Effect of chemical composition on the microstructure, hardness and electrical conductivity profiles of the Bi-Ge-In alloys

In this study, the microstructure, hardness, and electrical properties of selected ternary Bi-Ge-In alloys were investigated. Isothermal sections of the Bi-Ge-In system at 25, 200, and 300 ° C were extrapolated using optimized thermodynamic parameters from the literature. The used experimental techniques include optical microscopy, X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and energy dispersion spectrometry (EDS), Brinell hardness, and electrical conductivity measurements. The results of EDS phase composition analysis were compared with the calculated isothermal sections and a good overall agreement was reached. The results of the XRD were also in line with the predicted phase balance. By using ANOVA analysis and experimental results of Brinell hardness and electrical conductivity, a mathematical model was suggested for the calculation of these properties along with all composition ranges. The appropriated mathematical model was subsequently used for the prediction of hardness and electrical conductivity throughout the whole composition range

Mechanical and electrical properties of the Bi-Ge-Sn alloys

Mechanical and electrical properties of the ternary Bi-Ge-Sn alloys were investigated in this study. Calculation of isothermal section at 200, 300, and 25 ºC was carried out by using optimized thermodynamic parameters for the constitutive binary systems. Microstructures of alloys were observed by using optical microscopy and scanning electron microscopy (SEM). Phases in microstructures have been detected by X-ray diffraction (XRD) analysis and compositions of the phase by energy dispersive spectrometry (EDS). EDS results were compared with the predicted isothermal section at 200 and 300 ºC, and good agreement has been reached between them. The Brinell hardness and electrical conductivity of selected alloys were measured.  Through ANOVA analysis and application of the obtained results, an appropriate mathematical model is proposed for every composition of alloys. By using the appropriated mathematical model for Brinell hardness and electrical conductivity, isolines for those properties were presented

Phase transformations and thermal conductivity of the In-Ag alloys

Phase transformations and thermal conductivity of three In-Ag alloys with 5, 15, and 45 wt.% of Ag were experimentally investigated in the present work. Phase transition temperatures were measured using differential scanning calorimetry (DSC). DSC heating scans were compared with the equilibrium and non-equilibrium solidification paths, calculated by using optimized thermodynamic parameters from literature and calculation of phase diagrams (CALPHAD) method.  The flash method was employed for the determination of thermal diffusivity and thermal conductivity of the investigated alloys in the temperature range from 25 to 100 °C. It has been found that an increase in silver content does not lead to an increase in the thermal conductivity of the investigated alloys. Thermal conductivities for all three investigated In-Ag alloys slightly decrease with temperature increasing

Au-Ni nanoparticles: Phase diagram prediction, synthesis, characterization, and thermal stability

The Au-Ni nanoparticles (NPs) were prepared by oleylamine solvothermal synthesis from metal precursors. The Au-Ni phase diagram prediction respecting the particle size was calculated by the CALPHAD method. The hydrodynamic size of the AuNi NPs in a nonpolar organic solvent was measured by the dynamic light scattering (DLS) method. The average hydrodynamic sizes of the nanoparticle samples were between 18 and 25 nm. The metallic composition of the AuNi NP samples was obtained by inductively-coupled plasma atomic emission spectroscopy (ICP-OES). The metallic fraction inside AuNi NPs was varied Au-(30-70)wt%Ni. The steric alkylamine stabilization was observed. The individual AuNi NPs were investigated by transmission electron microscopy (TEM). The dry nanopowder was also studied. The structures of the aggregated samples were investigated by scanning electron microscopy (SEM). The AuNi NPs reveal randomly mixed face-centered cubic (FCC) crystal lattices. The phase transformations were studied under inert gas and air. The samples were studied by differential scanning calorimetry (DSC).Nanočástice Au-Ni (NPs) byly připraveny solvotermální syntézou z kovových prekurzorů. Predikce fázového diagramu Au-Ni s ohledem na velikost částic byla vypočítána metodou CALPHAD. Hydrodynamická velikost AuNi NP v nepolárním organickém rozpouštědle byla měřena metodou dynamického rozptylu světla (DLS). Průměrné hydrodynamické velikosti vzorků nanočástic byly mezi 18 a 25 nm. Chemické složení kovů vzorků AuNi NP bylo získáno indukčně vázanou plazmovou atomovou emisní spektroskopií (ICP-OES). Kovová frakce uvnitř AuNi NP byla různá v rozmězí Au-(30-70hm%)Ni. Byla pozorována sterická stabilizace alkylaminem. Jednotlivé NP AuNi byly zkoumány tramsmisní elektronovou mikroskopií (TEM). Také byl zkoumán suchý nanoprášek. Struktury agregovaných vzorků byly zkoumány pomocí skenovací elektronové mikroskopie (SEM). AuNi nanočástice vykazovaly krystalovou mřížku náhodně smíšeného tuhého roztoku (FCC). Fázové transformace byly studovány pod inertním plynem a na vzduchu. Vzorky byly také studovány diferenční skenovací kalorimetrií (DSC)

