The Si–Sr and Si–Ba phase diagrams over the Si-rich composition range

Abstract DTA and powder x-ray diffraction measurements allowed to draw the phase diagrams of the systems AgI-Ag2XO4 (X = Cr, Mo, W). A more detailed investigation was devoted to the composition range around XAgI = 0.8, where in preliminary tests it was observed that the room temperature ionic conductivity strongly depends on the thermal treatment of the sample. By quenching mixtures at XAgI = 0.8, glass-like phases with high conductivity were obtained; in the systems AgI-Ag2CrO4 and AgI-Ag2MO4 the subsequent crystallization gave rise to non con-ducting phases, whereas the occurrence of the highly conducting compound 4AgI·Ag2WO4 was recognized in the third system investigated.

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Thermodynamic assessment of the Sb–S and In–S binary systems

International Journal of Materials Research (formerly Zeitschrift fuer Metallkunde) ◽

10.1515/ijmr-2020-7951 ◽

2021 ◽

Vol 112 (5) ◽

pp. 373-383

Author(s):

Chuang Shi ◽

Na Li ◽

Weibin Zhang

Keyword(s):

Phase Diagrams ◽

Binary Systems ◽

Thermodynamic Assessment ◽

Composition Range ◽

Liquid Immiscibility ◽

Experiment Data ◽

Wide Composition Range ◽

Melting Compound ◽

Self Consistent ◽

Associate Species

Abstract The Sb–S and In–S binary systems were assessed thermodynamically using the CALculation of PHase Diagrams (CAL-PHAD) approach based on the experiment data in the literature. Both phase diagrams revealed a congruent melting compound and liquid immiscibility. Therefore, associate species, Sb2S3 and In2S3, were introduced into the associate model to describe the liquid phase during optimization. The binary intermediate compounds, Sb2S3, InS(α, β), and In6S7, were treated as stoichiometric phases. Considering the wide composition range, In2S3(α, β, γ), were modeled using the sublattice model. A set of self-consistent thermodynamic parameters representing most of the reliable thermodynamic properties and phase diagram information were derived.

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Calculation of activities in Ga-Cd and Cu-Pb binary systems

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb0204273m ◽

2002 ◽

Vol 38 (3-4) ◽

pp. 273-284 ◽

Cited By ~ 1

Author(s):

Dragan Manasijevic ◽

Dragana Zivkovic ◽

Zivan Zivkovic

Keyword(s):

Melting Point ◽

Phase Diagrams ◽

Binary Systems ◽

Composition Range ◽

Entire Composition Range ◽

Melting Point Depression ◽

Calculation Methods ◽

Duhem Equation ◽

Coexisting Phases ◽

Mutual Comparison

Calculations of activities in Ga-Cd and Cu-Pb binary systems were done based on their known phase diagrams, using different calculation methods. First, activities of cadmium at 700 K and copper at 1263 K in Ca - Cd and Cu - Pb systems, respectively, were calculated by melting point depression method and Zhang-Chou method for binary systems with phase diagrams involving two liquid or solid coexisting phases. In order to obtain activity values in the entire composition range, these methods were applied in the definite parts of composition range in both investigating systems. The same procedure was done, using modified Rao- Belton method by Chou, who used Richardson assumption. Activities of the second component in both investigating systems were calculated by use of Gibbs-Duhem equation. All calculated results were compared with literature data and mutual comparison between applied methods was done.

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Transmission electron microscope studies in special ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108489 ◽

1978 ◽

Vol 36 (1) ◽

pp. 268-269

Author(s):

A. Zangvil ◽

L.J. Gauckler ◽

G. Schneider ◽

M. Rühle

Keyword(s):

Phase Diagrams ◽

Crystal Structures ◽

Thin Foil ◽

Limited Extent ◽

Complex Materials ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Electron Microscopes ◽

Lattice Resolution

The use of high temperature special ceramics which are usually complex materials based on oxides, nitrides, carbides and borides of silicon and aluminum, is critically dependent on their thermomechanical and other physical properties. The investigations of the phase diagrams, crystal structures and microstructural features are essential for better understanding of the macro-properties. Phase diagrams and crystal structures have been studied mainly by X-ray diffraction (XRD). Transmission electron microscopy (TEM) has contributed to this field to a very limited extent; it has been used more extensively in the study of microstructure, phase transformations and lattice defects. Often only TEM can give solutions to numerous problems in the above fields, since the various phases exist in extremely fine grains and subgrain structures; single crystals of appreciable size are often not available. Examples with some of our experimental results from two multicomponent systems are presented here. The standard ion thinning technique was used for the preparation of thin foil samples, which were then investigated with JEOL 200A and Siemens ELMISKOP 102 (for the lattice resolution work) electron microscopes.

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