Binary Alloys
Mostrando 1-12 de 41 artigos, teses e dissertações.
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1. Nb-Al Binary System: Reevaluation of the Solubility Limits of the (Nb), Nb3Al, Nb2Al and NbAl3 Phases at High Temperatures
In this work a re-investigation of the solubility limits of the (Nb), Nb3Al, Nb2Al and the Nb-rich side of the NbAl3 phases on the Nb-Al system is presented. Alloys in the binary fields ((Nb)+Nb3Al, Nb3Al+Nb2Al and Nb2Al+NbAl3) were arc-melted, and then equilibrated at 1000, 1200 and 1400 ºC. The phases were confirmed via X-ray powder diffractometry, and th
Mat. Res.. Publicado em: 25/11/2019
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2. Microstructure and Fracture of 50Mo-50Re Vacuum Brazed with Fe-Si-B Filler Metal
Microstructural evolution, interfacial reaction and fracture during vacuum brazing of 50Mo-50Re alloys using amorphous alloy Fe-5.6Si-2.6B(wt%) were investigated. A binary intermetallic compound, σ(Mo2Re3) formed as parallel contiguous layers in the diffusion zone. In addition, Fe from the braze alloy, in combination with dissolved Mo from the substrate, fo
Mat. Res.. Publicado em: 30/09/2019
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3. Effect of Sigma Phase Precipitated at 850 °C on Corrosion Behaviour of UNS S82441 Duplex Stainless Steel
ABSTRACT Duplex stainless steels (DSS) are alloys with binary microstructure consisting of ferrite (δ) and austenite (γ), combining high mechanical properties and corrosion resistance by pitting and stress corrosion, due to the two phases austenite/ferrite. However, the formation of secondary and intermetallic phases, during solidification processes, heat
Matéria (Rio J.). Publicado em: 16/09/2019
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4. Morphology and Phase Formation During the Solidification of Al-Cu-Si and Al-Ag-Cu Ternary Eutectic Systems
The microstructure of ternary alloys in the Al rich corner of the Al-Cu-Si and Al-Ag-Cu systems were analyzed in order to determine the solidification path in the different structural regions expected from the equilibrium phase diagram. The analysis was based on theoretical models developed in the literature for solidification of ternary eutectic system allo
Mat. Res.. Publicado em: 26/02/2018
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5. Nanoporous Gold Surface: An Efficient Platform for Hydrogen Evolution Reaction at Very Low Overpotential
A nanostructured porous gold film (NPGF) was fabricated onto a gold electrode surface by an electrochemical approach involving anodization followed by electrochemical reduction in absence of binary alloys, templates and chemical reducing agents. The electrocatalytic activity of the as-fabricated electrocatalyst was examined towards hydrogen evolution reactio
J. Braz. Chem. Soc.. Publicado em: 2018-02
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6. Analysis of Spinodal Decomposition in Al-Zn and Al-Zn-Cu Alloys Using the Nonlinear Cahn-Hilliard Equation
The phase field model based on the nonlinear Cahn-Hilliard equation was applied to analyze the spinodal decomposition process in Al-Zn and Al-Zn-Cu alloys. Partial differential equations were solved using the explicit finite difference method for the Al- 20, and 35 at. % Zn alloys aged at temperatures between 25 and 100 °C for times from 10 s to 2000 s and
Mat. Res.. Publicado em: 20/03/2017
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7. Platinum-Based Alloys: Investigation of the Effect of Impurities Content on Creep Rate, Rupture Time and Relative Elongation at High Temperatures
This paper presents the results of research of the effect of impurities content on high-temperature resistance of selected platinum alloys. Alloys of following systems were investigated: Pt-Rh, Pt-Rh-Pd, Pt-Rh-Pd-Ru and Pt-Rh-Pd-Ir-Au. Universal device for tensile testing of materials at high temperatures was used for examination. Investigations were carried
Mat. Res.. Publicado em: 05/01/2017
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8. Predicting Secondary-Dendrite Arm Spacing of the Al-4.5wt%Cu Alloy During Unidirectional Solidification
Mechanical properties and performance of metallic materials depend on their microstructures. In order to develop engineering materials that match prescribed criteria and to enable design with multifunctional materials, it is essential to be able to predict their microstructural patterns, such as size, shape, and spacing of the dendritic structures observed i
Mat. Res.. Publicado em: 24/11/2016
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9. Interconnection between microstructure and microhardness of directionally solidified binary Al-6wt.%Cu and multicomponent Al-6wt.%Cu-8wt.%Si alloys
Um estudo experimental foi realizado para avaliar a evolução da microestrutura e da microdureza nas ligas binária Al-6% Cu e multicomponente Al-6%Cu-8%Si solidificadas direcionalmente e o efeito do elemento de liga Si. Para tanto, espécimes das ligas Al-6%Cu e Al-6%Cu-8%Si foram preparadas e solidificadas em con dições transitórias de extração de ca
An. Acad. Bras. Ciênc.. Publicado em: 31/05/2016
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10. Composition, Elastic Property and Packing Efficiency Predictions for Bulk Metallic Glasses in Binary, Ternary and Quaternary Systems
The results of database based on the efficiency packed model for metallic glasses. The database contains the atomic radii information as well as elastic properties of the most commonly used alloying elements, permitting composition, packing efficiency and elastic property predictions to be made for binary, ternary and quaternary bulk metallic glasses. Twenty
Mat. Res.. Publicado em: 08/03/2016
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11. Determination of Microstructure, Mechanical, Electrical and Thermal Properties of The Directionally Solidified Al-Si-Co Ternary Alloy
In this work, Al-12.6Si-2Co (wt.%) ternary alloy of near eutectic composition was directionally solidified at a constant temperature gradient (G=7.60 K/mm) in a wide range of growth rates (V=8.35-166.30 µm/s) using by Bridgman type growth apparatus. Flake spacing (λ), microhardness (HV), tensile stress (σ) and electrical resistivity (ρ) were measured fro
Mat. Res.. Publicado em: 26/02/2016
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12. On the Natural Convection in the Columnar to Equiaxed Transition in Directionally Solidified Aluminum-based Binary and Multicomponent Alloys
In order to investigate the effect of natural convection in columnar to equiaxed transition (CET), Al-3.0wt.%Cu and Al-3.0wt.%Cu-5.5wt.%Si alloys ingots were obtained during the transient horizontal directional solidification (THDS). Aiming to analyze the effect of superheat in the formation of the macrostructure in ternary Al-Cu-Si alloy, the experiments we
Mat. Res.. Publicado em: 04/12/2015