 2006 (has links)
Thesis (Ph.D.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on May 6, 2009) Vita. Includes bibliographical references.
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Modélisation mathématique simplifiée d'un four de métal chaud /Perron, Jean, January 1987 (has links)
Memoire (M.Sc.A.)--Universite du Quebec a Chicoutimi. 1987. / Bibliogr.: ff. 161-175. Document électronique également accessible en format PDF. CaQCU
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Modélisation tri-dimensionnelle et en régime transitoire des fours d'homogénéisation /Lavoie, Yvon, January 1993 (has links)
Mémoire (M.Eng.)-- Université du Québec à Chicoutimi, 1993. / Document électronique également accessible en format PDF. CaQCU
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Projeto e montagem de um sistema para lingotamento contínuo sob agitação eletromagnética para ligas de Al-Si / Design and assembly of a continuous casting system under a electromagnetic stirring to Al-Si alloysBeil, Wendel Leme, 1974- 27 August 2018 (has links)
Orientador: Eugênio José Zoqui / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-27T12:27:50Z (GMT). No. of bitstreams: 1
Beil_WendelLeme_M.pdf: 9441091 bytes, checksum: a79e3096e6d5e36f55c442eaac25c9ea (MD5)
Previous issue date: 2015 / Resumo: O presente trabalho visa desenvolver um projeto e executar a montagem e teste de um sistema de lingotamento contínuo, aprimorado com o uso da agitação eletromagnética, para a fabricação de lingotes de ligas de Al-Si com estrutura refinada de grãos. Durante seu desenvolvimento, o projeto almejou o estabelecimento de parâmetros construtivos do equipamento, bem como os parâmetros de processamento para obtenção dos lingotes. Os parâmetros estudados foram a altura de metal fundido na cavidade do molde, velocidade de lingotamento, temperatura de vazamento e rugosidade da cavidade do molde. Após serem determinados os parâmetros construtivos e de processamento, procedeu-se a obtenção dos lingotes propriamente ditos, em duas condições de refrigeração: refrigeração primária, somente no molde metálico, e refrigeração primária e secundária (com sistema de refrigeração na saída do lingote). Para cada uma dessas condições foram obtidos lingotes sem a aplicação do campo magnético e, sob a agitação eletromagnética a 1500 W com o campo magnético variando de 12 a 20 Gauss e 3000 W com o campo magnético variando de 22 a 38 Gauss. De posse dos lingotes seguiu-se a caracterização microestrutural por meio de análise metalográfica convencional e análise metalográfica por polarização de imagem, que buscou verificar a eficiência do sistema no refino de grãos. A condição de otimização alcançada sugere a fabricação de ligas de Al-Si nas seguintes condições: a temperatura de vazamento adotada foi de 800 ºC, rugosidade da cavidade do molde de Ra = 0,06 µm, velocidade de lingotamento 3 mm/s e altura de metal fundido na cavidade do molde de 15 a 20 mm, em que alcançou-se o tamanho de grãos com 178 µm e espaçamento interdendrítico de 125 µm, com uma potência de 1500 W e campo magnético de 12 a 20 Gauss / Abstract: This work aims to develop a project and implement the assembly and testing of a continuous casting system , enhanced with the use of electromagnetic stirring to manufacture ingots of Al-Si alloys with refined grain structure. During its development the project aspired to establishing constructive parameters of the equipment, as well as the establishment of the processing parameters for obtain ingots. The parameters studied were: the molten metal height in the mould cavity, the casting speed, the casting temperature, and the roughness of the mould cavity. After setting the construction and processing parameters were obtained obtain the ingots in two cooling conditions: primary cooling (considering only the metal mould), and primary and secondary cooling (with the ingot cooling system in the output). For each of these conditions were obtained ingots without applying the electromagnetic field and with electromagnetic stirring in 1500 W with a variation of electromagnetic field between 12 to 20 Gauss, and 3000 W with a variation eletrocmagnetic field between 22 to 38 Gauss. In possession of ingots followed the microstructural characterization by conventional metallographic analysis and metallographic analysis by polarization imaging, which aims to evaluate the efficiency of the grain refining system. The process optimized condition suggests the manufacturing Al-Si alloy in the following conditions: the pouring temperature was 800 °C, the mould cavity surface roughness Ra = 0.06 µm, casting speed is 3mm/s and molten metal height in the mould cavity of 15 to 20 mm where grain size up to 180 µm and interdendritic spacing of 125 µm, with a power of 1500 W and electromagnetic field of 12 to 20 Gauss / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica
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