Academic literature on the topic 'Allotropic transformations'
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Journal articles on the topic "Allotropic transformations"
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Jung, Hyun Young, Sung Mi Jung, Dong Won Kim, and Yung Joon Jung. "Inter-allotropic transformations in the heterogeneous carbon nanotube networks." Nanoscale 9, no. 3 (2017): 1014–21. http://dx.doi.org/10.1039/c6nr08393e.
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El-Bitar, Taher, Eman El-Shenawy, and Maha El-Meligy. "Physical Simulation of Thermo-Mechanical Processing of Ferritic-Bainitic Dual Phase (FBDP) Steel." Materials Science Forum 879 (November 2016): 495–501. http://dx.doi.org/10.4028/www.scientific.net/msf.879.495.
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The present work is dealing with a physical simulation of thermo-mechanical processing of ferritic-bainitic dual phase (FBDP) steel alloy containing 0.1% C, 0.3% Si, 0.9% Mn and 0.7% Cr. The microstructure changes and allotropic transformations during thermo-mechanical simulation are investigated. A series of heating – cooling cycles to detect the critical and allotropic transformation temperature by dilatation were carried out on the thermo-mechanical simulator (Gleeble 3500). On the other hand, five – consecutive hits were used during the physical simulation of hot rolling process. Two hits were representing the roughening stage followed by three ones representing finish rolling. Holding at 500°C for 5, 7, 10, 12 and 15 min. after last hit has been applied and then followed by air cooling. Dilation curves appear that Ac1= 766 °C, while Ac3 was detected as 883 °C. Baintic allotropic transformation temperatures were clearly noticed as 618 °C for Bs and 542 °C for Bf. The recrystallization temperature was also detected as 1035 °C. Holding for 5-7 min. at 500 °C was concluded as the optimum for creation a bainite volume fraction. Rough hot deformation a higher temperature above the recrystallization temperature is essential, where no strain hardening and possibility for achieving high strains without excessive loads. Finishing deformation at temperature lower than Tr would create fine bainitic structure. The flow curve of the steel ensures continuous strain hardening. The strain hardening rate (σf/ε) was directly proportional to temperature difference from pass to pass.
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Gyöngyösi, Szilvia, Anita Tóth, and Péter Barkóczy. "Simulation of Phase Transformations Driven by Short Range Diffusion by Cellular Automaton." Materials Science Forum 659 (September 2010): 405–10. http://dx.doi.org/10.4028/www.scientific.net/msf.659.405.
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The same property of the phase transformations driven by short range diffusion (recrystallization, allotropic transformation, grain coarsening) is that the movements of the grain or the phase boundaries take place by atomic jumps through the boundaries. The probability (frequency) of these jumps depends on only on the energy state of the closenear neighborhood of the atoms. In the operation of cellular automata Consequently, only the closenear neighborhood of the cells is taken into account in the operation of the cellular automaton. This similarity makes applicable the cellular automaton applicable to simulate the aforementioned phase transformation processes. A condition (rule) of the movement of grain and phase boundaries is introduced, which makes it possible to simulate all the all mentioned phase transformation by the same automatona.
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Zocco, T. G., D. S. Schwartz, and J. Park. "Investigation of plutonium allotropic phase transformations through differential scanning calorimetry." Journal of Nuclear Materials 353, no. 1-2 (2006): 119–26. http://dx.doi.org/10.1016/j.jnucmat.2006.02.085.
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Gileta, Viktor, and Anatoly Beznedelnyy. "The mechanism of wearing of the hard alloy tool under ultrasonic reinforcing finishing treatment." MATEC Web of Conferences 224 (2018): 01008. http://dx.doi.org/10.1051/matecconf/201822401008.
