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Submitted by admin tede (tede@pucgoias.edu.br) on 2017-02-23T14:37:32Z No. of bitstreams: 1 TÂNIA SOCORRO BORGES MOTA.pdf: 1972330 bytes, checksum: 2eb53c90ba517ec09d91e598864163c8 (MD5) / Made available in DSpace on 2017-02-23T14:37:32Z (GMT). No. of bitstreams: 1 TÂNIA SOCORRO BORGES MOTA.pdf: 1972330 bytes, checksum: 2eb53c90ba517ec09d91e598864163c8 (MD5) Previous issue date: 2016-11-29 / The research brings as object the PNE 2014-2024, Law n. 13.005/2014, and the PEEGO 2015-2025, sanctioned by the Goiás government through Law n. 18.969/2015. The overall objective is to analyze comparatively the PEE-GO - Instituted Plan - prepared with the participation of the educational community of Goiás in 40 public hearings, guaranteed as democratic spaces of manifestation of the stakeholders involved in them - and the Plan Instituinte - of the government of Goiás. Specific objectives propose the analysis of the plans, the goals and the strategies, establishing relations between the State Plan and democracy in the organization of the State System of Education in Goiás, observing historical questions and the existing tensions, as well as the recognition of differences and approximations established Between Institution and Institution plans. The problem is to recognize the convergences and divergences between the PNE and the PEE-GO. The qualitative approach with documentary analysis, combined with comparative studies as research methodology, allowed a greater apprehension of the differences and the approximations between the referred state plans. It is noted that education, as national and regional public social policy, is full of contradictions. The government's understanding remains that the development of education is geared to the interests of the market and capital. The study identifies the goals, noting also that the PEE-GO Instituinte was only partially successful, based on the state's public education policy, since it was not able to obtain its full approval. These plans serve as an analysis a critical approach to the history of educational policies, marked by debates in favor of education in Goiás, although the interests of the State have stood out from those of civil society. / A pesquisa traz como objeto o PNE 2014-2024, Lei n. 13.005/2014, e o PEE-GO 2015- 2025, sancionado pelo governo goiano, por meio da Lei n. 18.969/2015. O objetivo geral consiste em analisar comparativamente o PEE-GO - Plano Instituinte - elaborado com a participação da comunidade educacional goiana em 40 audiências públicas, garantidas como espaços democráticos de manifestação dos interessados nelas envolvidos - e o Plano Instituído - do governo de Goiás. Os objetivos específicos propõem a análise dos planejamentos, das metas e das estratégias, estabelecendo relações entre o Plano Estadual e a democracia na organização do Sistema Estadual de Educação em Goiás, observadas questões históricas e as tensões existentes, bem como o reconhecimento de diferenças e aproximações instauradas entre os planos Instituinte e Instituído. O problema aponta em reconhecer as convergências e as divergências existentes entre o PNE e o PEE-GO. A abordagem qualitativa com análise documental, combinada com estudos comparativos como metodologia de investigação possibilitaram uma maior apreensão das diferenças e das aproximações entre os planos estaduais referidos. Nota-se que a Educação, como política social pública nacional e regional, está repleta de contradições. Persiste o entendimento do governo de que o desenvolvimento da educação esteja voltado para os interesses do mercado e do capital. Resulta deste estudo a identificação das metas, observando, também, que o PEE-GO Instituinte logrou êxito apenas parcialmente, conforme a base na política pública de educação estadual, já que não conseguiu sua aprovação total. Esses planos servem de análise para uma abordagem crítica da história das políticas educacionais, marcadas por debates em prol da educação goiana, apesar de que os interesses do Estado terem sobressaído aos da sociedade civil.

