Substitution Behavior of Ni3X-type Compounds with D0a Structure

2011 ◽  
Vol 1295 ◽  
Author(s):  
H. Sugimura ◽  
Y. Kaneno ◽  
T. Takasugi
Keyword(s):  
Thermodynamic Model ◽  
Ternary Phase ◽  
Single Phase ◽  
Heat Of Formation ◽  
Phase Region ◽  
Site Preference ◽  
Ternary Phase Diagrams ◽  
Host Compound ◽  
Ternary Additions ◽  
Good Agreement

ABSTRACTThe site preference of ternary additions in GCP (geometrically close-packed) Ni3X-type compounds with D0a structure was determined from the direction of the single-phase region of the D0a phase in the reported ternary phase diagrams. The thermodynamic model based on the Bragg-Williams approximation, which is based on the change in heat of formation of the host compound by a small addition of ternary solute, was applied to predict the site preference of ternary additions. The heat of formation used in the thermodynamic calculation was derived from Miedema’s formula. Good agreement was obtained between the thermodynamic model and the result of the literature search.

Alloying Behavior of Ni3Nb, Ni3V and Ni3Ti Compounds

2010 ◽  
Vol 654-656 ◽  
pp. 440-443 ◽  
Author(s):  
Hotaruko Sugimura ◽  
Yasuyuki Kaneno ◽  
Takayuki Takasugi
Keyword(s):  
Thermodynamic Model ◽  
Ternary Phase ◽  
Nearest Neighbor ◽  
Site Preference ◽  
Compound Formation ◽  
Ternary Phase Diagrams ◽  
Neighbor Pair ◽  
Relative Value ◽  
Host Compound ◽  
Ternary Additions

The site preference of ternary additions in Ni3X-type GCP compounds was determined from the direction of solubility lobe of the GCP phase on the experimentally reported ternary phase diagrams. In Ni3Nb (D0a), Co and Cu preferred the substitution for Ni-site, Ti, V and W the substitution for Nb-site, and Fe the substitution for both sites. In Ni3V (D022), Co preferred the substitution for Ni-site, Cr the substitution for both sites, and Ti the substitution for V-site. In Ni3Ti (D024), Fe, Co, Cu, and Si preferred the substitution for Ni-site, Nb, Mo and V the substitution for Ti-site. The thermodynamic model, which was based on the change in total bonding energy of the host compound by a small addition of ternary solute, was applied to predict the site preference of ternary additions. The bond energy of each nearest neighbor pair used in the thermodynamic calculation was derived from the heat of compound formation by Miedema’s formula. The agreement between the thermodynamic model and the result of the literature search was excellent. Both transition and B-subgroup elements have two possibilities, i.e., the case of substitution for Ni-site or the case for X-site, depending on the relative value of two interaction energies.

Ternary mixtures of phosphonium ionic liquids + organic solvents + water

2008 ◽  
Vol 80 (6) ◽  
pp. 1325-1335 ◽  
Author(s):  
Shahana A. Chowdhury ◽  
Janet L. Scott ◽  
Douglas R. MacFarlane
Keyword(s):  
Ionic Liquids ◽  
Organic Solvents ◽  
Ternary Phase ◽  
Single Phase ◽  
Ternary Mixtures ◽  
Green Solvents ◽  
Ternary Phase Diagrams ◽  
Tie Lines ◽  
Extraction Processes ◽  
Tie Line

Ionic liquids (ILs) and water are both potentially green solvents that are useful in a variety of extraction processes. This report presents the ternary phase diagrams and tie-line data of trihexyl(tetradecyl)phosphonium dicyanamide [P6,6,6,14][DCA], phosphonium bis(2,4,4-trimethylpentyl)phosphinate [P6,6,6,14][((CH3)3C5H8)2PO2], and 1-ethyl-3-methylimidazolium ethylsulfate [emim][C2H5SO4] ILs in organic solvents (ethanol, acetonitrile, toluene) and water. [P6,6,6,14][DCA] and [P6,6,6,14][((CH3)3C5H8)2PO2] tended to yield emulsions when combined with water and ethanol, while [emim][C2H5SO4] combined with toluene and water provided two clear phases of reasonable viscosity. The compositions of the ternary mixtures were determined to obtain the tie-lines. A noticeable difference was observed for the tie-lines of the same IL (e.g., [P6,6,6,14][DCA]) with different organic solvents (ethanol and acetonitrile) and water mixtures. In all cases, the addition of ethanol eventually produced a single phase.

