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Wang, Yun. "Solidification microstructure selection and coupled eutectic growth in Al-Fe and Al-Fe-Mn alloys". Thesis, University of Sheffield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324449.
Pełny tekst źródłaConrod, Kevin. "The hot working characteristics of Al-0.65% Fe, and Al-0.5% Fe-0.5% Co conductor alloys". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0021/MQ54324.pdf.
Pełny tekst źródłaУстинова, Е. В., i Е. В. Суховая. "Структурообразование квазикристаллических сплавов Al–Ni–Fe". Thesis, Сумский государственный университет, 2015. http://essuir.sumdu.edu.ua/handle/123456789/40674.
Pełny tekst źródłaPayne, Matthew A. "High-throughput Screening of Alloy Oxidation Across Al-Fe-Ni and Al-Fe-Ni-Cr Composition Space". Research Showcase @ CMU, 2016. http://repository.cmu.edu/dissertations/863.
Pełny tekst źródłaЛуценко, Евгений Валентинович, i Анатолий Иванович Зубков. "Прочность и электропроводность вакуумных конденсатов Al-Fe". Thesis, Институт физики металлов им. М. Н. Михеева Уральского отделения Российской академии наук, 2013. http://repository.kpi.kharkov.ua/handle/KhPI-Press/14471.
Pełny tekst źródłaTathgar, Harsharn S. "Solubility of Nickel in Mg-Al, Mg-Al-Fe, and Mg-Al-Mn Systems". Doctoral thesis, Norwegian University of Science and Technology, Department of Materials Technology, 2001. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-2019.
Pełny tekst źródłaThe corrosion properties of magnesium alloys strongly depend on the alloy composition and impurities. Heavy elements like nickel, and iron have low solubility in solid magnesium. The dissolved elements in molten magnesium precipitate out on solidification and form intermetallic particles that are the cause of corrosion. Iron content should be kept below the standards specified by ASTM B94/94 using aluminium and manganese. Manganese forms intermetallic particles with iron and aluminium thereby lowering the solubility of iron, and these particles are cathodic compared to magnesium matrix. No method for the removal of nickel has been known previously. Dissolution was the only method to lower the nickel content. Published solubility data for nickel in pure magnesium is inconsistent and not available for magnesium alloys. Therefore various systems are studied to determine the behaviour of nickel in Mg-Al alloys. Methods for removal of nickel from Mg-Al alloys are also discussed.
Machado, Vagner de Oliveira. "Estudo das propriedades magnetostrictivas da liga (Fe0,80Al0,20)97B3 obtida por solidificação direcional". Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/97/97134/tde-14092016-174334/.
Pełny tekst źródłaIn this work, bars of the alloy (Fe0,80Al0,20)97B3 were obtained by directional solidification (DS) in diameters of 3 and 4 mm, with the goal of improving the magnetostriction of the material through the introduction of texture. Production steps of the bars involved the manufacture of the alloy ingots, L1, L2, L6, by arc melting, then machining (M) or hot swaging (F). The greatest length that was achieved in a bar was 50 mm. The presence of boron in the samples was identified by scanning electron microscopy and energy dispersive spectroscopy, due to the presence of an eutectic microstructure that has dendrites and a microconstituent formed of phases ? and Fe2B. Results obtained by X-ray diffraction indicates that the bar L1 at the diameter of 4 mm showed preferential orientation in the directions , which caused a significant decrease of the magnetostriction compared to the same sample of the bar of diameter 3 mm. Magnetization measurements as a function of applied magnetic field (Ha) reveal that the saturation magnetization of the samples having boron is in average 181 Am2/kg, suggesting that the samples have ~ 2% of boron. The bars obtained by DS, thermally treated (CTT ) at 1100 ° C for 6 h, achieved higher magnetostrictions (? = ?l/l) compared to the samples without heat treatment.The highest value was 73 ? 10-6 was obtained in the longitudinal direction of the bar L1F in the diameter of 3 mm (L1F3-CTT). The maximum sensitivity factor d?/dH found as a function of the bars lengths was d?/dH = 0.9 x 10-9 m/A for an aspect ratio of ? = 12. Values of anisotropic constant K1, calculated using experimental results suggest that in some samples occur partial ordering of the cubic phase matrix , so there is the coexistence of phases Fe3Al ( D03 ) and ?.
Feitosa, Francisco Riccelly P. "Obtenção e evolução da fase icosaedral quasicristalina em ligas Al-Cu-Fe e Al-Cu-Fe-B por Melt-Spinnin". Universidade Federal da Paraíba, 2009. http://tede.biblioteca.ufpb.br:8080/handle/tede/5349.
Pełny tekst źródłaCoordenação de Aperfeiçoamento de Pessoal de Nível Superior
Melt spinnng processing is one of the most common processes to obtaining quasicrystaline structures. This is because of the fast cooling rate it imposes on the system, favoring such type of structure. This work deals with the production of quasycristaline phases (Al60Cu27,5Fe12,5 e Al57Cu27,5Fe12,5B3) via melt-spinning. The alloys were initially cast via induction melting under atmospheric air, with the designed chemical composition of the quasicrystals. Hence, the ribbons were produce by melt-spinning were characterized by means of x-ray diffraction and scanning electron microscopy. The results indicate that the icosahedral ψ - Al65Cu20Fe15 phase formed in both types of starting compositions. It seams that the boron contributes to stabilize the icosahedral phase.