Mechanical and electrical properties of ternary Ag-Bi-Ga system at 250 °C

This paper presents a comparative review of the experimental and thermodynamic assessment of a ternary Ag-Bi-Ga system. An isothermal section at 250 °C was calculated using optimized thermodynamic data for the constitutive binaries. Microstructures and phase compositions of studied alloys were analyzed by scanning electron microscopy in combination with energy dispersive spectrometry and X-ray powder diffraction technique. The obtained experimental results were found to support the predicted phase equilibria rather well. The hardness of alloys from three vertical sections (Bi-AgGa, Ag-BiGa, and Ga-AgBi) was determined using Brinell hardness test while the hardness of the individual identified phases was determined using Vickers microhardness test. Additional electrical conductivity measurements were carried out on the same alloy samples. Based on the experimentally obtained results iso-lines of Brinell hardness and electrical conductivity for the entire compositional range were calculated

Effect of chemical composition on the microstructure, hardness and electrical conductivity profiles of the Bi-Ge-In alloys

© 2020, Association of Metallurgical Engineers of Serbia. All rights reserved. In this study, the microstructure, hardness, and electrical properties of selected ternary Bi-Ge-In alloys were investigated. Isothermal sections of the Bi-Ge-In system at 25, 200, and 300 °C were extrapolated using optimized thermodynamic parameters from the literature. The used experimental techniques include optical microscopy, X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and energy dispersion spectrometry (EDS), Brinell hardness, and electrical conductivity measurements. The results of EDS phase composition analysis were compared with the calculated isothermal sections and a good overall agreement was reached. The results of the XRD were also in line with the predicted phase balance. By using ANOVA analysis and experimental results of Brinell hardness and electrical conductivity, a mathematical model was suggested for the calculation of these properties along with all composition ranges. The appropriated mathematical model was subsequently used for the prediction of hardness and electrical conductivity throughout the whole composition range

Effect of chemical composition on the microstructure, hardness and electrical conductivity profiles of the Ag-Bi-Ge Alloys

© 2019 Universidade Federal de Sao Carlos. All rights reserved. Microstructure, hardness and electrical properties of the selected ternary Ag-Bi-Ge alloys were investigated in this study. Isothermal sections of the Ag-Bi-Ge system at 25, 100 and 500 °C have been extrapolated using optimized thermodynamic parameters from literature and experimentally investigated. Performed experiments were optical microscopy, scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS), X-ray powder diffraction (XRD), hardness measurements by Brinell method and electrical conductivity measurements. EDS results were compared with predicted phase equilibria and good overall agreement between experimental and calculated values was obtained. XRD results were also in agreement with predicted phase equilibria. Hardness and electrical conductivity of selected alloys were measured and by using appropriated mathematical model these properties were predicted in the whole composition range

Mechanical and electrical properties of the Bi-Ge-Sn alloys

© 2020, Association of Metallurgical Engineers of Serbia. All rights reserved. Mechanical and electrical properties of the ternary Bi-Ge-Sn alloys were investigated in this study. Calculation of isothermal section at 200, 300, and 25 ºC was carried out by using optimized thermodynamic parameters for the constitutive binary systems. Microstructures of alloys were observed by using optical microscopy and scanning electron microscopy (SEM). Phases in microstructures have been detected by X-ray diffraction (XRD) analysis and compositions of the phase by energy dispersive spectrometry (EDS). EDS results were compared with the predicted isothermal section at 200 and 300 ºC, and good agreement has been reached between them. The Brinell hardness and electrical conductivity of selected alloys were measured. Through ANOVA analysis and application of the obtained results, an appropriate mathematical model is proposed for every composition of alloys. By using the appropriated mathematical model for Brinell hardness and electrical conductivity, isolines for those properties were presented

Structural, mechanical and electrical properties of selected alloys in ternary Ag-Bi-Zn system are presented in this paper

© 2015 CSIC. Chosen alloys were investigated using X-Ray Diffraction (XRD), light optical microscopy, Scanning Electron Microscopy combined with Energy Dispersive Spectrometry (SEM-EDS), as well as by electrical conductivity and Brinell hardness measurements. Isolines of electrical conductivity and hardness for the entire Ag-Bi-Zn system were calculated using regression models.

Electrical properties of ternary Bi-Ge-Sb and Al-Cu-Sb alloys

Copyright: © 2017 CSIC. Electrical properties of ternary Bi-Ge-Sb and Al-Cu-Sb alloys. This paper presents review of electrical properties of two ternary systems based on Sb, ternary Bi-Ge-Sb and Al-Cu-Sb system. Beside electrical properties in paper are presented microstructures of both systems observed with light optical microscopy. On four samples microstructural analysis was carried out by scanning electron microscopy combined with energy dispersive spectrometry and X-ray powder diffraction technique. Moreover, micro hardness of selected alloys from the ternary Bi-Ge-Sb system was determined using Vickers hardness tests