Dendritic Structures
Mostrando 1-12 de 64 artigos, teses e dissertações.
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1. An Experimental Study of the Solidification Thermal Parameters Influence upon Microstructure and Mechanical Properties of Al-Si-Cu Alloys
Metals solidification involves the transformation of the molten metal back into the solid state. Solidification structures impact heavily on the final product's characteristics. The microstructure effects on metallic alloys properties have been highlighted in various studies and particularly the dendrite arm spacing influence upon the mechanical properties s
Mat. Res.. Publicado em: 18/06/2018
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2. Predicting Secondary-Dendrite Arm Spacing of the Al-4.5wt%Cu Alloy During Unidirectional Solidification
Mechanical properties and performance of metallic materials depend on their microstructures. In order to develop engineering materials that match prescribed criteria and to enable design with multifunctional materials, it is essential to be able to predict their microstructural patterns, such as size, shape, and spacing of the dendritic structures observed i
Mat. Res.. Publicado em: 24/11/2016
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3. Estudio de estructuras de cis- y trans-estilbeno mediante microscopiade fuerza atómica
ABSTRACTNanotechnology is a multidisciplinary field that emerged in recent years due to the development of tools to "see", study and manipulate matter at atomic and molecular levels. Stilbene and some of its derivatives are organic molecules found in nature, which have chemical structures of interest in nano-fabrication of molecular machine building blocks (
Matéria (Rio J.). Publicado em: 2015-09
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4. Avaliação da expressão de receptores e ligantes Notch nas populações de linfócitos T em desenvolvimento, linfócitos T reguladores naturais e células dendríticas no timo humano / Evaluation of the expression of Notch receptors and ligands in developing lymphocytes, natural regulatory T cells and dendritic cells in human thymus
The thymus is a primary lymphoid organ responsible of maturing T lymphocytes, where specialized structures and cells are observed. The intrathymic signaling during lymphocytes maturation is unclear. Among them, Notch signaling pathway, which comprises in receptors (Notch1-4) and ligands (DLL1, 2 and 3, Jaaged1 and 2), may regulate this process. In this work
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 10/09/2012
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5. AVALIAÃÃO DO REVESTIMENTO A BASE DE LIGA DE NÃQUEL EM AÃO ESTRUTURAL, EMPREGANDO O METAL DE ADIÃÃO ERNiCrMo-3 ATRAVÃS DA SOLDAGEM MIG/MAG / EVALUATE OF NICKEL WELD OVERLAY IN STRUCTURAL STEEL, WITH EMPLOYMENT OF GMAW ERNiCrMo-3 ELECTRODE.
The use of nickel alloy cladding components could be more frequently in petroleum industry. The crescent naphthenic corrosion and high molecular weight of national petroleum contribute for needs of materials with more resistance to corrosion, to temperature and to pressure. At this way, how part of systematic study, this work pretends to define operational r
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 04/04/2008
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6. Microestrutura de solidificação e propriedades mecanicas de ligas Sn-Zn para soldagem e recobrimento de superficies / Solidification microstructure and mechanical properties of Sn-Zn alloys for welding and deposition
Sabe-se que existem tendências de leis e diretrizes que restringem o uso e aplicação de certas substâncias perigosas utilizadas em processos de fabricação de componentes em geral. Como exemplo, podem-se citar produtos contendo cádmio, mercúrio, cromo hexavalente, bifenilos polibromatos, éteres difenil-polibromato e chumbo. Devido a essas restriçõe
Publicado em: 2008
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7. Cellular structures, cellular/dendritic transition and dendritic structures during transient unidirectional solidification / Estruturas celulares, transição celular/dendritica e estruturas dendriticas na solidificação unidirecional transitoria
As morfologias das estruturas de solidificação, caracterizadas principalmente por arranjos celulares e dendríticos, e suas grandezas representadas por espaçamentos celulares e dendríticos primários, secundários e terciários, controlam os perfis de segregação e a formação de segundas fases dentro das regiões intercelulares ou interdendríticas, q
Publicado em: 2007
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8. The influence of the initial microestructure and die material de thixoforming of A356 alloy / Influencia da microestrutura inicial e material de molde na tixoconformação da liga A356
This research aims the influence of initial microstructure and die material on thixofonning of A356 alloy. Obtained slurries are produced and tested in thixoforging operation by three distinct processes: controlled partial melting of coarse dendritic structures, controlled partial melting of ultra-refined structures and obtained slurries by liquid mechanical
Publicado em: 2007
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9. The influence of melt convection on dendritic spacing of downward unsteady-state directionally solidified Sn-Pb alloys
Microstructures are the strategic link between materials processing and materials behavior. A dendritic structure is the most frequently observed pattern of solidified alloys. The microstructural scales of dendrites, such as primary and secondary arm spacings, control the segregation profiles and the formation of secondary phases within interdendritic region
Materials Research. Publicado em: 2006-03
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10. Macroscopic modeling of columnar dendritic solidification
This paper deals with the derivation of a macroscopic model for columnar dendritic solidification of binary mixtures using the volume averaging method with closure. The main originalities of the model are first related to the explicit description of evolving heterogeneities of the dendritic structures and their consequences on the derivation of averaged cons
Computational & Applied Mathematics. Publicado em: 2004-12
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11. Caracterização da microestrutura dendritica na solidificação vertical descendente de ligas AL-CU / Characterization of dendritic array during downward transient directionally solidified AL-CU alloys
The dendritic spacings are important microstructural parameters, involved in solidification processes. They can affect not only microsegregation profiles but also the formation of secondary phases within interdendritic regions, which influences mechanical properties of cast structures. A small number of studies have been carried out in order to analyze the e
Publicado em: 2004
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12. Production of rheocast slurries by partial melting through alternative thermomechanical treatments
The production of alloys with rheocast structure, where the primary phase consists of globularized particles, by partial melting, involves grain recrystallization and secondary phases melting. In the process known as SIMA (Strain Induced Melt Activation), the raw material is cold deformed by a two-step rolling, making it little efficient. This work investiga
Journal of the Brazilian Society of Mechanical Sciences and Engineering. Publicado em: 2003-04