Pour les structures aéronautiques, les zones sensibles à la corrosion sont principalement celles où le plan de protection de la structure peut être mis en défaut, comme à l’intérieur des joints de recouvrement (dénommé «lap joint» en anglais). Les assemblages de tôles métalliques réalisés par recouvrement en utilisant, par exemple le rivetage, peuvent présenter des défauts de contact et donc il peut exister un interstice entre les deux parties de l’assemblage. En général cet interstice est isolé de l’environnement extérieur par un mastic. Mais il y a un risque de piégeage d’humidité plus ou moins concentrée en ions agressifs qui peut provoquer des endommagements ou aggraver ceux initiés sur des défauts des revêtements. Le premier objectif de cette thèse est de développer une méthodologie permettant de reproduire, de manière contrôlée et de façon la plus représentative de cas réels, la corrosion d’un alliage d’aluminium 2024-T3 constituant un joint de recouvrement afin d’effectuer des observations complétées par des mesures chimiques et électrochimiques. Le deuxième objectif est de tester l’application de modèles de transport réactif (en milieu confiné) pour voir s’il est possible de simuler les réponses (chimiques ou électrochimiques) mesurées expérimentalement et donc de prédire sur le long terme l’évolution d’un assemblage. / For aircraft structures, corrosion sensitive areas are mainly those where the protection of the structure may suffer local breakdowns, as encountered inside lap joints. The assemblies of metal plates by overlapping (riveting) may present some defects in contact and consequently a gap can exist between the two parts of the assembly. Typically this gap is isolated from the outside environment by a sealant. But there is a risk of trapping of moisture more or less concentrated in aggressive ions which can induce corrosion or increase the damages initiated on coating defects. The first objective of this thesis is to develop a methodology to reproduce in a controlled manner and in the most representative way regarding actual cases, the corrosion of a lap joint made of aluminum alloy 2024- T3 plates, to perform not only observations but also chemical and electrochemical measurements. The second objective is to test the application of reactive transport models (in confined media) to check if it is possible to simulate the chemical or electrochemical changes recorded during experiments and thus to predict the long-term evolution of lap-joint in humid environment.

This thesis is focused on fatigue behaviour of aluminium alloy 2024-T351 in low cycle and extremely low cycle fatigue regime. Test specimens were firstly subjected to quasi-static tensile and compression tests to establish basic mechanical properties of the experimental material. Fatigue tests were conducted in strain-control mode, when cyclic plastic response and S-N curves were determined. All of the experiments were conducted at room temperature. Shapes of mechanical hysteresis loops are dependent on the strain amplitude and clearly exhibit cyclic plasticity of the alloy. Cyclic deformation curve was fitted by power regression function and subsequently compared with the tensile test. Experimental data of the S-N curves were fitted by Manson-Coffin and Wöhler-Basquin law. The discrepancy of the fatigue data was observed in the extremely low cycle fatigue regime. Based on this phenomenon, new regression function was used to overcome shortening of fatigue life in the extremely low cycle regime.

In recent times, application of aluminum alloys is favored in the transportation sectors such as the aerospace and automobile industries where reduced fuel consumption and greenhouse gas emission are major priorities. In these applications, these alloys can be exposed to dynamic shock loading conditions as in the case of car crash and birds’ collision during aircraft’s take-off or landing. This study therefore focused on the deformation and damage mechanisms in AA 2017, AA 2024 and AA 2624 aluminum alloys under both quasi-static and dynamic impact loading conditions. Cylindrical specimens of the selected aluminum alloys were investigated under both quasi-static loading at 3.2 x10-3 s-1 using an Instron R5500 mechanical testing machine and dynamic impact loading using the split Hopkinson pressure bar at strain rates ranging between 2000 and 8000 s-1. The effects of strain rate and temper condition on the microstructural evolution in the alloys during mechanical loading were studied. The electron