O processo melt-spinning por imprimir altas taxas de resfriamento, é um dos principais meios para a obtenção de ligas com estrutura quasicristalinas, sendo o primeiro método utilizado para produzir materiais quasicristalinos. Neste trabalho utilizou-se este processo para a elaboração das ligas quasicristalinas Al(60-x)Cu25Fe15Bx, Al(60-x)Cu27,5Fe12,5Bx e Al(65-x)Cu20Fe15Bx (x=0 e x=3%at de boro). As ligas foram previamente fabricadas, por fusão, em atmosfera de argônio, em forno à indução, para em seguida serem submetidas ao processo melt-spinning , onde se obteve o material na forma de fita. As amostras foram caracterizadas por difração de raios-x e microscopia eletrônica de varredura. Os resultados indicaram a formação da fase icosaedral ψ - Al65Cu20Fe15 nas composições estudadas e uma provável contribuição do boro na produção dessa fase icosaedral
Beauchesne, Jean-Tristan. "Structures atomiques des phases icosaédriques de type F et dislocations". Phd thesis, Université Paris Sud - Paris XI, 2008. http://tel.archives-ouvertes.fr/tel-00274636.
Pełny tekst źródłaDans cette étude nous avons d'abord construit une structure générique permettant de traiter dans un seul schéma les phases icosaédriques de type F connues. Afin de valider ce modèle nous avons synthétisé quelques compositions suggérées par ce dernier. Ces synthèses ont permis entre autres de découvrir deux nouvelles phases quasipériodiques à la stoechiométrie Al66,08Cu21,35Mn8,29Fe4,28 , l'une icosaédrique (métastable) de type F et l'autre décagonale (stable). Elles ont montré, à une composition au-delà de celles déjà étudiées dans le système (Al,Pd,Fe), l'existence d'une phase F-IQC.
Globalement, ces résultats expérimentaux d'études de nouvelles phases icosaédriques ont permis de montrer la fiabilité du modèle : sur les trois essais de nouvelles compositions, deux ont montré l'existence de phases icosaédriques de type F et la troisième a mis en évidence une phase décagonale en relation d'épitaxie canonique avec la phase icosaédrique brut métastable (axe 10 confondu avec un axe 5).
Possédant un modèle fiable nous avons donc pu y introduire des dislocations. Nous avons ainsi précisé la géométrie des dislocations à l'échelle atomique, hors de la zone de cœur, dans les phases F-IQC. Dans cette structure nous avons aussi identifié les mouvements des phasons et tenté d'apporter des éléments de réponse aux mouvements de ces dislocations.
Delamare, José. "Etude microstructurale d'alliages Nd-Fe et Nd-Fe-Al : corrélation aux phases secondaires des aimants Nd-Fe-B". Rouen, 1992. http://www.theses.fr/1992ROUES058.
Pełny tekst źródłaNoetzel, Joachim. "Nanostruktur ionenbestrahlter Fe/Al- und Co/Cu-Grenzschichten". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2000. http://nbn-resolving.de/urn:nbn:de:swb:14-994414088062-09838.
Pełny tekst źródłaTemizel, Guvenc. "Intermetallic Phase Formation At Fe-al Film Interefaces". Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607589/index.pdf.
Pełny tekst źródłaЛуценко, Евгений Валентинович, В. В. Белозеров i Анатолий Иванович Зубков. "Структура нано и микрокристаллических вакуумных конденсатов Al-Fe". Thesis, Институт физики металлов им. М. Н. Михеева Уральского отделения Российской академии наук, 2014. http://repository.kpi.kharkov.ua/handle/KhPI-Press/14394.
Pełny tekst źródłaDong, Chuang. "Structure et formation des quasicristaux et des phases cristallines approximantes dans les alliages Ti-Fe, Al-Cu-Fe(-Cr), Al-Cu-Co(-Si) et Al-Pd-Mn". Vandoeuvre-les-Nancy, INPL, 1991. http://docnum.univ-lorraine.fr/public/INPL_T_1991_DONG_C.pdf.
Pełny tekst źródłaRanganathan, Sathees. "Rapid solidification behaviour of Fe and Al based alloys". Doctoral thesis, KTH, Materialvetenskap, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11325.
Pełny tekst źródłaQC 20100805
Bazzi, Gessica Dias. "Estudo de revestimentos a base de ligas Fe-AL". reponame:Repositório Institucional da UFPR, 2012. http://hdl.handle.net/1884/26967.
Pełny tekst źródłaStephen, Gail. "Al-Fe-Si intermetallics in 1000 series aluminum alloys". Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=26424.
Pełny tekst źródłaIn the first part of this study, the conditions at which the intermetallics form, along with the ability of strontium to modify them were investigated. The second part consisted of determining how the morphology of the Al-Fe-Si phases affects the mechanical properties of the worked product. It was found that the formation of the Chinese Script morphology is promoted with increasing cooling rates, Fe/Si ratios and additions of strontium. However, the relative amount of Chinese Script was found to decrease with increasing (Fe+Si) levels. Tensile testing and formability testing (Erichsen ball punch deformation test) revealed that the presence of a Chinese Script morphology of Al-Fe-Si intermetallics (as opposed to the plate-like morphology) imparts no significant beneficial effect on the formability of the final rolled sheet.
