Diffusion-controlled solidification of a ternary melt from a cooled boundary

We present details of an experimental study of crystallization adjacent to a cooled boundary from an aqueous solution of potassium nitrate and sodium nitrate. This transparent system is typical of many ternary melts that do not form solid solutions, including examples in igneous petrology and metallurgy. We have measured the rates of advance of the front of crystallization and the eutectic front, behind which the system is completely solid. From careful measurements of the concentration and temperature fields, we have been able to infer the location of an internal phase boundary: the cotectic front separating a region in which only one component of the ternary system forms crystals from a region in which two components form crystals. Our experiments were conducted under conditions in which fluid flow is minimal, so that rates of crystallization are determined principally by the diffusive transport of heat. We have confirmed that the thicknesses of the various regions all grow in proportion to the square root of time, as is expected of diffusion-limited growth, and have determined the constants of proportionality for a range of different initial concentrations and boundary temperatures. We have found evidence to suggest that there may be a significant nucleation delay in the secondary and tertiary crystallization. Our measurements of concentration provide much more information about the ternary phase diagram than has hitherto been available.

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Diffusion limited growth-up of channels of ICF and its influence on integral flow through the channel

Magnetohydrodynamics ◽

10.22364/mhd.45.4.16 ◽

2009 ◽

Vol 45 (4) ◽

pp. 613-621

Author(s):

V. Frishfelds ◽

◽

A. Jakovičs ◽

B. Nacke ◽

E. Baake ◽

...

Keyword(s):

Limited Growth ◽

Diffusion Limited ◽

Flow Through

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Using phase boundary mapping to resolve discrepancies in the Mg2Si–Mg2Sn miscibility gap

Journal of Materials Chemistry A ◽

10.1039/d1ta00115a ◽

2021 ◽

Author(s):

Rachel Orenstein ◽

James P. Male ◽

Michael Toriyama ◽

Shashwat Anand ◽

G. Jeffrey Snyder

Keyword(s):

Phase Diagram ◽

Phase Boundary ◽

Ternary Phase ◽

Ternary Phase Diagram ◽

Miscibility Gap ◽

Boundary Mapping

A new understanding of the MgSi–MgSn miscibility gap is reached through phase boundary mapping the Mg–Si–Sn ternary phase diagram.

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Lattice evolution, ordering transformation and microwave dielectric properties of rock-salt Li3+xMg2–2xNb1-xTi2xO6 solid-solution system: A newly developed pseudo ternary phase diagram

Acta Materialia ◽

10.1016/j.actamat.2021.116636 ◽

2021 ◽

Vol 206 ◽

pp. 116636

Author(s):

Xing Zhang ◽

Zixuan Fang ◽

Hongyu Yang ◽

Peng Zhao ◽

Xiao Zhang ◽

...

Keyword(s):

Phase Diagram ◽

Solid Solution ◽

Dielectric Properties ◽

Ternary Phase ◽

Ternary Phase Diagram ◽

Microwave Dielectric Properties ◽

Solution System ◽

System A ◽

Microwave Dielectric ◽

Solid Solution System

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Calculation of phase diagrams and thermodynamic properties of 14 additive and reciprocal ternary systems containing Li2CO3, Na2CO3, K2CO3, Li2SO4, Na2SO4, K2SO4, LiOH, NaOH, and KOH

Canadian Journal of Chemistry ◽

10.1139/v84-078 ◽

1984 ◽

Vol 62 (3) ◽

pp. 457-474 ◽

Cited By ~ 19

Author(s):

A. D. Pelton ◽

C. W. Bale ◽

P. L. Lin

Keyword(s):