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The working capacity of indenters prepared from hard alloy VK8 under conditions of reinforcing finishing treatment by ultrasonic tools was investigated. It was found that under normal treatment conditions, normal wear of the hard alloy takes place. An electron microscopic study of the morphology of the surface of the wear area and its state after the etching of cobalt (Co) using replicas was performed. X-ray microanalysis of the wear area was performed. No obvious traces of adhesive, diffusion, abrasive wear were detected. It was shown that the deterioration of the hard alloy tool VK8 mainly occurs as a result of fatigue failure, which leads in the investigated speed range of the part 10...120 m/min to the precipitation of individual carbide grains and whole groups of them. The non-linear nature of the wear-velocity curve is due to allotropic transformations of cobalt. It was found that at cobalt speeds of 10...50 m/min, the first allotropic transformation from the initial β-Co state to α-Co occurs, and then the second partial allotropic conversion of α-Co to β-Co occurs at a velocity of more than 50 m/min. The presence of a β-Co phase, which is more brittle, leads to an intensification of wear. The WC-WC boundaries and the deformation of WC carbides are not responsible for the formation of the wear surface microrelief and the integral wear of the carbide tool.
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ABRUDEANU, MARIOARA, GABRIEL NEACȘU, ANDREEA ELENA ROȘU, et al. "The influence of thermal shock t high temperature on Zy-4 alloy." Journal of Engineering Sciences and Innovation 5, no. 1 (2020): 21–32. http://dx.doi.org/10.56958/jesi.2020.5.1.3.
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"Zy-4 alloy is a basic material in the construction of the current generation nuclear reactors. Due to the diffusion processes and the chemical reactions that take place, the corrosion in air at high temperatures of the zircaloy-4 alloy determines the appearance of new phases and constituents and the stabilization of the alpha phase at high temperatures, above the allotropic transformation temperature. The paper presents the structural transformations that take place in the alloy following the oxidation under thermal shocks applied in the range 600-1500 ° C, in correlation with the chemical composition, hardness and thermal transfer properties. "
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Seelam, Uma M. R., Gagik Barkhordarian, and Challapalli Suryanarayana. "Is there a hexagonal-close-packed (hcp) → face-centered-cubic (fcc) allotropic transformation in mechanically milled Group IVB elements?" Journal of Materials Research 24, no. 11 (2009): 3454–61. http://dx.doi.org/10.1557/jmr.2009.0423.
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Allotropic hexagonal-close-packed (hcp) → face-centered-cubic (fcc) transformations were reported in Group IVB elements titanium (Ti), zirconium (Zr), and hafnium (Hf) subjected to mechanical milling in a high-energy SPEX shaker mill. Although the transformation was observed in powders milled under regular conditions, no such phase transformation was observed when the powders were milled in an ultrahigh purity environment by placing the powder in a milling container under a high-purity argon atmosphere, which was in turn placed in an argon-filled glove box for milling. From a critical analysis of the results, it was concluded that the hcp → fcc phase transformation was, at least partially, due to pick-up of interstitial impurities by the powder during milling of these powders to the nanocrystalline state.
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Sokołowski, M., A. Sokołowska, M. Wronikowski, and T. Kosik. "Allotropic phase transformations induced by ultraviolet power laser irradiation of graphite." Journal of Materials Science 25, no. 1 (1990): 379–83. http://dx.doi.org/10.1007/bf00714043.
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Straumal, Boris, Askar Kilmametov, Andrey Mazilkin, et al. "DIFFUSIVE AND DISPLACIVE PHASE TRANSFORMATIONS UNDER HIGH PRESSURE TORSION." Acta Metallurgica Slovaca 25, no. 4 (2019): 230. http://dx.doi.org/10.12776/ams.v25i4.1368.
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<p class="AMSmaintext"><span lang="EN-GB">Severe plastic deformation (SPD) can induce various phase transformations. After a certain strain, the dynamic equilibrium establishes between defects production by an external force and their relaxation (annihilation). The grain size, hardness, phase composition etc. in this steady-state does not depend on the initial state of a material and is, therefore, equifinal. In this review we discuss the competition between precipitation and dissolution of precipitates, amorphization and (nano)crystallization, SPD-induced accelerated mass-transfer, allotropic and martensitic transitions and formation of grain boundary phases.</span></p>
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Edalati, Kaveh, Shoichi Toh, Yoshifumi Ikoma, and Zenji Horita. "Plastic deformation and allotropic phase transformations in zirconia ceramics during high-pressure torsion." Scripta Materialia 65, no. 11 (2011): 974–77. http://dx.doi.org/10.1016/j.scriptamat.2011.08.024.
Full textDissertations / Theses on the topic "Allotropic transformations"
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Ewh, Ashley Elizabeth. "Effects of Allotropic Transformations on Interdiffusion Behavior in Binary Systems." Master's thesis, University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5201.