Луценко, Евгений Валентинович, В. В. Белозеров, Анатолий Иванович Зубков, Галина Ивановна Зеленская i А. А. Журбий. "Структура и физико-механические свойства вакуумных конденсатов Al-Fe". Thesis, Национальный научный центр "Харьковский физико-технический институт", 2014. http://repository.kpi.kharkov.ua/handle/KhPI-Press/14393.
Pełny tekst źródłaMadel, Caroline. "Elektronische Transporteigenschaften von amorphem und quasikristallinem Al-Cu-Fe". [S.l. : s.n.], 2000. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB9494963.
Pełny tekst źródłaMaggs, Steven James. "Intermetallic phase selection in dilute Al-Fe-Si alloys". Thesis, University of Leeds, 1996. http://etheses.whiterose.ac.uk/4711/.
Pełny tekst źródłaWilhelmi, James. "Giant Non-Joulian Magnetostriction in Fe-Al Single Crystals". Master's thesis, Temple University Libraries, 2019. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/566535.
Pełny tekst źródłaM.S.M.E.
A series of measurements aimed at comparing the magneto-elastic response and non-Joulian properties (magneto-volume) of single crystals of the iron-aluminum alloys Fe_81.8 Al_18.2 with different thermal treatments were per formed; the results of which confirmed net volume expansion in all field orientations. The magnitude of this expansion varied largely across various magnetic field alignments, with a greater than four times larger expansion for fields parallel to the [010] crystal axis than the [100] axis. The magnitude and direction of the change in volumetric expansion from quenched crystals to slow cooled crystals also depended heavily on the orientation of the magnetic field, with reduced magneto-volume responses ranging from ~2.4 to 0.5 times smaller for fields parallel to the [100] and [110] crystal axes respectively. These results present evidence of the non-Joulian effect and places crystals of the iron aluminum alloy Fe_81.8 Al_18.2 within the realm of functional non-Joulian magnets.
Temple University--Theses
Freitas, Augusto dos Santos. "Aplicação de campo efetivo e da técnica de Monte Carlo ao estudo de ligas Fe-Al". Universidade Federal de Sergipe, 2012. https://ri.ufs.br/handle/riufs/5352.
Pełny tekst źródłaIn the present work, we study the magnetic properties in the site diluted two-state Ising model on a body-centered cubic lattice. As an application of this study, we has been obtained the phase diagram for Fe-Al alloys and comparisons between theoretical model and experimental data are made by using the exchange interaction between Fe atoms in the alloy up to the third power dependence on concentration q of Al atoms. We have used the differential operator technique to expand the analytical expressions that arise from the diluted Ising model and describe such behavior by means of magnetic clusters with one and two spins. A good agreement between the theoretical model and experimental data is also obtained for both the magnetization and to the lattice parameter, r as a function of q. In this approach, it is shown as a good alternative to other analytical and computational techniques used for the study of diluted magnetic systems. The analytical results obtained for bcc lattice were compared with the Monte Carlo technique to determine the degree of applicability of the model and confirm the validity of the results obtained analytically.
Neste trabalho, aplicamos o modelo de Ising com diluição por sítios ao estudo das propriedades magnéticas de uma rede cúbica de corpo centrado (do inglês, body centered cubic, bcc), cujos sítios podem ser ocupados por spins. Como aplicação desse estudo, traçamos alguns diagramas de fase da liga Fe-Al, com comparações entre o modelo teórico utilizado e dados experimentais e propomos uma interação de troca entre os atomos de Fe, na liga, com dependência at´e terceira potência da concentração (q) de atomos de Al, possibilitando um melhor ajuste entre teoria e experimento para o diagrama T-q desta liga. Tomamos como base a t´ecnica do operador diferencial para expandir as express oes anal´ıticas que surgem do modelo de Ising dilu´ıdo e descrevemos tal comportamento magn´etico por meio de aglomerados com 1 e 2 spins. Um bom acordo entre o modelo te´orico proposto e dados experimentais tamb´em ´e obtido tanto para a magnetização como função de q quanto para o par ametro de rede, r, como função de q, sendo que esta abordagem mostra-se como uma boa alternativa a outras t´ecnicas anal´ıticas e computacionais utilizadas para o estudo de sistemas magn´eticos dilu´ıdos. Os resultados anal´ıticos obtidos para a rede bcc foram comparados com a t´ecnica de Monte Carlo para verificar o grau de aplicabilidade do modelo bem como confirmar a validade dos resultados encontrados analiticamente.
Kangouei, Navid. "Study of Equilibrium State in Fe-Mn-Al-C Alloys". Thesis, KTH, Termodynamisk modellering, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-148223.
Pełny tekst źródłaPrecHiMn (RFSR-CT-2010-00018)
Li, Xiaolin [Verfasser], Gerhard [Gutachter] Dehm i Easo P. [Gutachter] George. "Al-rich Fe-Al based alloys / Xiaolin Li ; Gutachter: Gerhard Dehm, Easo P. George". Bochum : Ruhr-Universität Bochum, 2017. http://d-nb.info/1129452034/34.
