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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.
1

Factors influencing the Nucleation and Morphology of Crystallographic Type Etch Pits in Pure Iron.

Spink, Geoffrey 08 1900 (has links)
<p> Etch pits can be produced in iron whose shape reflects the crystallography of the crystal. It is shown that pit morphology can be adequately predicted from an orientation dependent dissolution theory. The influence of an air-formed surface oxide film on pit nucleation and morphology is demonstrated. </p> / Thesis / Master of Science (MSc)
2

Experimental Characterization of Influence of Gaseous Hydrogen on Fatigue Crack Propagation and Crack Tip Plasticity in Commercially Pure Iron / Caractérisation expérimentale de l'influence de l'hydrogène gazeux sur la propagation et la plasticité en pointe de fissure de fatigue dans le fer ARMCO

Shinko, Tomoki 26 March 2019 (has links)
L’objectif de cette étude est de caractériser expérimentalement la propagation de fissures de fatigue affectée par l’hydrogène (Hydrogen-Affected Fatigue Crack Growth, HAFCG) dans diverses conditions et de clarifier le mécanisme impliqué en se concentrant sur la plasticité en pointe de fissures. Pour cet objectif, dans une première étape, l’influence de l’hydrogène sur la déformation plastique a été étudiée à l’aide d’essais de traction effectués sur un fer commercialement pur, le fer Armco, sous hydrogène gazeux. Les résultats ont montré que l’effet de l’hydrogène sur la propagation des fissures après apparition de la striction est plus important que celui sur la déformation plastique uniforme. Le HAFCG a ensuite été étudié au moyen d’essais de fissuration pour diverses valeurs de l’amplitude de facteur d’intensité de contrainte ΔK, de pression d’hydrogène (PH2 = 3,5 et 35 MPa) et de fréquence de chargement (f = 0,02 - 20 Hz). Il a été révélé que les vitesses de propagation dans un régime à ΔK élevé étaient fortement augmentées par l'hydrogène, jusqu'à 50 fois plus élevé que celles dans l'air. Le mode de rupture est une rupture intergranulaire fragile dans un régime de propagation à faible ΔK, alors qu’on observe une rupture transgranulaire de type quasi-clivage dans un régime à ΔK élevé. La valeur de ΔKtr (valeur de ΔK déclenchant l'augmentation de la vitesse de fissuration) diminue en augmentant la pression PH2. En outre, la vitesse augmente en diminuant la fréquence f. Une fois que la fréquence devient inférieure à une valeur critique, la vitesse de fissuration diminue considérablement jusqu'au même niveau que celle sous azote. La plasticité en pointe de fissure a été analysée à plusieurs échelles par microscopie optique, par mesure de déplacement hors plan et par microscopie électronique à balayage par transmission de la structure de dislocation située immédiatement sous la surface de rupture (FIB/STEM). Aucune modification claire de la zone plastique monotone en pointe de fissure sous hydrogène n’a été observée, alors qu’une réduction drastique de la plasticité cyclique associée à l'augmentation de la vitesse a été identifiée. Sur la base des observations expérimentales, des modèles de mécanisme de fissuration intergranulaire induit par l'hydrogène impliquant la coalescence des micro-vides le long de joints de grain et de mécanisme de fissuration transgranulaire induit par l'hydrogène impliquant un clivage cyclique dû à la réduction de la plasticité en pointe de fissure ont été proposés. Trois critères caractéristiques de fissuration assistée par hydrogène (ΔKtr, gradient d'hydrogène (PH2 × f)1/2 et limite supérieure de vitesse de fissuration) ont été établis. Ces critères devraient être utiles pour améliorer la conception en fatigue et la fiabilité des équipements exposés à l'hydrogène gazeux. / The objective of this study is to experimentally characterize Hydrogen-Affected Fatigue Crack Growth (HAFCG) behavior under various conditions and clarify the mechanism by focusing on crack tip plasticity. For this objective, as a first step, the influence of hydrogen on plastic deformation has been investigated by means of tensile tests in a commercially pure iron, Armco iron, under gaseous hydrogen. The results of the tests pointed out that the hydrogen effect on crack propagation is more important than that on uniform plastic deformation. Then, the HAFCG was investigated by means of FCG tests under various conditions of crack tip stress intensity ΔK, hydrogen gas pressure (PH2 = 3.5 and 35 MPa) and loading frequency (f = 0.02 – 20 Hz). It has been revealed that the FCGRs in a high ΔK regime were highly enhanced by hydrogen up to 50 times higher than the one in air. The fracture mode was a brittle intergranular fracture in a low ΔK regime, while it is a brittle transgranular quasi-cleavage one in a high ΔK regime. The value of ΔKtr (value of ΔK triggering the FCGR enhancement) decreases by increasing the pressure PH2. Besides, the FCGR enhancement increases by decreasing the frequency f. Once f becomes lower than a critical value, the HAFCG rate significantly decreases down to the same level as in nitrogen., The crack tip plasticity was analyzed in a multiscale approach by means of optical microscopy, out-of-plane displacement measurement, and scanning transmission electron microscopy of dislocation structure immediately beneath the fracture surface (FIB/STEM). As a result, no clear modification of monotonic crack tip plasticity by hydrogen was observed, while a drastic reduction of cyclic crack tip plasticity associated with the FCGR enhancement was identified. Based on the experimental evidences, models of the hydrogen-induced intergranular FCG mechanism involving microvoid coalescence along grain boundary and the hydrogen-induced transgranular FCG mechanism involving cyclic cleavage due to crack tip plasticity reduction have been proposed. Three characteristic criteria of HAFCG (ΔKtr, hydrogen gradient (PH2 × f)1/2 and upper limit of FCGR) have been established. These criteria are expected to be useful for improving fatigue design and reliability of hydrogen-related equipment.
3