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Diffusion plays a significant role in most materials systems by controlling microstructural development. Consequently, the overall properties of a material can be largely dependent upon diffusion. This study investigated the interdiffusion behavior of three binary systems, namely, Mo-Zr, Fe-Mo, and Fe-Zr. The main interest in these particular metals is for application in nuclear fuel assemblies. Nuclear fuel plates generally consist of two main components which are the fuel and the cladding. Due to diffusional interactions that can occur between these two components, a third is sometimes added between the fuel and cladding to serve as a diffusion barrier layer. Fe, Mo, and Zr can act as either cladding or barrier layer constituents and both Mo and Zr also serve as alloying additions in uranium based metallic fuels. Therefore, a fundamental understanding of the diffusional interactions in these systems is critical in predicting the performance and lifetime of these fuels. In order to study this diffusion behavior, a series of solid-to-solid diffusion couples were assembled between Fe, Mo, and Zr. These couples were then diffusion annealed isothermally for various predetermined times over a range of temperatures, including some both above and below the allotropic transformation temperatures for Fe and Zr. Following the diffusion anneal, the couples were water quenched, cross-sectioned, and prepared for microstructural and compositional characterization. A combination of scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and electron probe microanalysis (EPMA) were used to obtain micrographs showing the microstructure and to collect compositional data for identifying intermediate phases and determining concentration profiles across the interdiffusion zone. Based on this characterization, the phases that developed in the diffusion zones were identified. In the Mo-Zr system, a large Zr solid solution layer developed in the couples annealed at and above 850[degrees]C and a thin (~1-2 [micro]m) layer of Mo2Zr formed in all couples. Growth constants and concentration dependent interdiffusion coefficients were calculated for the Mo2Zr and Zr solid solution phases, respectively. In the Fe-Mo system, both the [lambda]-Fe2Mo and [micro]-Fe7Mo6 phases were observed in couples annealed at 900[degrees]C and below while [micro]-Fe7Mo6 and [alpha]-Fe solid solution layers were observed in couples annealed above 900[degrees]C. The relevant growth constants and activation energies for growth were calculated. In the Fe-Zr system, the couple annealed at 750[degrees]C developed an FeZr2 and an FeZr3 layer while the couple annealed at 850[degrees]C developed an Fe2Zr and Fe23Zr6 layer in the diffusion zone. The results of this analysis were then compared to available information from literature and the corresponding binary phase diagrams for each system. The results are discussed with respect to the effects of the allotropic transformations of Fe and Zr on the interdiffusion behavior in these systems.<br>ID: 031001410; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Adviser: Yongho Sohn.; Title from PDF title page (viewed June 13, 2013).; Thesis (M.S.M.S.E.)--University of Central Florida, 2012.; Includes bibliographical references (p. 84-89).<br>M.S.M.S.E.<br>Masters<br>Materials Science Engineering<br>Engineering and Computer Science<br>Materials Science and Engineering; Accelerated BS to MS
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Bruzy, Nicolas. "Couplage entre plasticité et transformation de phase dans le Fer : Étude par corrélation d’images et modélisation." Thesis, Ecole centrale de Nantes, 2018. http://www.theses.fr/2018ECDN0056/document.