Pełny tekst źródłaLens, Arnaud. "Mobilité des joints de grains dans les alliages Al-Mn et Al-Fe-Si". Saint-Etienne, EMSE, 2004. http://www.theses.fr/2004EMSE0004.
Pełny tekst źródłaExperimental grain boundary mobilities were studied with an in-situ SEM/EBSD technique in order to understand the recrystallization and grain growth processes in relevant, close to industrial Al-Mn alloys. Therefore, an in-situ technique was developed for annealing between 200°C to 450°C. Theoretical velocities estimated from the approaches of the solute drag theories of Cahn, Lucke and Stuwe were compared to the experimental results. Several Al-Fe-Si alloys were studied in order to validate some ideas of Doherty concerning abnormal grain growth in the presence of low angle grain boundaries and precipitates. Moreover, mobilities were measured during normal and abnormal grain growth at 600°C
Aviziotis, Ioannis. "Chemical vapor deposition of Al, Fe and of the Al13Fe4 approximant intermetallic phase : experiments and multiscale simulations". Thesis, Toulouse, INPT, 2016. http://www.theses.fr/2016INPT0100/document.
Pełny tekst źródłaFilms containing intermetallic compounds exhibit properties and combination of properties which are only partially explored. They carry potential solutions to confer multifunctionality to advanced materials required by industrial sectors and to become a source of breakthrough and innovation.Metalorganic chemical vapor deposition (MOCVD) potentially allows conformal deposition on, and functionalization of complex surfaces, with high throughput and moderate cost. For this reason, it is necessary to control the complex chemical reactions and the transport mechanisms involved in a MOCVD process. In this perspective, computational modeling of the process, fed with experimental information from targeted deposition experiments, provides an integrated tool for the investigation and the understanding of the phenomena occurring at different length scales, from the macro- to the nanoscale. The MOCVD of Al-Fe intermetallic compounds is investigated in the present thesis as a paradigm of implementation of such a combined, experimental and theoretical approach. Processing of the approximant phase Al13Fe4 is particularly targeted, due to its potential interest as low-cost and environmentally benign alternative to noble metal catalysts in the chemical industry. The attainment of the targeted Al13Fe4 intermetallic phase passes through the investigation of the MOCVD of unary Al and Fe films. The MOCVD of Al from dimethylethylamine alane (DMEAA) in the range 139oC-241oC results in pure films. Increase of the deposition temperature yields higher film density and decreased roughness. The Aldeposition rate increases to a maximum of 15.5 nm/min at 185oC and then decreases. Macroscopic simulations of the process predictdeposition rates in sufficient agreement with experimental measurements, especially in the range 139oC-227oC. At higher temperatures, competitive gas phase and surface phenomena cannot be captured by the applied model. Multiscale modeling of the process predicts the RMS roughness of the films accurately, thus allowing the control of properties such as electrical resistivity which depend on the microstructure. The MOCVD of Fe from iron pentacarbonyl, Fe(CO)5, is investigated in the range 130oC-250oC for the possibility toobtain fairly pure Fe films with low Oand C contamination. The surface morphology depends strongly on the temperature and changes are observed above 200oC. The Fe deposition rate increases up to 200oC, to a maximum of 60 nm/min, and then decreases. Moreover, the deposition rate decreases sharply with increasing pressure. Computational predictions capture accurately the experimental behavior and they reveal that the decrease athigher temperatures and pressures is attributed to the high gas phase decomposition rate of the precursor and to inhibition of the surface fromCO. The multiscale model calculates RMS roughness in good agreement with experimental data, especially at higher temperatures. Upon investigation of the two processes, aseries of Al-Fe co-depositions performed at 200oC results in Al-rich films with a loose microstructure. They contain no intermetallic phases and they are O-contaminated due to the reaction of the Al with the carbonyl ligands. Sequential deposition of Al and Fe followed by in situ annealing at 575oC for 1 h is applied to bypass the Ocontamination. The process conditions of Fe are modified to 140oC, 40 Torr and 10 min resulting in O-free films with Al:Fe atomic ratio close to the targeted 13:4 one. Characterization techniques including X-ray diffraction, TEM and
Kumar, Golden. "Structural and magnetic characterization of Nd-based Nd-Fe and Nd-Fe-Co-Al metastable alloys". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2005. http://nbn-resolving.de/urn:nbn:de:swb:14-1118153436094-69139.
Pełny tekst źródłaFerguson, David Bruce. "Characterization of high damping Fe-Cr-Mo and Fe-Cr-Al alloys for naval ships application". Thesis, Monterey, California. Naval Postgraduate School, 1988. http://hdl.handle.net/10945/22942.
Pełny tekst źródłaKumar, Golden. "Structural and magnetic characterization of Nd-based Nd-Fe and Nd-Fe-Co-Al metastable alloys". Doctoral thesis, Technische Universität Dresden, 2004. https://tud.qucosa.de/id/qucosa%3A24505.
Pełny tekst źródłaDucher, Roland. "Contribution à l'étude du diagramme de phase ternaire Fe-Ti-Al et des équilibres Fe-TiAl". Toulouse, INPT, 2003. http://www.theses.fr/2003INPT005G.