Avaliação da estabilidade microestrutural e sua influência nas propriedades magnéticas do ferro puro severamente deformado / Evaluation of thermal stability and its influence on the magnetic properties of severely deformed pure iron

Renzetti, Reny Angela 08 September 2008 (has links)
Atualmente existe um considerável interesse no processamento de materiais com estrutura ultrafina de grãos. Estes materiais podem ser obtidos por deformação plástica severa via extrusão por canal angular (ECAE). Durante ECAE, uma barra lubrificada é pressionada através de uma matriz rígida consistindo de dois canais de mesma seção transversal, os quais se interceptam a um ângulo ?. Cisalhamento simples é o mecanismo de deformação predominante e ocorre paralelamente ao plano de intersecção entre os dois canais. Este trabalho enfoca a estabilidade térmica e sua influência sobre as propriedades magnéticas de ferro puro severamente deformado por ECAE. Uma barra de ferro puro foi deformada em temperatura ambiente por múltiplos passes de ECAE (8 passes), usando uma matriz com ângulo de intersecção ??= 90º, resultando em uma deformação equivalente _N = 9,2. Esta barra foi girada de 90o depois de cada passe de extrusão. Amostras da barra deformada foram recozidas em várias temperaturas entre 100 e 800°C, variando-se o tempo de recozimento entre 1 e 120 min. Uma segunda barra de ferro puro foi deformada por um único passe de ECAE, com um ângulo ??= 120o, resultando em uma deformação equivalente _N = 0,67. Amostras retiradas desta barra foram recozidas em várias temperaturas entre 300 e 800°C por 15 min. Em uma condição correspondente à segunda barra, uma terceira foi deformada sendo o passe de ECAE interrompido. A caracterização microestrutural foi efetuada utilizando-se microscopias ótica e eletrônica de varredura, microdureza Vickers e textura via difração de raios X. Curvas de magnetização em função do campo magnético aplicado até cerca de 9 T foram obtidas para amostras representativas da barra deformada por múltiplos passes de ECAE. Foram determinados os intervalos de temperatura de recozimento em que ocorrem a recuperação e a recristalização para esta barra e para a barra deformada por um único passe de ECAE. Com relação à barra do ensaio interrompido, várias seções do plano normal à direção de extrusão da barra foram analisadas a fim de se investigar a evolução da textura durante extrusão em canal angular. Os resultados foram comparados com aqueles reportados para outros materiais deformados via ECAE com estrutura ccc e também com as texturas previstas pelo Modelo Visco-plástico Autoconsistente (do inglês VPSC model). / There is considerable current interest in fabricating ultrafine-grained materials. Such materials can be obtained by severe plastic deformation via equal-channel angular extrusion (ECAE). During ECAE, a lubricated billet is pressed through a rigid die consisting of two channels of the same cross section intersecting each other at an angle ?. Simple shear is the predominant deformation mechanism and occurs parallel to the intersecting plane of the channels. This work focuses on thermal stability and its influence on the magnetic properties of severely deformed pure iron via ECAE. A billet of pure iron was deformed at room temperature by multiple ECAE passes (8 passes), using a die angle ??= 90o, to a total equivalent strain of _N = 9.2. The billet was rotated by 90o after each extrusion pass. Samples of the deformed billet were annealed at several temperatures between 100 and 800oC, varying the annealing time from 1 to 120 min. A second billet of pure iron was deformed using 1-pass ECAE, with ??= 120o, with an equivalent strain of _N = 0.67. Samples of this billet were annealed at several temperatures between 300 and 800°C for 15 min. Corresponding to second condition, a third billet was deformed by interrupting the ECAE pass. Microstructural characterization was performed using optical and scanning electron microscopies, Vickers microhardness, and texture measurements via X-ray diffraction. Magnetization curves as a function of applied magnetic field up to 9 T were obtained for representative samples of the billet deformed by multiple ECAE passes. The annealing temperature ranges corresponding to recovery and recrystallization for this billet and 1-pass ECAE billet were determined. Regarding the interrupted 1-pass ECAE billet, several sections normal to the extrusion direction were analyzed in order to investigate the texture evolution during equal channel angular extrusion. The obtained results were compared to those ones found in other deformed bcc materials via ECAE and also by using the visco-plastic self-consistent (VPSC) model to predict the final texture.
4