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Les propriétés mécaniques des alliages de fer sont largement conditionnées par leur microstructure et la population de défauts locaux qu’elle contient. Comme il s'agit d'un moment de forte interaction entre ces deux éléments, l'étude des transformations α-γ et γ-α du fer mérite une attention particulière. Outre le passage d'une structure cristalline cubique centrée à une structure cubique faces centrées – donc de compacités différentes –,elles sont associées à une réduction des paramètres de maille. Le changement de volume correspondant est responsable de déformations mécaniques locales autour des sites de germination. La technique de corrélation d'images numériques(CIN) s'est montrée fiable pour ce qui est de calculer des champs cinématiques à l'échelle de quelques grains. Dans ce travail, elle est adaptée à la capture de localisations de la déformation pendant les transformations allotropiques. Un banc expérimental est conçu pour obtenir des images haute résolution avec un contrôle fin des sollicitations thermiques. Des essais de validation sont d'abord effectués sur du fer industriel. Puis des échantillons de fer haute pureté sont ensuite soumis à des cycles de transformation α-γ-α et les champs de déformation correspondant sont calculés par CIN. Associés à l'acquisition des orientations initiales et finales, ils sont utilisés pour valider les mécanismes de transformation proposés dans la littérature. En parallèle, un modèle, écrit en petites déformations, est construit en incorporant des composants liés à la transformation dans une fonctionnelle dont les conditions de stationnarité sont équivalentes au problème thermomécanique à résoudre. Les incréments des variables internes, incluant glissements plastiques et fractions volumique transformées, sont obtenus en minimisant cette fonctionnelle<br>Mechanical properties of iron-based alloys are largely conditioned by their microstructure and the population of local defects inside this microstructure. As it is a moment of massive interplay between these two elements, the study of the α-γ and γ-α transformations in iron is of particular interest. Besides a change from a body-centered cubic to a face-centered cubic crystal structure – and thus a change in compacity –, they lead to a lattice parameter reduction. The corresponding change in volume is responsible for local mechanical deformations around transformation sites. Digital Image Correlation (DIC) technique has been proven reliable to compute kinematic fields at the scale of a few grains. In the present work, an adaptation of this technique to the observation of strain localizations induced by the formation of a new phase is proposed. A home-made device is designed to obtain high resolution images and to control heating and cooling. Tests are first conducted on industrial iron to assess the viability of the procedure. High-purity iron samples are then submitted to α-γ-α transformation cycles and the associated strain fields are computed. In combination with the acquisition of initial and final orientations they are used to validate transformation mechanisms proposed in the literature. In parallel, a model, written under the small strain format, is built by incorporating transformation related components into a power functional whose stationarity conditions are equivalent to the thermomechanical problem. In accordance with variational principles, the evolution of internal variables,including plastic slip increments and fraction of the material locally transformed, are computed through the minimization of the functional
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Cousins, Christopher Stanley George. "Inner elasticity and the higher-order elasticity of some diamond and graphite allotropes." Thesis, University of Exeter, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342008.
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Muniz, Andre R. "Computational analysis of structural transformations in carbon nanostructures induced by hydrogenation." 2011. https://scholarworks.umass.edu/dissertations/AAI3465058.
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Carbon nanomaterials, such as carbon nanotubes and graphene, have attracted significant interest over the past several years due to their outstanding and unusual combination of physical properties. These properties can be modified in a controllable way by chemical functionalization in order to enable specific technological applications. One example is hydrogenation, achieved by the exposure of these materials to a source of atomic hydrogen. This process has been considered for hydrogen storage purposes and for the control of the band gap of these materials for applications in carbon-based electronics. Hydrogen atoms are chemisorbed onto the surface of these materials, introducing sp3-hybridized C-C bonds in a structure originally formed by delocalized sp2 C-C bonding. This bonding transition causes severe structural and morphological changes to the graphene layers/walls. Also, it has been demonstrated that the exposure of multi-walled carbon nanotubes (MWCNTs) to a H2 plasma leads to the formation of diamond nanocrystals embedded within the nanotube walls. This thesis presents a computational analysis of the effects of hydrogen chemisorption on the structure and morphology of graphene and single-walled carbon nanotubes (SWCNTs), as well as of the different nanostructures that can be generated upon formation of inter-shell and inter-layer sp 3 C-C bonds in MWCNTs and few-layer graphene (FLG), respectively. The analysis is based on a synergistic combination of atomic-scale modeling tools, including first-principles density functional theory (DFT) calculations and classical molecular-dynamics (MD) and Monte Carlo (MC) simulations. The results demonstrate that SWCNTs and graphene swell upon hydrogenation and provide interpretations to experiments reported in the literature; this swelling depends strongly on the hydrogen surface coverage. A MC/MD-based compositional relaxation procedure generates configurations whose arrangements of H atoms are in excellent agreement with experimental observations. Detailed structural analysis of the hydrogenated surfaces is carried out, providing information which cannot be extracted easily from conventional experimental techniques. The findings of the analysis are used to explain the limitations on the maximum H storage capacity of SWCNT bundles upon their exposure to an atomic H flux. Furthermore, it is demonstrated that the structures resulting from formation of inter-shell or inter-layer C-C bonds are stable and provide seeds for the nucleation of crystalline carbon phases embedded into the shells and layers of the MWCNT and FLG structures, respectively. The key parameter that determines the type and size of the generated nanocrystals is the chiral-angle difference between adjacent layers/walls in the original structure. A novel type of carbon structure, consisting of fullerene-like caged configurations embedded within adjacent graphene layers, has been discovered for the case where the graphene layers are rotated with respect to each other; interestingly, one class of these structures retains the unique and desired electronic properties of single-layer graphene.
