X-ray studies on phase equilibria in {Tm, Lu} - W - B ternary systems at 1070 K

The phase equilibrium relationships of several vanadate systems have been studied by a combination of differential thermal analysis (DTA) and X-ray powder diffraction methods. All systems studied were eutectic in nature. The liquidus temperatures of the sodium vanadates were found to depend on the oxygen partial pressure for sodium oxide concentrations between 1.0 and 36 mol%. This effect was not observed for the ferric vanadate, chromic vanadate or magnesium vanadate systems. The solid–liquid phase equilibria for the ternary vanadate systems V2O5–Na2O–Fe2O3, V2O5–Na2O–Cr2O3, and V2O5–Na2O–MgO were measured by determining the temperature–composition data for various quasi-binary systems within each ternary system. Liquidus temperatures between 500 and 700 °C were found for those compositional ranges containing greater than 40 mol% V2O5 and between 10 and 60 mol% Na2O. The liquidus temperatures decreased with increasing oxygen partial pressure over much of the same compositional range.

Download Full-text

Phase equilibria and structural chemistry in the ternary systems M–Si–N and M–B–N (M = Al, Cu, Zn, Ag, Cd, In, Sn, Sb, Au, Tl, Pb, Bi)

Journal of Materials Research ◽

10.1557/jmr.1990.2152 ◽

1990 ◽

Vol 5 (10) ◽

pp. 2152-2159 ◽

Cited By ~ 23

Author(s):

F. Weitzer ◽

K. Remschnig ◽

J. C. Schuster ◽

P. Rogl

Keyword(s):

Melting Point ◽

Phase Equilibria ◽

Ternary Systems ◽

Compound Formation ◽

Isothermal Sections ◽

X Ray ◽

Cell Dimensions ◽

Powder Analysis ◽

Binary Compounds ◽

Unit Cell Dimensions

Phase equilibria in the ternary systems M–Si–N and M–B–N (M = Cu, Ag, Au, Zn, Cd, Al, In, Tl, Sn, Pb, Sb, and Bi) at temperatures 50–100 °C below the melting point of the metal components were investigated by means of x-ray powder analysis and are represented in the form of isothermal sections. No ternary compound formation was observed in any of the combinations M–Si–N and M–B–N. Silicon nitride and boron nitride, respectively, coexist with all metals investigated and with all binary compounds stable at the chosen temperatures. From unit cell dimensions negligible mutual solid solubilities are indicated between Si3N4 or BN and the metal components.

Download Full-text

Phase equilibria in the ternary Ag-Au-Ga system: Isothermal sections at 250°C and 450°C

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb170531043j ◽

2017 ◽

Vol 53 (3) ◽

pp. 215-222 ◽

Cited By ~ 1

Author(s):

D. Jendrzejczyk-Handzlik

Keyword(s):

Phase Equilibria ◽

Ternary Systems ◽

X Ray Diffraction ◽

Isothermal Sections ◽

X Ray ◽

Ternary Compounds ◽

Literature Overview ◽

Eds Analysis ◽

Two Temperatures ◽

Scanning Electron

The ternary Ag-Au-Ga system seems to be interesting in jeweller?s craft as a joint. Moreover, the ternary systems based on gold and silver have found applications in the dental industry. A literature overview of the Ag-Au-Ga system shows that the information about phase equilibria of this system does not exist. In the present work, phase equilibria in the Ag-Au-Ga ternary system have been studied by using scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) analysis and X-ray diffraction analysis (XRD). Twenty two annealed alloys in the 10-70 at.% Ga region have been investigated. Obtained experimental results were compared with the predicted isothermal sections at two temperatures (250?C and 450?C). No ternary compounds are found.

Download Full-text

Solid State Phase Equilibria in the Er-Ni-P and Er-Ni-As Systems at 800 °C

Zeitschrift für Naturforschung B ◽

10.1515/znb-2007-0907 ◽

2007 ◽

Vol 62 (9) ◽

pp. 1143-1152 ◽

Cited By ~ 6

Author(s):

Mariya Zelinska ◽

Olga Zhak ◽

Stepan Oryshchyn ◽

Tetiana Polianska ◽

Jean-Yves Pivan

Keyword(s):

Solid State ◽

Phase Equilibria ◽

Single Crystal ◽

Electron Probe ◽

Ternary Systems ◽

Structure Type ◽

Hexagonal Structure ◽

X Ray Diffraction ◽

X Ray ◽

System A

Solid-state phase equilibria in the ternary systems Er-Ni-P and Er-Ni-As have been determined at 800 °C (region 0 - 67 at.% P or 0 - 50 at.% As) using X-ray diffraction, scanning electron microscopy and electron probe microanalysis. Eight ternary phosphides and six ternary arsenides have been synthesized, including several phases reported previously. The hexagonal structure of the new compound Er6Ni20P13, as determined from single-crystal X-ray data, exhibits a new structure type closely related to the Ho6Ni20P13 structure. Two other new phosphides, Er16Ni36P22 (Tb16Ni36P22- type) and Er20Ni42P30 (Sm20Ni41.6P30-type), have also been obtained at 800 °C. In the Er-Ni-As system, a new arsenide Er20Ni42As30 (Sm20Ni41.6P30-type) has been found in addition to known ternary phases. From X-ray powder data, the structures of the ternary arsenides ErNi4As2 (ZrFe4Si2-type) and Er2Ni12As7 (Zr2Fe12P7-type) have been refined by Rietveld methods. In the single crystal investigations, two other new phases Er12Ni30P21 [derived (La, Ce)12Rh30P21-type] and Er13Ni25As19 (Tm13Ni25As19-type) have been prepared by high-temperature annealing (1500 °C).