Avaliação da estabilidade microestrutural e sua influência nas propriedades magnéticas do ferro puro severamente deformado / Evaluation of thermal stability and its influence on the magnetic properties of severely deformed pure iron

Reny Angela Renzetti 08 September 2008 (has links)
Atualmente existe um considerável interesse no processamento de materiais com estrutura ultrafina de grãos. Estes materiais podem ser obtidos por deformação plástica severa via extrusão por canal angular (ECAE). Durante ECAE, uma barra lubrificada é pressionada através de uma matriz rígida consistindo de dois canais de mesma seção transversal, os quais se interceptam a um ângulo ?. Cisalhamento simples é o mecanismo de deformação predominante e ocorre paralelamente ao plano de intersecção entre os dois canais. Este trabalho enfoca a estabilidade térmica e sua influência sobre as propriedades magnéticas de ferro puro severamente deformado por ECAE. Uma barra de ferro puro foi deformada em temperatura ambiente por múltiplos passes de ECAE (8 passes), usando uma matriz com ângulo de intersecção ??= 90º, resultando em uma deformação equivalente _N = 9,2. Esta barra foi girada de 90o depois de cada passe de extrusão. Amostras da barra deformada foram recozidas em várias temperaturas entre 100 e 800°C, variando-se o tempo de recozimento entre 1 e 120 min. Uma segunda barra de ferro puro foi deformada por um único passe de ECAE, com um ângulo ??= 120o, resultando em uma deformação equivalente _N = 0,67. Amostras retiradas desta barra foram recozidas em várias temperaturas entre 300 e 800°C por 15 min. Em uma condição correspondente à segunda barra, uma terceira foi deformada sendo o passe de ECAE interrompido. A caracterização microestrutural foi efetuada utilizando-se microscopias ótica e eletrônica de varredura, microdureza Vickers e textura via difração de raios X. Curvas de magnetização em função do campo magnético aplicado até cerca de 9 T foram obtidas para amostras representativas da barra deformada por múltiplos passes de ECAE. Foram determinados os intervalos de temperatura de recozimento em que ocorrem a recuperação e a recristalização para esta barra e para a barra deformada por um único passe de ECAE. Com relação à barra do ensaio interrompido, várias seções do plano normal à direção de extrusão da barra foram analisadas a fim de se investigar a evolução da textura durante extrusão em canal angular. Os resultados foram comparados com aqueles reportados para outros materiais deformados via ECAE com estrutura ccc e também com as texturas previstas pelo Modelo Visco-plástico Autoconsistente (do inglês VPSC model). / There is considerable current interest in fabricating ultrafine-grained materials. Such materials can be obtained by severe plastic deformation via equal-channel angular extrusion (ECAE). During ECAE, a lubricated billet is pressed through a rigid die consisting of two channels of the same cross section intersecting each other at an angle ?. Simple shear is the predominant deformation mechanism and occurs parallel to the intersecting plane of the channels. This work focuses on thermal stability and its influence on the magnetic properties of severely deformed pure iron via ECAE. A billet of pure iron was deformed at room temperature by multiple ECAE passes (8 passes), using a die angle ??= 90o, to a total equivalent strain of _N = 9.2. The billet was rotated by 90o after each extrusion pass. Samples of the deformed billet were annealed at several temperatures between 100 and 800oC, varying the annealing time from 1 to 120 min. A second billet of pure iron was deformed using 1-pass ECAE, with ??= 120o, with an equivalent strain of _N = 0.67. Samples of this billet were annealed at several temperatures between 300 and 800°C for 15 min. Corresponding to second condition, a third billet was deformed by interrupting the ECAE pass. Microstructural characterization was performed using optical and scanning electron microscopies, Vickers microhardness, and texture measurements via X-ray diffraction. Magnetization curves as a function of applied magnetic field up to 9 T were obtained for representative samples of the billet deformed by multiple ECAE passes. The annealing temperature ranges corresponding to recovery and recrystallization for this billet and 1-pass ECAE billet were determined. Regarding the interrupted 1-pass ECAE billet, several sections normal to the extrusion direction were analyzed in order to investigate the texture evolution during equal channel angular extrusion. The obtained results were compared to those ones found in other deformed bcc materials via ECAE and also by using the visco-plastic self-consistent (VPSC) model to predict the final texture.
5