Phase Diagram ◽

Thermodynamic Properties ◽

Molten Salt ◽

Phase Diagrams ◽

Binary Systems ◽

Ternary Phase ◽

Ternary Phase Diagram ◽

Ternary Systems ◽

Maximum Error ◽

Critical Assessment

Phase diagrams and thermodynamic properties of five additive molten salt ternary systems and nine reciprocal molten salt ternary systems containing the ions Li+, Na+, [Formula: see text], OH− are calculated from the thermodynamic properties of their binary subsystems which were obtained previously by a critical assessment of the thermodynamic data and the phase diagrams in these binary systems. Thermodynamic properties of ternary liquid phases are estimated from the binary properties by means of the Conformal Ionic Solution Theory. The ternary phase diagrams are then calculated from these thermodynamic properties by means of computer programs designed for the purpose. It is found that a ternary phase diagram can generally be calculated in this way with a maximum error about twice that of the maximum error in the binary phase diagrams upon which the calculations are based. If, in addition, some reliable ternary phase diagram measurements are available, these can be used to obtain small ternary correction terms. In this way, ternary phase diagram measurements can be smoothed and the isotherms drawn in a thermodynamically correct way. The thermodynamic approach permits experimental data to be critically assessed in the light of thermodynamic principles and accepted solution models. A critical assessment of error limits on all the calculated ternary diagrams is made, and suggestions as to which composition regions merit further experimental study are given.

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The Formation of Cu3Si from Cu/a-Si Multilayers

MRS Proceedings ◽

10.1557/proc-481-581 ◽

1997 ◽

Vol 481 ◽

Cited By ~ 1

Author(s):

R. R. Chromik ◽

W. K. Neils ◽

E. J. Cotts

Keyword(s):

Diffusion Couples ◽

X Ray Diffraction ◽

Limited Growth ◽

Scanning Calorimetry ◽

Individual Layer ◽

Diffusion Limited ◽

Reaction Constant ◽

Multilayered Composites ◽

Reaction Constants ◽

Kinetics Of

ABSTRACTThe kinetics of the formation of Cu3Si in Cu/a-Si diffusion couples have been investigated by means of differential scanning calorimetry and x-ray diffraction. Multilayered composites of average stoichiometry Cu3Si were prepared by sputter deposition with individual layer thicknesses varying in different samples between 2 and 100 nm. We observed diffusion limited growth of Cu3 Si upon annealing these diffusion couples below 500 K. Reaction constants were measured for a temperature range of 455 to 495 K for thicknesses of growing Cu3Si between 2.6 and 80 nm. The temperature dependence of the reaction constant, k2, was characterized as k2 = k0 exp(− Ea/kbT) with activation energy, Ea = 1.0 eV/atom and pre-factor, k0 = 1.9×10−3 cm2/s.

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Part II. Model for the Protective Coating Formation During Hot Dip Galvanizing/ Część II. Model Formowania Powłoki Ochronnej Podczas Cynkowania Ogniowego

Archives of Metallurgy and Materials ◽

10.2478/amm-2014-0237 ◽

2014 ◽

Vol 59 (4) ◽

pp. 1393-1404 ◽

Cited By ~ 3

Author(s):

W. Wołczynski ◽

Z. Pogoda ◽

G. Garzeł ◽

B. Kucharska ◽

A. Sypien ◽

...

Keyword(s):

Phase Diagram ◽

Mass Balance ◽

Protective Coating ◽

Mathematical Description ◽

Ternary Phase ◽

Ternary Phase Diagram ◽

Solute Redistribution ◽

Zinc Bath ◽

Flux System ◽

Coating Formation

Abstract A mathematical description for the (Zn) - coating formation with the presence of flux in the zinc bath is presented. This description includes the progressive vanishing of the products of the flux disintegration. A function which expresses the flux vanishing is formulated. The solidification of some phase sub-layers in the (Zn) - coating is considered with the use of a hypothetical pseudo-ternary phase diagram Fe-Zn-flux. Some relationships are formulated to define the varying Zn - solute redistribution as observed across the sub-layers. The relationships are based on the mass balance analyzed for the coating / bath / flux system. An amount of the growing phase in a given sub-layers is also defined mathematically.

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