Download Full-text

X-RAY STUDY OF CUBIC PHASES IN TERNARY SYSTEMS OF SURFACTANT DDAB, WATER AND OIL

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1990703 ◽

1990 ◽

Vol 51 (C7) ◽

pp. C7-25-C7-34 ◽

Cited By ~ 3

Author(s):

P. BAROIS ◽

D. EIDAM ◽

S. T. HYDE

Keyword(s):

Ternary Systems ◽

X Ray ◽

Cubic Phases

Download Full-text

Stable and Metastable Phase Equilibria Involving the Cu6Sn5 Intermetallic

Journal of Electronic Materials ◽

10.1007/s11664-021-09067-4 ◽

2021 ◽

Author(s):

A. Leineweber ◽

M. Löffler ◽

S. Martin

Keyword(s):

Phase Equilibria ◽

Electron Backscatter Diffraction ◽

Metastable Phase ◽

Stable Phase ◽

X Ray Diffraction ◽

X Ray ◽

Heat Treated ◽

Ordered Phases ◽

Backscatter Diffraction ◽

Kinetics Of

Abstract Cu6Sn5 intermetallic occurs in the form of differently ordered phases η, η′ and η′′. In solder joints, this intermetallic can undergo changes in composition and the state of order without or while interacting with excess Cu and excess Sn in the system, potentially giving rise to detrimental changes in the mechanical properties of the solder. In order to study such processes in fundamental detail and to get more detailed information about the metastable and stable phase equilibria, model alloys consisting of Cu3Sn + Cu6Sn5 as well as Cu6Sn5 + Sn-rich melt were heat treated. Powder x-ray diffraction and scanning electron microscopy supplemented by electron backscatter diffraction were used to investigate the structural and microstructural changes. It was shown that Sn-poor η can increase its Sn content by Cu3Sn precipitation at grain boundaries or by uptake of Sn from the Sn-rich melt. From the kinetics of the former process at 513 K and the grain size of the η phase, we obtained an interdiffusion coefficient in η of (3 ± 1) × 10−16 m2 s−1. Comparison of this value with literature data implies that this value reflects pure volume (inter)diffusion, while Cu6Sn5 growth at low temperature is typically strongly influenced by grain-boundary diffusion. These investigations also confirm that η′′ forming below a composition-dependent transus temperature gradually enriches in Sn content, confirming that Sn-poor η′′ is metastable against decomposition into Cu3Sn and more Sn-rich η or (at lower temperatures) η′. Graphic Abstract

Download Full-text

Photoconductivity of the Single Crystals Pb4Ga4GeS12 and Pb4Ga4GeSe12

Proceedings ◽

10.3390/proceedings2020062004 ◽

2020 ◽

Vol 62 (1) ◽

pp. 4

Author(s):

Hadj Bellagra ◽

Oksana Nyhmatullina ◽

Yuri Kogut ◽

Halyna Myronchuk ◽

Lyudmyla Piskach

Keyword(s):

Ternary Systems ◽

Semiconductor Materials ◽

Tetragonal Symmetry ◽

Bandgap Energy ◽

Experimental Measurements ◽

X Ray Diffraction ◽

X Ray ◽

Vertical Bridgman ◽

Symmetry Space ◽

Symmetry Space Group

Quaternary semiconductor materials of the Pb4Ga4GeS(Se)12 composition have attracted the attention of researchers due to their possible use as active elements of optoelectronics and nonlinear optics. The Pb4Ga4GeS(Se)12 phases belong to the solid solution ranges of the Pb3Ga2GeS(Se)8 compounds which form in the quasi-ternary systems PbS(Se)−Ga2S(Se)3−GeS(Se)2 at the cross of the PbGa2S(Se)4−Pb2GeS(Se)4 and PbS(Se)−PbGa2GeS(Se)6 sections. The quaternary sulfide melts congruently at 943 K. The crystallization of the Pb4Ga4GeSe12 phase is associated with the ternary peritectic process Lp + PbSe ↔ PbGa2S4 + Pb3Ga2GeSe8 at 868 K. For the single crystal studies, Pb4Ga4GeS(Se)12 were pre-synthesized by co-melting high-purity elements. The X-ray diffraction results confirm that these compounds possess non-centrosymmetric crystal structure (tetragonal symmetry, space group P–421c). The crystals were grown by the vertical Bridgman method in a two-zone furnace. The starting composition was stoichiometric for Pb4Ga4GeS12, and the solution-melt method was used for the selenide Pb4Ga4GeSe12. The obtained value of the bandgap energy for the Pb4Ga4GeS12 and Pb4Ga4GeSe12 crystals is 1.86 and 2.28 eV, respectively. Experimental measurements of the spectral distribution of photoconductivity for the Pb4Ga4GeS12 and Pb4Ga4GeSe12 crystals exhibit the presence of two spectral maxima. The first lies in the region of 570 (2.17 eV) and 680 nm (1.82 eV), respectively, and matches the optical bandgap estimates well. The locations of the admixture maxima at about 1030 (1.20 eV) and 1340 nm (0.92 eV), respectively, agree satisfactorily with the calculated energy positions of the defects vs. and VSe.

Download Full-text