Vývoj procesních parametrů technologie Selective laser melting pro výrobu tenkostěnných dílů z práškového železa / Development of process parameters of Selective laser melting technology for the production of thin-walled iron parts

Šreibr, Vít January 2018 (has links)
The thesis deals with the processing of pure iron by Selective laser melting technology as a material with good electromagnetic properties. The main area is the optimization of the production of thin-walled samples, which monitor the influence of process parameters on the thickness and quality of the wall surfaces. In addition to the perpendicular walls, walls built at an angle of 45° are also examined. Another phase of the thesis is the determination of process parameters for bulk bodies to achieve the lowest porosity and high surface quality. An important part of the research is the application of acquired knowledge in the production of samples designed to test magnetic properties as well as part for a specific application. These considerations concern not only the setting of the printing parameters, but also the heat treatment and its influence on the magnetic and mechanical properties of the material. Mechanical properties were determined by tensile tests and hardness tests. All samples were made on a SLM 280HL using a 400W ytterbium laser.
6

Crescimento de grão num fio de ferro comercialmente puro trefilado a frio / Grain growth in commercially-pure cold-drawn wires of iron

Almeida Junior, Davison Ramos de 29 April 2015 (has links)
Este trabalho tem como objetivo caracterizar as mudanças microestruturais durante o recozimento isotérmico de um fio de ferro trefilado a frio e de pureza comercial com ênfase no crescimento de grão. Os recozimentos foram realizados no intervalo de 823-1173 K por diversos tempos. As informações estatísticas do tamanho de grão foram obtidas por meio do método dos interceptos lineares. O mapeamento das orientações foi obtido por meio de difração de elétrons retroespalhados (EBSD). O material apresenta uma microestrutura ferrítica e totalmente recristalizada a partir de 873 K. Foram encontrados indícios de crescimento normal de grão a partir de 1023 K, porém este crescimento não evoluiu consideravelmente ao longo do tempo de tratamento. Os resultados obtidos a partir do método dos interceptos lineares demonstram que a distribuição de tamanho de grão segue uma curva próxima à log-normal. Nas amostras recozidas a partir de 1123 K, verificou-se a ocorrência de crescimento anormal de grão. O crescimento anormal de alguns grãos inicia-se na região central do fio, estendendo-se até uma região próxima à superfície do fio. Algumas modificações na dimensão da amostra e na atmosfera de recozimento foram realizadas a fim de se estudar a interação destas variáveis no desenvolvimento dos grãos anormais. Foram identificados indícios morfológicos de que o mecanismo para ocorrência de crescimento anormal foi o molhamento de contornos no estado sólido (solid-state wetting) que depois foram confirmados pelas análises de micro e mesotexturas. A análise de microtextura também revela que o material apresenta duas componentes preferenciais, as fibras || DT e || DT, onde DT é a direção axial de trefilação. A primeira orientação é a mais intensa, sendo que seu fortalecimento parece ser impulsionado pelo crescimento anormal de grão. A segunda é menos intensa e parece estar relacionada com as orientações dos grãos oriundos da recristalização primária. Aspectos teóricos e analíticos sobre o crescimento de grão são apresentados e associados aos resultados experimentais e à literatura. / This Dissertation aims follow the microstructural changes occurring during isothermal annealing of commercially-pure cold-drawn iron wire, with emphasys on grain growth phenomena. The grain size data were obtained by means of the linear intercept method. The orientations scanning were done by means of electron backscatter diffraction patterns (EBSD). Isothermal annealing was performed within the temperature range 823 - 1173 K for several times. The material displays full recrystallization at temperatures above 873 K. Normal grain growth was observed above 1023 K, although this growth did not evolve through longer annealing times. The results of the linear intercept method show the grain size distribution has a log-normal shape. For samples annealed above 1123 K, abnormal grain growth occurs. The first signs of secondary recrystallization appear close to the center of the wire, growing