Phase Equilibria and Primary Crystallization Field for Sm1+yBa2-yCu3O7 at Various p(O2).

ChemInform ◽  
2005 ◽  
Vol 36 (1) ◽  
Author(s):  
C. Wende ◽  
B. Schuepp ◽  
G. Krabbes
Keyword(s):  
Phase Equilibria ◽  
Primary Crystallization ◽  
Crystallization Field ◽  
Primary Crystallization Field

Effect of Ag on the primary phase field of the high-Tc (Bi,Pb)-2223 superconductor

2000 ◽  
Vol 15 (2) ◽  
pp. 296-305 ◽  
Author(s):  
W. Wong-Ng ◽  
L. P. Cook ◽  
W. Greenwood ◽  
A. Kearsley
Keyword(s):  
Phase Field ◽  
Volume Fraction ◽  
Primary Crystallization ◽  
Primary Phase ◽  
Crystallization Field ◽  
Primary Phase Field ◽  
Liquidus Data ◽  
Primary Crystallization Field ◽  
High Tc ◽  
Melt Composition

The subsolidus equilibria and the primary phase field (crystallization field) of the 110 K high-Tc (Bi,Pb)-2223 ([Bi,Pb]:Sr:Ca:Cu) phase have been determined in the presence of Ag under a 92.5% Ar/7.5% O2 atmosphere (volume fraction). A total of 29 six-phase volumes that include both the (Bi,Pb)-2223 and Ag phases was observed. These subsolidus volumes are similar to those observed without the presence of Ag. The compositional range of initial melts of these volumes (mole fraction basis) covers BiO1.5 from 5.6% to 25.3%, PbO from 0.4% to 13.8%, SrO from 8.4% to 31.9%, CaO from 12.2% to 33.3%, CuO from 21.7% to 40.9%, and AgO0.5 from 1.2% to 6.3%. Based on these data, the primary crystallization field for the (Bi,Pb)-2223 phase in the presence of Ag was constructed using the convex hull technique. A section through this “volume” was portrayed by holding the AgO0.5, SrO, and CaO components at the median value of the 29 compositions while allowing projection on the other three axes (BiO1.5, PbO, and CuO). The net effect of Ag on the melt composition is a reduction in the PbO concentration and an increase in the SrO content. Applications of the liquidus data are also discussed.

The primary crystallization field and growth of Bi-2212 crystals in platinum and gold crucibles

2001 ◽  
Vol 231 (1-2) ◽  
pp. 194-202 ◽  
Author(s):  
A.B. Kulakov ◽  
I.G. Naumenko ◽  
S.A. Zver’kov ◽  
A.V. Kosenko ◽  
S.S. Khasanov ◽  
...  
Keyword(s):  
Primary Crystallization ◽  
Crystallization Field ◽  
Primary Crystallization Field

X-Ray Characterization of Phase Equilibria of the Raveau and 2212 Phases in the Bi-Sr-Ca-Cu-0 System

1995 ◽  
Vol 39 ◽  
pp. 731-738
Author(s):  
Winnie Wong-Ng ◽  
Lawrence P. Cook ◽  
F. Jiang
Keyword(s):  
Solid Solution ◽  
Phase Equilibria ◽  
Powder Diffraction ◽  
Primary Crystallization ◽  
Primary Crystallization Field ◽  
X Ray ◽  
Solid Solution Region ◽  
Ca Substitution ◽  
Solution Region

Phase equilibria of two superconductor phases, namely the 20K Raveau phase (Bi2.2-xSr1.8+xCuOz, currently referred to as the 11905 phase) and the 80K 2212 phase of the Bi-Sr-Ca-Cu-0 system were investigated. The amount of Ca-substitution of the Raveau solid solution was determined and the solid solution region can be approximately described as Bi2.2+xSr1.8-X-Y CayCu1±x/2Ow (referred to as the Ca-Raveau phase or the 119x5, ‘ with 0<x<0.15, 0<y<0.5. To determine the melting equilibria of the 2212 phase, a procedure involving the use of a wicking technique to capture the melt was applied. X-ray powder diffraction (XPD) and quantitative energy dispersive x-ray spectroscopy (EDS) were used to analyse the phases present in the residual and melt, respectively. The approximate primary crystallization field of the incongruently melting 2212 phase was illustrated.

scholarly journals Phase relations in the Tl2 Te–TlBiТe2 –TlTbTe2 system

2021 ◽  
Vol 23 (1) ◽  
pp. 32-40
Author(s):  
Samira Z. Imamaliyeva ◽  
Ganira I Alakbarzade ◽  
Dunya M. Babanly ◽  
Marina V. Bulanova ◽  
Vagif A. Gasymov ◽  
...  
Keyword(s):  
Phase Equilibria ◽  
Solid Solutions ◽  
Solid Phase ◽  
Liquidus Surface ◽  
Primary Crystallization ◽  
Wide Field ◽  
Isothermal Sections ◽  
X Ray ◽  
Δ Phase ◽  
Polythermal Sections