Pełny tekst źródłaTaravel, Condat Carol. "Influence des conditions d'élaboration sur la microstructure de solidification lors de la trempe sur roue d'alliages Fe₇₅Al₂₅ et Fe₍₇₅-ₓ₎Al₂₅Bₓ₍₀, ₀₅₋₁₎ (pds%)". Grenoble INPG, 1991. http://www.theses.fr/1991INPG0106.
Pełny tekst źródłaBauer, Birgitta. "Einkristallzüchtung und Charakterisierung Al-reicher komplexer metallischer Phasen in Al-Cr-Fe und benachbarten Systemen". Diss., lmu, 2010. http://nbn-resolving.de/urn:nbn:de:bvb:19-120188.
Pełny tekst źródłaEl, Kabir Tarik. "Etude de matériaux composites à matrice base Al renforcés par des particules Al-Cu-Fe". Poitiers, 2007. http://www.theses.fr/2007POIT2342.
Pełny tekst źródłaQuasicrystalline (QC) materials exhibit remarkable mechanical properties at low and intermediate temperatures, such as high hardness together with high elastic modulus. One of the potential applications of QC materials is to use them as the reinforcement phase of composite materials. This study reports about processing, microstructures and mechanical properties of Al-based metal matrix composites (MMC) reinforced by QC particles. Five Al-based MMC were produced using the gas pressure infiltration technique. Al3Mg2, Al, Al-Cu-Mg and Al-Mg-Si matrices were used. They were reinforced by 50 % vol. Fraction of Al-Cu-Fe QC particles. The as-produced composites are rather complex and various phases are formed during the production process. These phases were identified to result from diffusion of both the aluminium and the copper. These composites are characterised by high flow stresses, that are unfortunately accompanied by numerous cracks whatever the temperature deformation. Two composites with an Al matrix initially reinforced by QC particles were prepared by hot isostatic pressing (HIP). With this technique two-phase composites are obtained, but depending on the processing temperature, the reinforcement particles are either of i-phase or !-phase. It is observed that ! particles contribute more positively to the improvement of the mechanical properties than the QC particles. The temperature dependences of "0. 2% suggest that the plastic deformation of the composite Al/!-Al-Cu-Fe is controlled by thermally activated mechanisms. In the composite Al/i-Al-Cu-Fe, in addition to thermally activated mechanism, the contribution of the internal stresses to the hardening of the composite must be taken into account
Krawczyk, Jacek. "Otrzymywanie oraz charakterystyka kompozytów typu kryształ - kwazikryształ stopów Al-Cu-Fe i Al-Cu-Co". Doctoral thesis, Katowice : Uniwersytet Śląski, 2011. http://hdl.handle.net/20.500.12128/5298.
Pełny tekst źródłaKANDEL, LAURENT. "Etude des proprietes magnetiques et electroniques des phases quasicristallines al-mn et al-cu-fe". Paris 11, 1992. http://www.theses.fr/1992PA112281.
Pełny tekst źródłaLaplanche, Guillaume. "Synthèse et caractérisation de la phase ω-Al7Cu2Fe et de composites Al/Al-Cu-Fe". Poitiers, 2011. http://nuxeo.edel.univ-poitiers.fr/nuxeo/site/esupversions/f121f0d6-5db1-44cc-9ee3-bbc6f5c3ff59.
Pełny tekst źródłaIn the general context of study of Al/Al-Cu-Fe composites, ω-Al7Cu2Fe phase and related Al/ω composites have been synthesised and their mechanical properties and microstructure investigated. Dense monolithic ω-Al7Cu2Fe phase synthesis was achieved for the first time using hot isostatic pressing and spark plasma sintering allowing for mechanical and microstructural investigations. Microindentation, compression and transient tests as well as mechanical spectroscopy have been performed in large temperature ranges. A brittle-to-ductile transition between 650 K and 820 K is evidenced. The stress-strain curves exhibit an upper yield stress followed by a softening or steady state stage only. The upper yield stress shows strong temperature dependence suggesting that deformation mechanisms are highly thermally activated. The evolution of activation volumes with the applied stress exhibits two deformation mechanisms with a transition temperature of 900 K. Transmission electron microscopy observations of deformed material reveal inhomogeneous dislocation distribution. The original results on the crystalline ω-Al7Cu2Fe phase exhibit a strong similarity with the well-known properties of the related icosahedral Al-Cu-Fe phase and shed a new light on the understanding of plasticity in these complex materials. Two Al/ω composites have been fabricated from powder metallurgy, one at 673 K from initial ω particles, the second at 823 K from initial icosahedral Al-Cu-Fe particles. Transmission electron microscopy observations reveal a complex matrix microstucture with different particles distribution according to the processing temperature. From compression and transient tests performed at various temperatures and in-situ compression test under neutron beam, the reinforcement of Al matrix is attributed to both load transfer and hardening of the matrix resulting from different microstructure
Ozyurda, Akin Halit. "Spray Rolling Of Rapidly Solidified Al-fe-v-si Alloy". Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607312/index.pdf.
Pełny tekst źródłaStrahl, Alexander. "Anelastische Relaxationen durch Punktdefekte und Versetzungen in Fe-Al-Legierungen". Berlin dissertation.de, 2006. http://www.digibib.tu-bs.de/?docid=00017200.
Pełny tekst źródłaHumphreys, Elen Siobhain. "Production and characterisation of rapidly solidified Al-V-Fe alloys". Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302070.