backscatter diffraction (EBSD) technique was used to investigate the texture of the naturally-aged AA 2017 and AA 2624 alloys before and after dynamic shock loading. The contributions of the major alloying elements such as copper, magnesium and silicon to the microstructural evolution and deformation behavior of the alloys under the dynamic shock loading condition were also studied using the energy dispersive spectroscopy (EDS) technique. Results showed that the morphology and atomic distribution of particles in the investigated alloys are functions of the temper condition. The hardness of all the three alloys was higher in the age-hardened conditions than the annealed ones. Although deformation of the alloy under quasi-static compressive loading was dominated by strain hardening, flow softening leading to strain localization and formation of shear bands occurred once certain critical strain values were reached. Under both quasi-static and dynamic loading, the alloys with low Cu:Mg ratio (AA 2024 and AA 2624) showed higher mechanical strength in age-hardened condition than that with high Cu:Mg ratio (AA 2017). All the alloys in the annealed condition exhibited an enhanced plasticity and formability. Intense strain localization leading to formation of adiabatic shear bands (ASBs) was the principal contributor to failure in the alloys under dynamic impact loading. Both deformed and transformed bands were observed, with cracking occurring mainly along the transformed shear bands. The tendency for formation of adiabatic shear bands is observed to be a function of the alloy composition, temper condition, strain, strain rate and strain hardening rate. In the natural aging condition, AA 2024 showed the highest susceptibility to formation of ASBs followed by AA 2624 and AA 2017 in that order. On the other hand, AA 2024 has the least susceptibility in the artificially-aged condition. Occurrence of bifurcation of transformed bands in dynamic impacted specimens is dependent on temper condition, strain and strain rate. The mechanism of fracture of the precipitation hardened samples is typical of ductile fracture occurring sequentially by nucleation, growth, and coalescence of micro-voids processes within transformed band. Elongated grains were observed to arrest propagating shear band depending on the angle the band makes with elongated grains. The higher the angle of inclination of a shear band to the grain on its path, the higher the tendency of the grain to stop its propagation. Texture analysis of the impacted specimens of AA 2017-T451 and AA 2624-T351 shows that the former has a higher tendency for the evolution of ultra-fine DRX grains within the transformed shear band. High strain rate led to the development of CD//<111> orientations at the expense of CD//<110> orientations. Schmid factor calculations performed on few different orientations in the starting microstructure shows that CD//<110> is less susceptible to slip deformation and consequently underwent rotation to CD//<111>.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-02-01T21:46:56Z No. of bitstreams: 1 AnaMariaMoraisCosta_TESE.pdf: 3474957 bytes, checksum: b65f813d8586d9b93fe81fa787ad1b7a (MD5) / Approved for entry into archive by Elisangela Moura (lilaalves@gmail.com) on 2016-02-23T23:28:30Z (GMT) No. of bitstreams: 1 AnaMariaMoraisCosta_TESE.pdf: 3474957 bytes, checksum: b65f813d8586d9b93fe81fa787ad1b7a (MD5) / Made available in DSpace on 2016-02-23T23:28:30Z (GMT). No. of bitstreams: 1 AnaMariaMoraisCosta_TESE.pdf: 3474957 bytes, checksum: b65f813d8586d9b93fe81fa787ad1b7a (MD5) Previous issue date: 2014-10-30 / Esse trabalho analisou o protagonismo dos Movimentos Sociais no processo de constru??o e aprova??o do Plano Nacional de Educa??o (PNE 2014-2024) com ?nfase nas metas para a Educa??o Superior. Os questionamentos problematizadores da pesquisa s?o os seguintes: Em qual contexto hist?rico os Movimentos Sociais assumiram o acesso ? educa??o superior como direito social? Quais protagonistas se envolveram no debate em torno da pol?tica de educa??o superior no PNE (2014-2024)? Quais os confrontos e antagonismos est?o ali presentes? Qual o papel dos Movimentos Sociais na Confer?ncia Nacional de Educa??o (CONAE) e no F?rum Nacional de Educa??o (FNE)? Para respond?