Site preference determination in intermetallic compounds by thermal conductivity measurement

2001 ◽  
Vol 16 (8) ◽  
pp. 2314-2320 ◽  
Author(s):  
Yoshihiro Terada ◽  
Kenji Ohkubo ◽  
Tetsuo Mohri ◽  
Tomoo Suzuki
Keyword(s):  
Thermal Conductivity ◽  
Phase Diagrams ◽  
Intermetallic Compounds ◽  
Present Method ◽  
Ternary Phase ◽  
Conductivity Measurement ◽  
Site Preference ◽  
Polycrystalline Specimen ◽  
Ternary Phase Diagrams

A method for the determination of site preference of substitutional elements in intermetallic compounds is proposed. It is demonstrated in Ni3Al–X alloys that the ridge direction in thermal conductivity contours in the ternary γ′ phase agrees with that of the solubility lobe of the γ′ phase in ternary phase diagrams. The ridge direction is a reliable indication of site preference of substitutional elements in intermetallic compounds. The present method is conveniently applied to a normal polycrystalline specimen with small size, and therefore, a versatile class of brittle compounds can be studied.

scholarly journals Phase Manifestation and Formation of Nanoemulsions Composed of Imidazolium-based Ionic Liquid, Tween 80/Span 80 and Labrafac Lipophile WL 1349

2017 ◽  
Vol 32 (2) ◽  
pp. 85
Author(s):  
S. H. Ng ◽  
P. M. WOI ◽  
C. C. ENG
Keyword(s):  
Ionic Liquid ◽  
Phase Diagrams ◽  
Ternary Phase ◽  
Single Phase ◽  
Tween 80 ◽  
Continuous Phase ◽  
Good Stability ◽  
Sorbitan Monooleate ◽  
Ternary Phase Diagrams ◽  
Span 80

onic liquids (ILs) can enhance topical and transdermal delivery, as well as increase the solubility of sparingly soluble drugs. In the present work, pseudo-ternary phase diagrams of emulsions were composed of a mixture of non-ionic surfactants, polyoxyethylene sorbitan monooleate (Tween 80®) and sorbitan monooleate (Span 80®) in weight fraction: 1:1, 1:2, 2:1 and 2:3, LabrafacTM Lipophile WL 1349 as an oil phase and 1-hexyl-3-methylimidazolium chloride [(HMIM) (Cl)] as a continuous phase. Emulsion formulations were selected with 10% surfactants from the pseudo-ternary phase diagrams and further prepared at 298.2 ± 0.1 K. Acoustic emulsificationmethod was used to prepare nanoemulsions that were mixed with freshly prepared hydrocolloid gum. The area of the single-phase zone in pseudo-ternary phase diagrams that varied with Tween 80® /Span 80® ratio in the order of 2:1 > 1:1 > 2:3 > 1:2 where Span 80® was replaced by an equivalent weight of Tween 80®  to form IL-based nanoemulsions. [HMIM] [Cl] tended to create a two-phase system. Addition of carbopol® ultrez 20 copolymer into the continuous phase of the formulations gave single-phase nanoemulsions with good stability. The mixture of surfactants with weight ratio of 1:2 (Tween 80®/Span 80®) showed a good stability with the smallest particle size and greater surface charges in the system. These ionic liquid-based nanoemulsions might have the potential in drug delivery systems.

Crystalline and Liquid Phases in the Systems MeX2/Aniline/Water (Me-Ni,Co;X=NO,ClO4)

1989 ◽  
Vol 44 (2) ◽  
pp. 139-150
Author(s):  
Michacl Mahr ◽  
Helmut Paulus ◽  
Konrad G. Weil
Keyword(s):  
Ternary Phase ◽  
Single Phase ◽  
Ion Pairs ◽  
Cobalt Nitrate ◽  
Nickel Nitrate ◽  
X Ray Diffraction ◽  
Nickel Ions ◽  
Ternary Phase Diagrams ◽  
Liquid Phases ◽  
Nickel Perchlorate

Abstract Nickel nitrate, nickel Perchlorate and cobalt nitrate can form homogeneous liquid phases with aniline and water. The shapes of the single phase regions in the ternary phase diagrams were determined. Five types of crystals were obtained in the system nickel nitrate/aniline/water. The structures of Ni(NO3)2 · 6C6H7N · 2H2O, Ni(NO3)2 ·4C6H7N · 2H2O , and Ni(NO3)2 ·2C6H7N · 4H2O have been determined by single crystal X-ray diffraction. All structures show chains of nickel ions and nitrate ions connected by water or aniline molecules. They can be interpreted as one dimensional ion pairs.