Pełny tekst źródłaPark, Woonsup. "Migration kinetics of antiphase boundaries in Fe-Al ordered alloys". Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/54326.
Pełny tekst źródłaMartinez, Celis Mayerling. "Transformation de phases et comportement à l'oxydation d'alliages Fe-Al". Toulouse, INPT, 2007. http://ethesis.inp-toulouse.fr/archive/00000504/.
Pełny tekst źródłaThe numerous good properties of alloys based on Fe-Al compounds still make them good candidates for industrial applications (good strength, good oxidation resistance, low production cost). This thesis word focuses on two characteristics of such alloys: i) microstructural defects, with emphasis on defects linked to ordering and ii) high temperature oxidation. We have studied four different alloys : a binary Fe-40Al, two alloys with additional elements (Fe-40Al- 0. 01B and Fe-40Al-2. 7Ni-0. 02B) and a semi-industrial alloy (grade 3 including alloying elements – Ni, Mn, Cr, Mo, B – and Y2O3 particles). Diffusion couples were also elaborated between these alloys and iron, which allowed to study diffusion and produce specimens with a varying aluminium content. The microstructural characterisation helped us to determine the precise nature of the complex planar faults observed in boron containing alloys. The study of diffusion couples was performed by chemical analysis and by characterising by transmission electron microscopy the antiphase domains due to the ordering that occurred during thermal treatments. These results reveal the incidence of alloy composition on diffusion and transformation temperatures. We showed that nickel addition slows down diffusion kinetics and seems to expand the stability domain of B2 phase. Oxidation kinetics study has been achieved by thermo gravimetric analysis performed at 800 and 1000°C on the different Fe- l alloys and on specimens extracted from the diffusion couples. Mass gain results complemented by X ray diffraction and SEM observations allow determine the oxides formed depending on the specimen composition. We could show thus determine the minimum aluminium content needed to impede iron oxidation (19 at. %) and we highlighted the effect of nickel on oxidation kinetics
Устинова, Е. В., i Е. В. Суховая. "Структурообразование квазикристаллических сплавов Al-Cu-Fe, легированных Si и B". Thesis, Сумский государственный университет, 2014. http://essuir.sumdu.edu.ua/handle/123456789/39445.
Pełny tekst źródłaZuazo, Rodriguez Ian Alberto. "Evolution microstructurale dans les alliages légers Fe-Al-Mn-C". Grenoble INPG, 2009. http://www.theses.fr/2009INPG0054.
Pełny tekst źródłaIn this work emphasis is put on the clarification of the complex microstructural evolution in multiphase lightweight steels. In the first part of this investigation detailed sequences of phase transformations are proposed and the domains where austenite is stable are given. Then isothermal growth kinetics of austenite was measured. Kinetics was modeled with known binary and ternary models. The DICTRA software provided only a qualitative description due to the shortcomings of the thermodynamic database. A deep-etching procedure together with the EBSD technique provided a correlation between morphology of the K-phase and orientation relationships with ferrite. Isothermal growth kinetics was measured in two morphologies of the K-phase. Modeling of the K-phase required a better knowledge of phase equilibria to yield proper results
Martinez, Celis Mayerling Viguier Bernard. "Transformation de phases et comportement à l'oxydation d'alliages Fe-Al". Toulouse : INP Toulouse, 2008. http://ethesis.inp-toulouse.fr/archive/00000504.
Pełny tekst źródłaQuehen, Hélène. "Étude métallurgique d'alliages intermétalliques Fe₃Al-Cu élaborés par fonderie". Electronic Thesis or Diss., Université de Lorraine, 2023. https://docnum.univ-lorraine.fr/ulprive/DDOC_T_2023_0359_QUEHEN.pdf.
Pełny tekst źródłaThe development of complex metallic alloys, of which HEAs are a paragon, requires at least the knowledge of the nature of the phases on the whole multicomponent phase diagrams, at least beyond the proximity of the binary systems on which they are based. The Fe-Al-Cu system is one of the most important ternary systems, even if its study has mainly focused on the Al rich corner because of its propensity to form quasi-crystalline phases. In this context, and in order to complete the knowledge in the intermediate regions between Fe₃Al and Cu₃Al, which are less explored, we have carried out a characterization study of a series of alloys elaborated by casting and subjected to heat treatments generally used to optimize the properties of Fe₃Al intermetallics. In a first step, we completed the ternary sections at 600°C and 700°C and highlighted the quantitative differences with the literature diagrams on the boundaries of the FeAl/Cu₃Al/Cu₉Al₄ three-phase domain. In a second step, we focused on alloys distributed along the Fe-28Al-XCu (X = 15, 20 and 25 at.%) and Fe-XAl-15Cu (X = 20 and 30 at.%) axes. We have characterized the microstructures in the as-solidified state and after different thermal treatments by electron microscopy (scanning and transmission) and X-ray diffraction (laboratory and high energy). We have highlighted the quasi-systematic presence of two intermetallic phases: Fe₃Al and Cu₃Al 18R, resulting from the martensitic transformation of Cu-rich regions. Their proportion is reversed according to the position in the microstructure generated by the solidification step: while Cu₃Al populates cuboidal domains distributed in the dendritic core composed mainly of Fe₃Al, one observes in the copper-rich interdendritic zones Fe₃Al platelets dispersed in a Cu₃Al matrix. It appears that the heat treatments usually applied to Fe₃Al alloys do not fundamentally alter this microstructure, except that they tend to globularize the different Cu-rich domains
Bekker, Viacheslav. "Entwicklung neuartiger thermisch stabiler weichmagnetischer Fe-Co-Al-N- und Fe-Co-Ta-N-Dünnschichtmaterialien für Hochfrequenzanwendungen". Karlsruhe : FZKA, 2005. http://bibliothek.fzk.de/zb/berichte/FZKA7169.pdf.