-los, articulou-se a pol?tica educacional proposta pelo PNE com as reivindica??es hist?ricas dos Movimentos Sociais pelo acesso ? educa??o como direito social, evidenciando o processo de constru??o das diretrizes, metas e estrat?gias nos contextos pol?ticos e sociais de articula??o, proposi??o e reivindica??o nos quais ocorreu a atua??o dos protagonistas para elabora??o e aprova??o desta pol?tica; assim como, os antagonismos identificados. Como aporte te?rico/metodol?gico adotou-se como empiria o estudo dos processos de constru??o e aprova??o do referido PNE inserido nos espa?os de participa??o coletiva, na constru??o de acordos e proposi??es como a Confer?ncia Nacional de Educa??o realizada em 2010, em Bras?lia/DF, as confer?ncias municipais, intermunicipais e estaduais, o F?rum Nacional de Educa??o (FNE) e a Comiss?o Especial da C?mara Federal que o precederam. Para an?lise dos documentos e depoimentos dos protagonistas dos Movimentos Sociais selecionados como sujeitos da pesquisa, os guias te?ricos e os fundamentos conceituais foram a sociologia das aus?ncias, sociologia das emerg?ncias e o procedimento de tradu??o propostos por Boaventura Santos (2005; 2006; 2007; 2010), em di?logo com outros guias te?ricos, como a teoria do reconhecimento social apresentada por Axel Honneth, Charles Taylor e Nancy Fraser (2001; 2003) e as no??es do confronto pol?tico e oportunidade pol?tica organizadas por Sidney Tarrow (2009). Partindo-se dessa base conceitual foi privilegiada a rela??o dos Movimentos Sociais com a pauta da educa??o brasileira quando direcionados para o PNE, analisada com base nas contribui??es de Germano (2013; 2011; 2008; 2007; 1982), Dourado (2011; 2010; 2006); Saviani (2014; 2010; 2009; 2007; 2004,), Gohn (2012; 2010; 1997; 1995), Dagnino (1994) e Scherer-Warren (1993), dentre outros autores que contribuem com o car?ter transdisciplinar desta pesquisa. As contribui??es desses autores propiciaram o entendimento da diversidade epistemol?gica encontrada nas experi?ncias desenvolvidas nos Movimentos Sociais - por meio de suas a??es em diversos espa?os sociais e institucionais, observando-se as conquistas obtidas na pol?tica educacional contida no PNE 2014-2024; bem como a compreens?o da luta pelo reconhecimento social e suas conex?es com os temas emergentes presentes no debate da educa??o nacional. Desse modo, o estudo apontou elementos que possibilitaram a confirma??o da tese de que a Pol?tica de Educa??o Superior aprovada no PNE 2014-2024 (Lei n? 13.005/2014) representa as resson?ncias das mobiliza??es e reivindica??es dos Movimentos Sociais pelo acesso ? educa??o como direito social inalien?vel. / Este trabajo analiz? el protagonismo de los Movimientos Sociales en el proceso de construcci?n y de aprobaci?n del Plan Nacional de Educaci?n (PNE 2014 - 2014) con ?nfasis en las metas para da Educaci?n Universitaria. Las cuestiones que problematizan la investigaci?n son: ?En qu? contexto hist?rico los Movimientos Sociales asumieron el acceso a la educaci?n universitaria com o un derecho social? ?Qu? protagonistas se involucraron en el debate sobre la pol?tica de educaci?n universitaria en el PNE (2014 - 2024)? ?Qu? confrontaciones y antagonismos est?n presentes all?? ?Cu?l es el papel de los Movimientos Sociales en la Conferenc ia Nacional de Educaci?n (CONAE) y en el Foro Nacional de Educaci?n (FNE)? Para contestarlas, articulamos la pol?tica educacional propuesta por el PNE con las reivindicaciones hist?ricas de los Movimientos Sociales por el acceso a la educaci?n como un dere cho social, evidenciando el proceso de construcci?n de las directrices, las metas y las estrategias en los contextos pol?ticos de articulaci?n, proposici?n y reivindicaci?n en los que se produjo la actuaci?n de los protagonistas para la elaboraci?n y la ap robaci?n de esta pol?tica, tanto cuanto los antagonismos identificados. Como aporte te?rico/metodol?gico adoptamos como objeto de estudio emp?rico los procesos de construcci?n y aprobaci?n del mencionado PNE dentro de los espacios de participaci?n colectiv a, en la construcci?n de acuerdos y proposiciones como la Conferencia Nacional de Educaci?n realizada en 2010 en Brasilia/DF, las conferencias municipales, intermunicipales y de los Estados, el Foro Nacional de Educaci?n (FNE) y la Comisi?n Especial de la C?mara Federal que lo antecedieron. Para el an?lisis de los documentos y de los testimonios de los protagonistas de los Movimientos Sociales seleccionados como sujetos de la investigaci?n, los gu?as te?ricos y los fundamentos conceptuales fueron la sociolo g?a de las ausencias, la sociolog?as de las emergencias y el procedimiento de traducci?n propuesto por Boaventura Santos ( 2005; 2006; 2007; 2010), en di?logo con otros gu?as te?ricos, como las nociones de confrontaci?n