towards the surface. Changes in the wire diameter and annealing atmosphere were performed to assess the effect of these variables on abnormal grain growth. Results point out that abnormal grain growth is driven by solid-state wetting. These morphological observations were also confirmed by micro and mesotexture analyses. The microtexture also shows the presence of two major fiber texture components || WD and || WD, were WD is the axial wire-drawn direction. The first one is the most intense and its strengthening seems to be related with abnormal grain growth. The second one is weaker and it seems to be most related with small primary recrystallized grains. Theoretical and analytical features about grain growth are presented and discussed in light of literature and experimental results.
7

Evolution microstructurale du fer pur et d’un alliage Fe-Cr sous irradiation avec injection simultanée d’hélium : étude expérimentale et modélisation / Microstructural evolution of pure iron and a Fe-Cr alloy under irradiation with simultaneous injection of helium : experimental study and modeling

Brimbal, Daniel 02 December 2011 (has links)
Les aciers ferrito-martensitiques sont d’excellents candidats potentiels en tant que matériaux de structure dans les futurs réacteurs de fusion. A ce titre, ils devront résister à des flux intenses de neutrons de 14 MeV qui créeront des cascades de déplacements atomiques et des produits de transmutation tels que l’hélium. Afin de mieux comprendre le comportement de base de ces aciers sous irradiation en présence d’hélium, nous avons étudié les effets de l’hélium et ceux du chrome dans le cadre de ce travail de thèse. Du fer pur et un alliage modèle Fe-5,4%pds Cr ont ainsi été irradiés dans la plateforme JANNuS à 500°C en bi-faisceau avec des ions Fe+ et He+ et en mono-faisceau avec des ions Fe+. L’utilisation de cette plateforme a permis de suivre l’évolution du dommage jusqu’à des doses faibles (1 dpa) et de caractériser la microstructure après irradiation à forte dose (100 dpa). Elle a également permis l’observation in situ dans un MET couplé à deux accélérateurs des effets cinétiques d’implantation/irradiation. La nature et la répartition des défauts d’irradiation ont été déterminés : ce sont essentiellement des boucles de dislocations de vecteur de Burgers de type a<100> et des cavités/bulles. Nous avons montré que la co-implantation d’hélium et l’addition de chrome réduisent la mobilité des boucles. Par ailleurs, avec ou sans hélium, l’addition de chrome réduit le gonflement dans toutes les conditions étudiées. De plus, dans le fer pur irradié avec hélium, un phénomène original de germination hétérogène de cavités/bulles dans les plans des boucles a été mis en évidence. Enfin, nous avons également utilisé le code de dynamique d’amas CRESCENDO pour interpréter les résultats expérimentaux dans le fer pur irradié avec hélium. / Ferritic-martensitic steels are excellent potential candidates for a use as structural materials in future fusion reactors. For this application, they will have to withstand high fluxes of 14 MeV neutrons that will create atomic displacement cascades and transmutation reactions which will produce large quantities of helium. In order to understand the basic mechanisms under irradiation with helium, we have studied the effects of helium and those of chromium. Pure iron and a Fe-5.4 wt. % Cr model alloy were irradiated at the JANNuS platform in dual-beam mode with Fe+ and He+ ions and in single-beam mode with Fe+ ions at 500ºC. This platform enabled us to follow the evolution of damage up to low doses (1 dpa) and to characterize the microstructure at high doses (100 dpa). It also allowed us to observe in situ irradiation/implantation kinetic effects in a TEM coupled to two accelerators. The nature and distribution of irradiation defects was determined: they are essentially dislocation loops with a<100> Burgers vectors and cavities/bubbles. We have demonstrated that the co-implantation of helium and the addition of chromium both reduce the mobility of dislocation loops. The addition of chromium reduces swelling for all the irradiation conditions studied, with or without helium. In pure iron irradiated with helium, an original phenomenon was discovered for the first time: cavities/bubbles nucleate heterogeneously on the planes of the dislocation loops. We have also interpreted our experimental results in pure iron irradiated with helium using the cluster dynamics code CRESCENDO.
8