Pełny tekst źródłaSantos, Claudio Teodoro dos. "Efeito das adições de boro na magnetostricção de ligas policristalinas dos sistemas Fe-Al e Fe-Ga". Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/97/97135/tde-08102013-083643/.
Pełny tekst źródłaMagnetostrictive materials exhibit elastic deformation when subjected to a magnetic field or changing in magnetic properties when subjected to mechanical stress, so they are of great interest for applications in actuators, sensors and energy harvesters. However, the best available magnetostrictive materials are expensive and fragile. In the last years has been discovered a new class of magnetostrictive material which overcome this problem, the class of the Fe-Ga and Fe-Al alloys, which have the unusual combination of moderate magnetostriction, good mechanical properties and low associated cost. Currently, research has searched ways to improve the magnetostriction of these alloys, both for ternary additions of other atoms or by using different methods of preparation, heat treatment or mechanical processing. In the present study, we evaluated the effect of B additions and rapid solidification process on the microstructure and magnetostriction of Fe- Al and Fe-Ga alloys. For this purpose, polycrystalline alloys of nominal composition (Fe80Al20)1-0.01yBy, (Fe80Ga20)1-0.01yBy and (Fe72Ga28)1-0.01yBy, with y = 0, 0.5, 1, 1.5 e 2 at.% were produced by arc melting and splat cooling rapid solidification technique. Microstructural characterization of the samples was performed by SEM/EDS and XRD. The magnetostriction was measured under magnetic field of 0 to ±2 T, at 4.2, 77 and 300 K, by capacitance dilatometry. The B additions caused precipitation of Fe2B at the grain boundaries of A2 and/or D03 phase of Fe-Al and Fe-Ga alloys, resulting in a reduction of the grain size and formation of dendritic crystals. The Fe80Al20 alloys showed a maximum magnetostriction of 74 ppm with the addition of 2 at.% B. And, the Fe80Ga20 and Fe72Ga28 alloys showed a peak with the addition of 1 at.% B, of 81 ppm and 143 ppm, respectively. We concluded that these B additions had a beneficial effect on the magnetostriction of Fe- Al and Fe-Ga as-cast alloys, since they caused an increase up to 100% of this property in relation to the alloy without B. On the other hand, the rapid solidification had no the same effect on the magnetostriction of Fe-Al-B alloys.
Silva, Antonio Augusto Araújo Pinto da. "Thermodynamic modeling and critical experiments on the Al-Fe-Nb system". Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0148.
Pełny tekst źródłaThe equilibrium diagrams are the starting point and the guideline to predict and control the microstructure that will form during processing materials. Despite experiments being necessary in binaries and ternaries systems, it is difficult to experimentally determine phase diagrams of higher orders systems over wide ranges of compositions and temperature. The CALPHAD (CALculation of PHAse Diagrams) method was developed in order to solve this problem. The essence is to optimize the parameters of thermodynamic models that describe the Gibbs free energies of each phase aiming to reproduce the experimental and estimated (ab-initio) data. The compound energy formalism (CEF) is widely used in order to describe phases which present several sublattices. It allows the modeling of a large variety of phases and numerous methods have been developed to treat different situations. The activities in this work developed a new approach of the CEF (NACEF) based on a mathematic analysis of the parameters which leads to a new formulation of the Gibbs free energy function evolving new independent parameters in which new independent parameters are obtained to express the Gibbs free energy. This approach was used in this work to describe the intermetallic phases with two-sublattice in which the only defect type is anti-sites (A,B)a(A,B)b. The Al-Fe-Nb system was chosen due to its importance for the manufacturing process of several families of alloys currently used, e.g. steels, light alloys, and also for the development of new materials for high temperatures application. The binaries Al-Nb and Fe-Nb were reassessed and the Al-Fe-Nb system was assessed for the first time using literature information and new experimental data
Os diagramas de equilíbrio são o ponto de partida e a diretriz para prever e controlar a microestrutura ao final do processamento de um material. Apesar de experimentos serem necessários em sistemas binários e ternários, é muito difícil determinar experimentalmente diagramas de fase de sistemas de ordens superiores numa vasta amplitude de composições e temperatura. A fim de solucionar este problema, o método CALPHAD (CALculation of PHAse Diagrams) foi desenvolvido. A essência consiste em aperfeiçoar os parâmetros de modelos termodinâmicos que descrevem as energias livres de Gibbs de cada fase de modo a reproduzir as informações experimentais ou estimadas (ab-initio). O compound energy formalism (CEF) é amplamente utilizado para descrever fases que apresentam várias sub-redes. Ele permite a modelagem de uma grande variedade de fases e vários métodos têm sido desenvolvidos para o tratamento de diferentes situações. As atividades deste trabalho ajudaram a desenvolver uma nova abordagem para o CEF (NACEF) com base em um estudo matemático dos seus parâmetros termodinâmicos que levou a uma nova formulação para função da energia livre de Gibbs envolvendo novos parâmetros independentes. Esta nova abordagem tem sido utilizado como parte do presente trabalho para modelar fases intermetálicas binárias constituídas de sub-redes cujo único defeito é do tipo anti-sítio (A,B)a(A,B)b. O sistema Al-Fe-Nb foi escolhido devido a sua importância para o processo de fabricação de diversas famílias de ligas usadas atualmente, e.g. aços, ligas leves e, além disto, é um sistema importante para o desenvolvimento de materiais para aplicações em altas temperaturas. Neste trabalho os binários Al-Nb e Fe-Nb foram reavaliados e o sistema Al-Fe-Nb foi modelado pela primeira vez utilizando as informações da literatura e novos dados experimentais