On Some Ternary Phases in the Systems Nb-Zn-Al and Ta-Zn-Al

1982 ◽  
Vol 37 (10) ◽  
pp. 1225-1229 ◽  
Author(s):  
A. Drašner ◽  
Ž. Blažina
Keyword(s):  
Valence Electron ◽  
Ternary Phase ◽  
Single Phase ◽  
Phase Region ◽  
Valence Electron Concentration ◽  
Unit Cell Parameters ◽  
Laves Phases ◽  
X Ray ◽  
Cell Parameters ◽  
The Stability

Abstract In the systems NbZn2-xALx and TaZn2-xAlx a great number of samples was prepared and investigated by means of X-ray powder diffraction. In both systems at the equiatomic composition two new ternary phases were found. Their crystal structures were determined and found to belong to the Friauf-Laves type (MgZn2 prototype, S. G. P 63/mmc). The unit cell parameters of NbZnAl are a = 506.4 ± 0.2 pm, c = 829.9 ± 0.8 pm, c/a = 1.639, and for TaZnAl a = 503.8 ± 0.2 pm, c = 827.9 ± 0.3 pm, c/a= 1.643. In the system NbZn2-x-Alx, at the composition NbZn1.25Al0.75, a ternary phase of the AuCu3 structure (a= 394.4 i 0.3 pm, S. G. Pm3m) was also observed, while in the system NbZn3-xAlx a single phase region, having the AuCu3 structure, was found to exist up to the composition NbZ2Al. The stability of these Friauf-Laves phases and those found previously in the systems ZrZn2-xAlx and HfZn2-xAlx is discussed in terms of atomic sizes and valence electron concentration.

Phase Stability, Point Defects and Site Preference of Feal and Nial with Ternary Additions

1994 ◽  
Vol 364 ◽  
Author(s):  
C.L. Fu ◽  
J. Zou
Keyword(s):  
Defect Structure ◽  
Vacancy Concentration ◽  
Heat Of Formation ◽  
Site Preference ◽  
Stability Point ◽  
Order Of Magnitude ◽  
Ternary Additions ◽  
Fe Sites ◽  
Experimental Values ◽  
Fe Addition

AbstractFirst-principles calculations have been used to investigate the defect properties and the site preference of FeAl and NiAl with ternary additions. It is found that a “triple-defect” structure model becomes invalid in describing the defect structure of FeAl (which is weakly ordered). The calculated mono-vacancy concentration on the Fe sites is lower than available experimental values by an order of magnitude, which may suggest the formation of defect complexes or the need of sufficiently long annealing time to anneal out quenched-in vacancies. For the site preference of ternary additions in FeAl, Cr and Ti are found to occupy Al sublattices, whereas Ni has a distinct preference for the Fe sites. The substitutional behavior of ternary elements in FeAl is consistent with the trend in the calculated heat-of-formation. For Fe addition in Al-rich NiAl, Fe atoms occupy Ni sublattices exclusively. The site preference of Fe addition in Ni-rich NiAl is dependent on alloy composition and temperature. At low temperatures, Fe atoms are found to preferentially occupy Al sublattices in Ni-rich alloys.