Crescimento de grão num fio de ferro comercialmente puro trefilado a frio / Grain growth in commercially-pure cold-drawn wires of iron

Davison Ramos de Almeida Junior 29 April 2015 (has links)
Este trabalho tem como objetivo caracterizar as mudanças microestruturais durante o recozimento isotérmico de um fio de ferro trefilado a frio e de pureza comercial com ênfase no crescimento de grão. Os recozimentos foram realizados no intervalo de 823-1173 K por diversos tempos. As informações estatísticas do tamanho de grão foram obtidas por meio do método dos interceptos lineares. O mapeamento das orientações foi obtido por meio de difração de elétrons retroespalhados (EBSD). O material apresenta uma microestrutura ferrítica e totalmente recristalizada a partir de 873 K. Foram encontrados indícios de crescimento normal de grão a partir de 1023 K, porém este crescimento não evoluiu consideravelmente ao longo do tempo de tratamento. Os resultados obtidos a partir do método dos interceptos lineares demonstram que a distribuição de tamanho de grão segue uma curva próxima à log-normal. Nas amostras recozidas a partir de 1123 K, verificou-se a ocorrência de crescimento anormal de grão. O crescimento anormal de alguns grãos inicia-se na região central do fio, estendendo-se até uma região próxima à superfície do fio. Algumas modificações na dimensão da amostra e na atmosfera de recozimento foram realizadas a fim de se estudar a interação destas variáveis no desenvolvimento dos grãos anormais. Foram identificados indícios morfológicos de que o mecanismo para ocorrência de crescimento anormal foi o molhamento de contornos no estado sólido (solid-state wetting) que depois foram confirmados pelas análises de micro e mesotexturas. A análise de microtextura também revela que o material apresenta duas componentes preferenciais, as fibras || DT e || DT, onde DT é a direção axial de trefilação. A primeira orientação é a mais intensa, sendo que seu fortalecimento parece ser impulsionado pelo crescimento anormal de grão. A segunda é menos intensa e parece estar relacionada com as orientações dos grãos oriundos da recristalização primária. Aspectos teóricos e analíticos sobre o crescimento de grão são apresentados e associados aos resultados experimentais e à literatura. / This Dissertation aims follow the microstructural changes occurring during isothermal annealing of commercially-pure cold-drawn iron wire, with emphasys on grain growth phenomena. The grain size data were obtained by means of the linear intercept method. The orientations scanning were done by means of electron backscatter diffraction patterns (EBSD). Isothermal annealing was performed within the temperature range 823 - 1173 K for several times. The material displays full recrystallization at temperatures above 873 K. Normal grain growth was observed above 1023 K, although this growth did not evolve through longer annealing times. The results of the linear intercept method show the grain size distribution has a log-normal shape. For samples annealed above 1123 K, abnormal grain growth occurs. The first signs of secondary recrystallization appear close to the center of the wire, growing towards the surface. Changes in the wire diameter and annealing atmosphere were performed to assess the effect of these variables on abnormal grain growth. Results point out that abnormal grain growth is driven by solid-state wetting. These morphological observations were also confirmed by micro and mesotexture analyses. The microtexture also shows the presence of two major fiber texture components || WD and || WD, were WD is the axial wire-drawn direction. The first one is the most intense and its strengthening seems to be related with abnormal grain growth. The second one is weaker and it seems to be most related with small primary recrystallized grains. Theoretical and analytical features about grain growth are presented and discussed in light of literature and experimental results.

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