pol?tica y oportunidad pol?tica organ izadas por Sidney Tarrow (2009). Partiendo de esa base conceptual, privilegiamos la relaci?n de los Movimientos Sociales con la agenda de la educaci?n brasile?a cuando direccionados al PNE, analizada en base a las contribuciones de Germano (2013; 2011; 200 8; 2007; 1982), Dourado (2011; 2010; 2006); Saviani (2014; 2010; 2009; 2007; 2004,), Gohn (2012; 2010; 1997; 1995), Dagnino (1994) y Scherer - Warren (1993), entre los autores que contribuyen con el car?cter transdisciplinario de esta investigaci?n. Las cont ribuciones de estos autores propician el entendimiento de la diversidad epistemol?gica encontrada en las experiencias llevadas adelante en los Movimientos Sociales mediante sus actuaciones en los diversos espacios sociales e institucionales, observando las conquistas obtenidas en la pol?tica educacional contenida en el PNE 2014 - 2024, as? como la comprensi?n de la lucha por el reconocimiento social y sus conexiones con los temas emergentes presentes en el debate de la educaci?n nacional. De este modo, el est udio indica elementos que posibilitaron la confirmaci?n de la tesis de que la Pol?tica de Educaci?n Universitaria aprobada en el PNE 2014 - 2024 (Ley n? 13.005/2014) representa las resonancias de las movilizaciones y reivindicaciones de los Movimientos Socia les por el acceso a la educaci?n como un derecho social inalienable.

Manufacturing of aircraft parts is often complex and time-consuming, which has led to an increased interest in new manufacturing technologies in the Swedish industry such as additive manufacturing (AM). Additive manufacturing techniques could be a solution to meet the aircrafts’ demand since it contributes to an efficient manufacturing and allows a just-in-time production of complex metal parts in their final shape. However, the use of AM aluminum for aircraft applications is in a development phase and no surface treatment process exists. Thereby, it is of high interest to further investigate surface treatments for AM alloys. Currently at Saab AB, conventional aluminum alloys are generally anodized in tartaric sulphuric acid (TSA) to improve the corrosion resistance and adhesion properties of the metal. On the behalf of Saab AB, there is also an interest in establishing powder coating as a surface treatment. This master thesis’ purpose is to investigate the anodizing and adhesion properties for the two additive manufacturing alloys - AlSi10Mg and ScalmalloyⓇ, and compare it with the conventionally produced Al alloy 2024-T3. The anodization and the powder coating is examined by using following characterization techniques: profilometry, light microscopy, scanning electron microscopy and contact angle measurements. The results from the experimental part indicated successful anodizations for all the alloys and good adhesion properties for powder coating. This research is a first step in contributing to a better understanding of the anodic coating and adhesion properties for the AM samples ScalmalloyⓇ and AlSi10Mg

This thesis deals with relationship between tensile strength and hardness of aluminium alloys. The introduction provides an overview of aluminum aloys and their properties. In the following section there is an analysis of the processing of aluminum alloys. A large part is devoted to the course of precipitation hardening. The second part of the thesis contains a practical part, which describes the methodology of measuring hardness and tensile strength. The measurement process is described below. At the end, the measured data are processed into various graphs and their results are evaluated.

Slitiny hliníku řad 2XXX a 7XXX nejsou shledávány jako svařitelné s použitím tradičních metod svařování. Jsou však široce používány v leteckých a kosmických konstrukcích. Obvyklý způsob jejich spojování je pomocí nýtování. Nově vznikající technologie lineárního svařování třením rotujícím nástrojem (Friction Stir Welding - FSW) již ukázala slibné výsledky při svařování těchto slitin. V této práci jsme prozkoumali aplikace technologie FSW v leteckých konstrukcích zejména jako náhradu nýtování na panelech vyztužených stringery. Sestavili jsme výrobní postup pro daný panel a navrhli další kroky k jeho optimalizaci. Dále jsme sestavili znalostní bázi základních svařovacích parametrů a porovnali jsme nýtování a FSW na jednoduchém modelu využitím metody konečných prvků a s cílem identifikovat rozdíly v charakteru rozložení napětí v těchto vzorcích.

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