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Moses, Julianne Ives. "I. Phase Transformations and the Spectral Reflectance of Solid Sulfur: Possible Metastable Sulfur Allotropes on Io's Surface. II. Photochemistry and Aerosol Formation in Neptune's Atmosphere." Thesis, 1991. https://thesis.library.caltech.edu/2993/4/Moses_ji_1991.pdf.
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<p>This thesis consists of two independent papers:</p>
<p>PAPER I:</p>
<p>The spectral reflectance of elemental sulfur is examined in a set of laboratory experiments to determine the factors that affect the transformation rate of monoclinic (β) sulfur and various other sulfur allotropes into orthorhombic (α) sulfur. The laboratory data have implications for the spectral variation and physical behavior of freshly solidified sulfur, if any exists, on Jupiter's satellite Io. Depending on its thermal history, molten sulfur on Io would initially solidify into a glassy solid or a monoclinic crystalline lattice; these forms might contain polymeric sulfur molecules as well as the more abundant S<sub>8</sub> molecules. If freshly frozen sulfur on Io could lose heat rapidly and approach ambient dayside Io temperatures within several hours, then some of the metastable sulfur allotropes could be maintained on Io virtually indefinitely. Small droplets of sulfur ejected during plume eruptions might cool quickly enough to preserve these allotropes, but sulfur in large volcanic flows or lakes would probably remain warm long enough for phase transformations to proceed at a visible rate.</p>
<p>PAPER II:</p>
<p>Photodissociation of methane at high levels in Neptune's atmosphere leads to the production of more complex hydrocarbon species such as ethane, acetylene, methylacetylene, propane, diacetylene, ethylacetylene, and butane. These gases diffuse to the lower stratosphere where temperatures are low enough to allow all seven of the aforementioned species to condense. Particle formation may not occur readily, however, as the vapor species become supersaturated. We present a theoretical analysis of particle formation mechanisms at conditions relevant to Neptune's troposphere and stratosphere and show that hydrocarbon nucleation is very inefficient under Neptunian conditions: saturation ratios much greater than unity are required for aerosol formation by either heterogeneous, ion-induced, or homogeneous nucleation. Thus, stratospheric hazes may form far below their saturation levels. We compare nucleation models with detailed atmospheric photochemical models in order to place realistic constraints on the altitude levels at which we expect hydrocarbon hazes or clouds to form on Neptune.</p>
Conference papers on the topic "Allotropic transformations"
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Li, Y. L., C. L. Ma, and H. Zhang. "Crystallographic Orientation Evolution in NbSS-Nb5Si3 Eutectic Alloys by EBSD Analyses." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-95309.
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The progresses in high temperature materials encourage the development of turbine engine in terms of thrust and efficiency. Ni-based superalloys, which are predominant in elevated temperature application, have limited potential to raise serving temperature. In-situ composites, such as Cr-Cr3Si, NiAl-Cr and Nb-Nb5Si3 eutectic alloys, consisting of a ductile metallic phase and a hard intermetallic phase, are attractive candidates to replace Ni-based superalloys. The microstructure and mechanical properties of these in-situ composites are widely investigated. However, little work is focused on crystallography of in-situ composites, except for preferred growth direction and crystallographic orientation relationship. In this paper, Nb-Si-Mo-based alloys were fabricated by non-consumable arc melting, and then were directionally solidified in an optical floating zone (OFZ) melting furnace. The crystallographic orientation evolutions in Nb-Nb5Si3 eutectic alloy are studied by electron back-scattered diffraction (EBSD) analyses. First, the effect of solidification condition on crystallographic orientation is examined. The as-cast alloy displays cellular microstructure. The Nb phase shows different crystallographic orientations in different cells, while the Nb5Si3 phase shows similar crystallographic orientation in a number of cells. In directionally solidified alloys, when growth rate is 5mm/h without seed rod rotation, the grain sizes of Nb and Nb5Si3 are both several millimeter. As growth rate rises or seed rod rotates, the grain size of Nb decreases much more drastically than that of Nb5Si3. Thus, solidification condition is supposed to influence nucleation of the Nb phase rather than the Nb5Si3 phase. Second, the effect of annealing on crystallographic orientation is studied. The Nb5Si3 has three allotropic phases. The allotropic phase transformations occur through annealing, during which the Nb5Si3 grain size decreases.