SITE PREFERENCE AND VIBRATIONAL PROPERTIES OF Ni3Al WITH TERNARY ADDITIONS Pd AND Ag

2002 ◽  
Vol 16 (19) ◽  
pp. 727-737 ◽  
Author(s):  
YAN-MEI KANG ◽  
NAN-XIAN CHEN ◽  
JIANG SHEN
Keyword(s):  
Vibrational Properties ◽  
Site Preference ◽  
Phonon Density ◽  
Lattice Vibrations ◽  
Pair Potentials ◽  
Site Preferences ◽  
Debye Temperatures ◽  
Ternary Additions ◽  
Ternary Intermetallic Compounds ◽  
Good Agreement

The site preferences of Ag and Pd in Ni 3 Al are evaluated based on interatomic pair potentials that are converted from ab initio cohesive energy and Möbius–Chen's lattice inversion theorem. The calculated results are in good agreement with experimental data. Thus, the phonon density of states for (Ni,Pd) 3 Al and Ni 3 (Al,Ag) , the corresponding Einstein and Debye temperatures are also evaluated, which describe phenomena associated with lattice vibrations of ternary intermetallic compounds.

scholarly journals Experimental and thermodynamic description of ternary Bi-Cu-Ga system

2017 ◽  
Vol 53 (3) ◽  
pp. 189-201 ◽  
Author(s):  
D. Minic ◽  
Y. Du ◽  
M. Premovic ◽  
D. Manasijevic ◽  
N. Talijan ◽  
...  
Keyword(s):  
Phase Diagram ◽  
Ternary Phase ◽  
Energy Dispersive Spectrometry ◽  
Thermodynamic Description ◽  
Calculated Phase Diagram ◽  
Calphad Method ◽  
Experimental Result ◽  
Liquidus Phase ◽  
Ternary Phase Diagrams ◽  
Good Agreement

Phase diagram of the Bi-Cu-Ga ternary system has been investigated experimentally with 27 alloys and analytically by using a Calphad method. Thirteen annealed alloys at 200?C were investigated by using scanning electron microscopy (SEM) with energy dispersive spectrometry (EDS), and X-ray powder diffraction (XRD) methods. Temperatures of phase transformation were determined with 14 alloys which are lying along three vertical sections Bi-Cu0.5Ga0.5, Cu-Bi0.5Ga0.5 and Ga-Bi0.5Cu0.5 by using differential thermal analysis (DTA). Based on the experimental result and by using Calphad method, ternary phase diagrams were constructed with a new description of liquidus phase. Calculated phase diagram and experimentally obtained results are in good agreement. Liquidus projection and invariant reaction were calculated by using new thermodynamic parameters for liquidus phase.

Change of Ms Temperatures and its Correlation to Atomic Configurations of Offstoichiometric NiTi-Cr and NiTi-Co Alloys

1996 ◽  
Vol 459 ◽  
Author(s):  
Hideki Hosoda ◽  
Toshihiko Fukul ◽  
Kanryu Inoue ◽  
Yoshlnao Mishima ◽  
Tomoo Suzuki
Keyword(s):  
Electronic Structures ◽  
Single Phase ◽  
Phase Region ◽  
Two Phase ◽  
Niti Alloys ◽  
Constituent Element ◽  
Ternary Additions ◽  
Co Alloys ◽  
Rich Side ◽  
Degree Of Order

ABSTRACTEffects of compositional deviation from the stoichiometry and Cr and Co additions on martensitic-transformation-slart and auslenite-start temperatures (Ms and As) of offstoichiometric NiTi alloys are investigated. Ms and As are determined using conventional differential thermal analysis (DTA), where the temperature range investigated is between 77K and 423K. Alloys are widely chosen with both Ni- and Ti-rich compositions, to which ternary elements, Cr and Co, are added. It is clearly shown that Ms and As in single phase regions are reduced with increasing amount of constituent element, Ni, and ternary elements, Cr and Co. On the other hand, Ms and As do not depend on Ti concentration when Ti concentration is more than 52mol.%. NiTi alloys are in two phase region in the case. Ms changes by Co at offstoichiometry are evaluated to be -15K / mol.% in Ni poor side and -30K / mol.% in Ni rich side. These values correspond to -22K / mol.% for the stoichiometric NiTi alloys. Also, effects of Cr on Ms are evaluated to be -65K / mol.% in Ni poor side and -45K / mol.% in Ni rich side. The former is similar to the Ms change in stoichiometric alloys, and the latter is close to our prediction of -30K / mol.% in comparison with the reported value of -120K / mol.% for stoichiometric alloys. It is concluded for offstoichiometric NiTi alloys that effects of ternary additions on Ms can be explained using electronic structures of ternary elements by taking atomic configurations into account, as well as the stoichiometric NiTi alloys. Effect of degree of order is also discussed.

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