The phase equilibria in the Tl2Te–TlBiТe2–TlTbTe2 concentration area of the Tl–Bi–Tb-Te quaternary system were investigated by using the differential thermal analysis and powder X-ray diffraction techniques. The diagram of the solid-phase equilibria of this system at room temperature was constructed. It was established that the Tl9BiTe6–Tl9TbTe6 section divides the Tl2Te–TlBiТe2–TlTbTe2 system into two independent subsystems. It was found that the Tl2Te–Tl9BiTe6–Tl9TbTe6 subsystem is characterized by the formation of a wide field of solid solutions with a Tl5Te3 structure (δ-phase) that occupy more than 90% of the area of the concentration triangle. The results of X-ray phase analysis of alloys of the Tl9BiTe6–Tl9TbTe6–TlTbTe2–TlBiТe2 subsystem showed the formation of wide regions of solid solutions based on TlTbTe2 and TlBiTe2 along the section of TlTbTe2–TlBiTe2 ((β1- and β2-phases) and made it possible to determine the location of the heterogeneous phase regions in this subsystem. The parameters of crystal lattices of mutually saturated compositions of the β1-, β2-, and δ-phases are calculated from powder diffraction patterns.The paper also presents some polythermal sections, isothermal sections at 740 and 780 K of the phase diagram, as well as projections of the liquidus and solidus surfaces of the Tl2Te–Tl9BiТe6–Tl9TbTe6 subsystem. The liquidus surface consists of three fields of the primary crystallization of α (Tl2Te)-, δ- and β1-phase. The constructed isothermal sections clearly demonstrate that the directions of the tie lines do not coincide with the T–x planes of the studied internal sections, which is characteristic of non-quasi-binary polythermal sections. The obtained new phases are of interest as potential thermoelectric and magnetic materials.

Phase Equilibria at 1173K in the Ni-Ti-Al System

1982 ◽  
Vol 19 ◽  
Author(s):  
W.W. Liang ◽  
P. Nash
Keyword(s):  
Experimental Data ◽  
Phase Equilibria ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Composition Range ◽  
Primary Crystallization ◽  
X Ray Diffraction ◽  
Isothermal Sections ◽  
X Ray

ABSTRACTIn a recent review of the published literature on this system it was concluded that there is a lack of experimental data in this system particularly in regions of the system with less than 75 atomic per cent of each one of the components (1). In order to provide some consistent data over a substantial range of composition an experimental determination of the phase equilibria at 1173K and from 0–50 atomic % Al is being carried out. The main experimental technique being used is quantitative electron microprobe analysis (JEOL 733) by wavelength dispersive x-ray spectrometry. In addition, x-ray diffraction is being used to establish the structures of phases present and optical metallography of cast structures to determine the fields of primary crystallization. In addition to establishing the phase equilibria at this temperature the composition range for the existence of the AlNi2Ti phase is being determined. The results thus far are compared with previous experimental data and calculated isothermal sections (2).

Phase equilibria in the ternary reciprocal system Li, Ba // BO2, F and growth of bulk β-BaB2O4 crystals

2017 ◽  
Vol 50 (1) ◽  
pp. 22-29 ◽  
Author(s):  
E. A. Simonova ◽  
A. E. Kokh ◽  
N. G. Kononova ◽  
V. S. Shevchenko ◽  
D. A. Kokh ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Nonlinear Optical ◽  
Reciprocal System ◽  
Primary Crystallization ◽  
Primary Crystallization Field ◽  
Ternary Reciprocal System ◽  
X Ray ◽  
Visual Polythermal Analysis ◽  
Polythermal Sections ◽  
Phase Relationships

In order to find the optimum solvent for the growth of nonlinear optical β-BaB2O4 crystals, the phase relationships in the ternary reciprocal system Li, Ba // BO2, F have been studied using solid state synthesis, differential thermal analysis and X-ray powder diffraction. Isothermal and polythermal sections of the system Li, Ba // BO2, F are reported. In the studied system, the following compounds are formed: LiBa2B5O10 (melts by peritectic reaction at 930°C, i.e. 1203 K) and LiBaF3 (melts incongruently at 850°C, i.e. 1123 K). Visual polythermal analysis of seeding and growth of β-BaB2O4 crystals in this system was carried out. The primary crystallization field of β-BaB2O4 was defined. Using the top-seeded pulling technique, a β-BaB2O4 crystal of 93 mm in diameter, 34 mm in height and 520 g in weight has been grown.

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