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Showing 1 to 20 of 50 for “"Alloy composition"”.
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Determining the effects of alloy composition, forging technique, and flux on the strength of forge welds
… of forge welds when made with different iron alloys, forge welding techniques, and fluxes was measured. The alloys used were 1018 steel, A36 steel and wrought iron. The forge welding techniques were the hydraulic press, the power hammer, and hand hammer. The fluxes were borax, fine silica …
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The influence of alloy composition and interfacial segregants on the fracture and fatigue of metal/ceramic interfaces
The use of multi-layered composites in the aircraft, automotive, and electronics industries is becoming more common as performance requirements exceed the capabilities of homogeneous materials. As a result, the need to assess their failure is critical. Diffusion bonded joints, thermal-barrier and …
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The Growth of Copper - Chromium Metastable Alloys by Bias Sputtering: Effect of Substrate Bias and Alloy Composition on Solubility and Morphology
Cu-Cr metastable alloys are interesting both from a basic science viewpoint (i.e., alloy theory for elements with very limited mutual liquid and solid solubilities) and from a technological viewpoint (i.e., "stainless" copper for corrosion and thin film circuit fabrications). Single phase Cu-Cr …
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The effect of alloy chemistry and strain rate on the Md30 temperature of metastable austenitic stainless steels
… stainless steels with small' variations in alloy composition. The study focuses mainly on the austenite stability with respect to alloy composition, rate of deformation and temperature. To achieve these objectives, uniaxial tensile tests at 0.3 true strain were performed at low and high …
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An x-ray study of the structure of K1-xRbxCy
… and K1-xRbxC24 represent quasi two-dimensional alloys interleaved by graphite hexagonal planes. We report extensive x-ray scattering investigations of the structural aspects of these compounds. In stage 1 K1-xRbxC8, we find that the interlayer separation exhibits a slight deviation from …
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Strain-balanced silicon-germanium materials for near IR photodetection in silicon-based optical interconnects
… superlattices grown on high quality compositionally graded buffers, or virtual substrates. make a complete range of alloy composition and biaxial strain combinations accessible. This structure is a unique way to achieve high quantum efficiency near IR photodetection for silicon-based …
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Solidification cracking resistance of high strength aluminum alloys
… in the manufacture of high strength aluminum alloys uneven cooling rates at different parts of the ingot cause thermal stresses. Due to these thermal stresses, cracks are initiated at the startup stage which may propagate as the stress elevates. Hence the evaluation of fracture toughness …
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Defect energies, band alignments, and charge carrier recombination in polycrystalline Cu(In,Ga)(Se,S)2 alloys
… thin films and the interrelationship with the alloy composition. Photoluminescence spectroscopy of investigated Cu-poor Cu(In,Ga)(Se,S)2 layers generally shows broad emission lines with the corresponding maxima shifting towards higher energies under decreasing temperature or under increasing …
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Steady State and Time-Resolved Cathodoluminescence Analysis of III-Nitride Semiconductors
… The idea here is to quantify the change in the alloy composition from the AlGaN layer of the structure and the carbon doping concentration from the GaN layer. The change in alloy composition is quantified by considering the change in emission wavelength while the carbon concentration is …
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Photoluminescence studies of carrier dynamics in (indium(x),aluminum(x)) gallium(1-x) arsenic/gallium arsenide quantum well structures
… luminescence is sensitive to well width, alloy composition, strain (in lattice-mismatched structures), and interface roughness. Continuous wave (cw) and time-resolved photoluminescence, and photoluminescence excitation (PLE) measurements were used to gain insight into the physics of GaAs …
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Nanocrystalline copper-tantalum composites
… x}$ (x = $\sim$5 to 20 atomic percent) alloys. These metastable alloys were produced using a plasma assisted physical vapor deposition (PAPVD) process which allowed ion bombardment during alloy deposition. Techniques used for structural and chemical analyses of these alloys include: …
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Oxidative dehydrogenation of ethane with carbon dioxide over iron-nickel nano-alloys supported on metal oxide overlayers
… Theory (DFT) study suggested that bimetallic alloys can have superior activity for CO2-activation compared to their monometallic counterparts [16]. Therefore, bimetallic alloys in conjunction with metal oxides may serve as stable bifunctional CO2-ODHE catalysts with enhanced CO2-activation …
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Cryomilling of Aluminum-based and Magnesium-based Metal Powders
… In this work, aluminum-rich and magnesium-rich alloys of varying composition are produced by cryomilling and characterized by x-ray diffraction. A novel consolidation process called high shear powder consolidation (HSPC) is used to densify as-received and as-milled powders with minimal growth. …
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Nanocrystalline Fe-Pt alloys: phase transformations, structure and magnetism
… and magnetic properties evolution in bulk Fe-Pt alloys composed of nanometer-sized grains. A comprehensive study of phase transformations and ordering in Fe-Pt alloys is performed by a combination of in-situ neutron powder diffraction and thermal analysis. The dependence of ordering processes on …
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On the electrolytic nature of molten aluminum and rare earth oxides
… primarily to signal interpretation during decomposition voltage measurement have hindered determination of Gibbs energy. An electrolytic cell method is proposed herein utilizing the sensitivity of large amplitude alternating current voltammetry, which enabled precise measurement of chemical …
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Piloting epitaxy with ellipsometry as an in-situ sensor technology
… high-quality crystalline films with a specified compositional profile as a function of film thickness. Although various epitaxial processes, such as molecular beam epitaxy or metal-organic chemical vapor deposition, have long been known to be capable of producing such films with mono-layer …
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Enhancing reactivity of aluminum-based structural energetic materials
… warhead casings through modi fication of alloy composition and casing geometry using controlled explosive initiation experiments. The study also explores e ffects of explosive end confi nement and impact induced fragment reactions. Transient and quasi-static pressure measurements, high …
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Developing spectroscopic ellipsometry to study II-VI and diluted magnetic semiconductors
… explained by the statistical fluctuation of the alloy composition.
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High-strength transformation-induced plasticity steels with reverted interlath austenite
… from diffusive to displacive; (ii) changing the alloy composition to promote diffusive transformation. To promote local displacive austenite reversion, the enrichment of austenite stabilizer at the martensite boundaries is introduced before reversion. To promote the diffusional transformation …
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On the application of machine-learning to the study of glass-formation in metallic systems: Prediction, optimisation, and characterisation of novel glassy alloys
… materials created by quenching a molten alloy mixture so quickly that crystalline phases do not have time to nucleate and grow, leaving a solid material with liquid-like structural disorder. This lack of crystalline ordering in MGs gives rise to a variety of desirable properties, …
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