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Lee, Pei-Tzu, Wan-Zhen Hsieh, Cheng-Yu Lee, C. R. Kao, and Cheng-En Ho. "White X-ray Nanodiffraction Study of Allotropic Phase Transformation of Hexagonal- into Monoclinic-Cu6Sn5." In 2021 International Conference on Electronics Packaging (ICEP). IEEE, 2021. http://dx.doi.org/10.23919/icep51988.2021.9451997.
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Шмаков, Игорь Александрович, and Владимир Иванович Иордан. "ANALYSIS OF PHASE FORMATION IN SH-SYNTHESIS OF TITANIUM ALUMINIDES IN MATRIX HOMOGENEOUS COMPOSITIONS OF Al@TI NANOPARTICLES WITH A “CORE-SHELL” STRUCTURE." In Инновационные исследования: проблемы внедрения результатов и направления развития: сборник статей международной на учной конференции (Санкт Петербург, Ноябрь 2024). Crossref, 2025. https://doi.org/10.58351/241105.2024.45.17.003.
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В работе проводится анализ температурной динамики и фазообразования в модельной матричной композиции однородного состава из наночастиц Al@Ti с композитной структурой «ядро-оболочка» (Al - в ядре, Ti - в оболочке), в которой инициируется СВ-синтез алюминидов титана. В стационарном режиме СВС с температурой горения 1550 К образуется фаза TiAl и происходит аллотропное превращение α-Ti в b-Ti The paper analyzes the temperature dynamics and phase formation in a model matrix homogeneous composition of Al@Ti nanoparticles with a core-shell composite structure (Al - core, Ti - shell), in which the SH-synthesis of titanium aluminides is initiated. In the stationary SHS mode with a combustion temperature of 1550 K, the Ti3Al phase is formed and the allotropic transformation of α-Ti into b-Ti occurs
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Hollis, Kendall J., Dustin R. Cummins, Sven C. Vogel, Donald W. Brown, and David E. Dombrowski. "Characterization of Plasma Sprayed Zirconium Coatings on Uranium Alloy Using Neutron Diffraction." In ITSC2018, edited by F. Azarmi, K. Balani, H. Li, et al. ASM International, 2018. http://dx.doi.org/10.31399/asm.cp.itsc2018p0299.
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Abstract Plasma sprayed zirconium (Zr) metal coatings onto uranium-molybdenum (U-Mo) alloy nuclear reactor fuel foils act as a diffusion barrier between the fuel and the aluminum fuel cladding. Neutron diffraction was performed to investigate the crystallographic phase composition, crystal orientations and lattice parameters of the plasma sprayed Zr and the U-Mo substrate. The neutron diffraction results show that the plasma sprayed Zr coating is crystalline, phase pure (alpha-Zr) and has preferred crystalline orientation likely due to directional solidification. Also, there is a slight (~0.01 Å for a direction and ~0.016 Å for c direction) increase in the plasma sprayed Zr lattice parameter indicating oxygen in the lattice and some residual thermo-mechanical strain. There is little or no modification of the underlying U-Mo following plasma spraying. In particular, there is no detectable allotropic transformation of the starting gamma-U (body-centered cubic) to alpha-U (orthorhombic). The unique neutron diffraction capabilities at LANL are well suited for nuclear fuel characterization offering distinct advantages over conventional X-ray diffraction and destructive metallography.
Reports on the topic "Allotropic transformations"
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Lopez, P. C., J. R. Cost, and K. M. Axler. Martensitic nature of {delta} {yields} {gamma} allotropic transformation in plutonium. Office of Scientific and Technical Information (OSTI), 1996. http://dx.doi.org/10.2172/378831.
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