Global ETD Search
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Showing 1 to 13 of 13 for “"BCC phase"”.
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Effect of Nonequilibrium Defects Due to Phase Transformation on Diffusion in Beta Zirconium
The effect of the hcp(--->)bcc phase transformation on the anomalous diffusion characteristics of bcc zirconium has been investigated in this study. ('113)Sn and ('59)Fe tracers were used to typify the diffusing nature of self- and fast-diffusing atoms. A differential measurement of diffusion in …
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Thermal vacancies in solid helium-3
… dependence of the x-ray lattice parameter. Bcc He 3 was studied for molar volumes ranging from 20.3 to 24.8 cm ; mole for which the melting temperatures range from 2.36 to 0.435K. It was found to contain about 0.5% thermal vacancies at melting, essentially independent of molar volume. A …
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Thermoelastic and dynamical properties of perfluoroethane
… orientational disorder. On cooling, a structural phase transformation from bcc crystal to triclinic crystal was verified at 103 K. The mean square momentum of fluorine atoms increases with temperature in the lower temperature solid phase but shows little temperature dependence in the higher …
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Gain effect waveguide optical amplifiers for Si microphotonics
… at 4 K, attributed to a metastable FCC or HCP phase. We showed the thermodynamically stable BCC crystal phase has PL emission lines at 1537 nm and 1550 nm, and metastable FCC and HCP crystal phases result in PL emission lines at 1542 nm and 1533 nm. Upconversion coefficient measurements on the …
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The potential for superlattice precipitate reinforcement in titanium-iron alloys
… featuring ordered B2 precipitates within a BCC matrix offers a promising possibility due to the potential synergistic benefits of a matrix with superlattice precipitates. The titanium-iron system is selected for this purpose, particularly as both are abundant elements, which should address …
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Deposition and characterization of magnetron sputtered BCC tantalum
… structures: 1) body center cubic (bcc) phase, characterized by high toughness and high ductility and 2) a tetragonal beta phase characterized by brittleness and a tendency to fail under stress. It was found in this work that the bcc Ta coatings on steel can be obtained reliably by …
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Metal oxide supported iron-nickel nano-alloys in the reverse water-gas shift reaction
… precursor nanoparticles, a mixture of fcc and bcc alloy phases was formed. An increase in Fe content increased the concentration of the bcc phase in the alloy. It was further demonstrated that the bcc surface of the Fe-Ni alloy activates CO2 while the fcc surface of the alloy appears to be …
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Oxidative dehydrogenation of ethane with carbon dioxide over iron-nickel nano-alloys supported on metal oxide overlayers
… to attain via impregnation as Ni and Fe oxide phases present in parallel make it challenging to extract the influence of the FexNiy alloy metallic composition [21]. This work aims to synthesize catalytically active metal oxide overlayers of a comparable pore structure, anchor FexNiy nano-alloys …
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Underlying deformation behavior of medium/high entropy alloys using advanced electron imaging and diffraction
… to extract local strain, orientation, and phase information. Taking advantage of recent advances in fast detectors, we develop a cepstral analysis workflow for cepstral STEM to improve planar faults identification. The 4D-STEM analysis is combined with conventional diffraction contrast TEM …
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Microstructure and properties of transition metal nitride and medium entropy alloy coatings
… but significantly influenced the microstructure, phase composition and mechanical properties. An evolution of microstructure from coarse to fine columnar grains with increasing bias voltage was identified, together with enhanced hardness and elastic modulus. Further, a transformation from a mixed …
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Investigation of the mechanical properties and phase stability of Ti-transition metal alloys using first-principle calculations
… classes depending on the fraction of monoboride phase in the Ti-matrix, which makes them useful for broad applications such as aerospace and biomedical fields. Based on the design principle of searching for Ti-monoboride ceramic phases with higher Young’s modulus, higher Pugh’s ratio, and lower …
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Electrodeposition of High Magnetostrictive Cobalt Iron Alloy Films for Smart Tags and Sensor Applications
… of Co0.7-0.75Fe0.3-0.25, targeting the (fcc+bcc)/bcc phase boundary, and using a novel chemistry and plating parameters to deposit films without being limited to line of sight' deposition1. To obtain the desired compositional range, a chemistry was selected to allow for a higher ratio of Co …
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Computational studies of solid state materials for practical applications
… with NiTi, Ni4Ti3, Ni3Ti, and Ni2Ti4Ox phases identified within the microstructure of the alloy. Density functional theory (DFT) was applied to predict the electronic structure of the NixTiy phases, including the band structure and site projected density of states. Ultraviolet …