Zienert, Tilo [Verfasser], Andreas [Akademischer Betreuer] Leineweber, Andreas [Gutachter] Leineweber, Hans [Gutachter] Flandorfer i Olga [Gutachter] Fabrichnaya. "Predicting heat capacity and experimental investigations in the Al-Fe and Al-Fe-Si systems as part of the CALPHAD-type assessment of the Al-Fe-Mg-Si system / Tilo Zienert ; Gutachter: Andreas Leineweber, Hans Flandorfer, Olga Fabrichnaya ; Betreuer: Andreas Leineweber". Freiberg : Technische Universität Bergakademie Freiberg, 2018. http://d-nb.info/1221070843/34.
Pełny tekst źródłaZapico, Alvarez David. "Mechanisms and kinetics of the galvannealing reactions on Ti IF steels". Thesis, Châtenay-Malabry, Ecole centrale de Paris, 2014. http://www.theses.fr/2014ECAP0019.
Pełny tekst źródłaHot-Dip GalvAnnealed (HDGA) coatings are produced by the immersion of the steel strip into an iron-saturated liquid zinc bath at around 460 °C containing small amounts of aluminium (from 0.1 to 0.135 wt.%, normally) and its subsequent heating (up to temperatures around 500-530 °C for about 10 s, typically) in order to trigger the alloying reactions between iron and zinc. The final microstructure of this kind of coatings is composed of a sequence of stratified Fe-Zn phase layers and its in-use properties are directly related to the phase distribution within the coating. The process parameters to be performed in industrial lines must therefore be optimized in order to obtain a successful coating microstructure with the minimum costs. The development of such a coating passes through different and complex reactions: the inhibition layer formation, the inhibition layer breakdown, the liquid zinc consumption and the iron enrichment of the solid coating. The kinetics accounting for these reactions must be studied and modelled separately in order to accurately control the evolution of the coating along the heat treatment performed in the industrial line. In the present work, the two first reactions were investigated in the case of Ti IF steel grades. The kinetics of the inhibition layer formation is extremely fast and has therefore not been investigated in detail. Concerning this reaction, the focus was given to the nature of this inhibition layer and to the mechanisms accounting for its formation. It has been found that the inhibition layer formed in typical baths for galvannealed coatings production is composed of a very thin layer of the Fe2Al5Znx phase (20-30 nm) on the steel surface and a thicker layer of the δ (FeZn7) phase (around 200 nm) on its top. As the steel strip enters the zinc bath, iron dissolution from the former into the latter leads to an iron supersaturation at the solid / liquid interface. As a result, a very thin layer of metastable Fe2Al5Znx nucleates on the steel surface favoured by preferential epitaxial relationships with ferrite. Subsequently, δ nucleates on the Fe2Al5Znx layer allowing the final microstructure of the inhibition layer to become thermodynamically stable. The effect of the bath aluminium content on the nature of this inhibiting structure has also been studied. As the bath aluminium content is lowered, the Fe2Al5Znx layer becomes discontinuous: the lower the bath aluminium content is, the higher the metastability of Fe2Al5Znx is and the less probable its nucleation on the steel surface is. The inhibition state is only transient and continued heat treatment will lead to the inhibition layer breakdown and the development of the further Fe-Zn alloying reactions. The breakdown mechanism, controlled by the diffusion of zinc towards the steel grain boundaries, can be explained using the Al-Fe-Zn ternary phase diagram and summarized in two steps: the disappearance of the Fe2Al5Znx layer at the inhibition layer / steel interface as a result of the enrichment of this interface in zinc, and the local nucleation of the Г (Fe3Zn10) phase at the steel grain boundaries, breaking the inhibition layer off, when the zinc concentration at these locations becomes high enough. The kinetics accounting for this reaction strongly depends on the Ti IF steel chemical composition and the bath aluminium content. On the one hand, it has been found that the effect of the steel chemical composition on the inhibition layer breakdown kinetics would be ruled by the competition between two opposite phenomena: the rate of zinc diffusion at the steel grain boundaries and the ability of the steel to accumulate the zinc atoms at these locations On the other hand, decreasing the bath aluminium content favours the discontinuity of Fe2Al5Znx, which accelerates the inhibition layer breakdown as zinc is expected to diffuse faster through δ than through Fe2Al5Znx