The wetting of some solid transition metals by liquid lithium, sodium, and potassium

1966 ◽  
Vol 19 (7) ◽  
pp. 1093
Author(s):  
DO Jordan ◽  
JE Lane
Keyword(s):  
Contact Angles ◽  
Solid Metal ◽  
Liquid Lithium ◽  
Temperature Range ◽  
The Stability ◽  
Solid Liquid Interface ◽  
Solid Liquid ◽  
Rigid Surfaces ◽  
Spontaneous Wetting ◽  
Sodium And Potassium

Spontaneous wetting of plane, rigid surfaces resulting solely from surface forces is shown to occur only in those systems in which advancing angles of zero are observed. Contact angles were measured for 12 solid metal-liquid metal systems consisting of a transition metal and an alkali metal. In the temperature range up to 250�, zero advancing angles were observed for the systems Cu-Li, Sa-Hg, Ag-Se, Au-Na, Pt-Ka, Pd-Na, Zn-Na, Ag-K, Zn-K. In the same temperature range, only non-zero advancing angles could be obtained for the systems Cu-Na, Ni-Na, and Cu-K. The reason for the non-wetting in the latter three systems is discussed in terms of two alternative models, one based on the degree of misfit at the solid-liquid interface, and the other on the stability of oxides on the solid metal surface. These alternative explanations probably have a common origin.

Effect of Heating Temperature on Microstructure of Directionally Solidified Ni-43Ti-7Al Alloy

2017 ◽  
Vol 898 ◽  
pp. 552-560 ◽  
Author(s):  
Lei Zhou ◽  
Li Jing Zheng ◽  
Hu Zhang
Keyword(s):  
Volume Fraction ◽  
Heating Temperature ◽  
Thermal Gradients ◽  
Directionally Solidified ◽  
Melt Structure ◽  
Cast Sample ◽  
The Stability ◽  
Solid Liquid Interface ◽  
Solid Liquid ◽  
Liquid Metal Cooling

By liquid metal cooling (LMC) process, the Ni-43Ti-7Al (at.%) alloy has been directionally solidified (DS) at different heating temperatures (1450°C, 1550°C, 1650°C) and a constant withdrawal rate of 100μm/s. The results showed that anomalous eutectic structures which consisted of Ti2Ni and TiNi phases were formed at the grain boundaries of as-cast sample and similar structures were also observed in the intercellular regions of DS samples. However, the microstructure changed from the equiaxial structure to the cellular structure due to the axial thermal gradients imposed. After DS, the NiTi and Ti2Ni phases preferentially grew along certain orientation, but the preferred crystallographic orientations of them changed as the heating temperature increased to 1650°C, which might be related to the change of melt structure. As expected, the volume fraction of Ti2Ni increased from 3.3% to 5.2% and the cellular spacing decreased from 47.8μm to 27.0μm as heating temperature increased. In addition, the stability of solid/liquid interface decreased, resulting from the coupling effects of G and ΔT- with the heating temperature increasing.

Stability of Thermoelectromagnetic Convection

2006 ◽  
Author(s):  
Brent C. Houchens
Keyword(s):  
Numerical Solutions ◽  
Liquid Interface ◽  
Analytical And Numerical Solutions ◽  
The Stability ◽  
Solid Liquid Interface ◽  
Solid Liquid ◽  
Initial Results

The role of thermoelectromagnetic convection (TEMC) on the stability of a range of flows is investigated. Here we discuss the general features of TEMC, and describe experiments in which this effect is thought to have significance. The general formulation for TEMC at a solid-liquid interface is presented. Initial results are benchmarked with existing analytical and numerical solutions.

Evolution of the Solidification Microstructure of Rheocast High Purity Aluminium

2012 ◽  
Vol 192-193 ◽  
pp. 109-115 ◽  
Author(s):  
Sarah George ◽  
Robert Knutsen
Keyword(s):  
High Purity ◽  
Liquid Interface ◽  
Cellular Growth ◽  
Solidification Mode ◽  
Purity Aluminium ◽  
High Purity Aluminium ◽  
Semi Solid ◽  
The Stability ◽  
Solid Liquid Interface ◽  
Solid Liquid

High purity aluminium has been successfully rheocast using the CSIR-RCS system combined with high pressure die casting. Analysis of the as-cast microstructure by SEM and EBSD revealed the presence of in-grain substructures. These morphological features show that the overall growth mode of the globular grains during rheocasting is planar, but the presence of these features indicates that the solidification mode is cellular at some stages during the slurry production process. Cellular solidification is associated with unstable growth at the solid-liquid interface and is initiated and exacerbated by solute gradients between the melt and the newly formed solid. This high purity alloy exhibits the same cellular growth, indicating that even minor solute variations have an effect on the stability of the solid-liquid interface and, hence, the mode of solidification during semi-solid rheocasting.

Faceting of Σ3 Grain Boundaries in Al

2007 ◽  
Vol 558-559 ◽  
pp. 949-954 ◽  
Author(s):  
Svetlana Protasova ◽  
Olga A. Kogtenkova ◽  
Boris B. Straumal
Keyword(s):  
Temperature Dependence ◽  
Interface Energy ◽  
Contact Angles ◽  
Al Alloy ◽  
Liquid Interfaces ◽  
Bridgman Technique ◽  
The Third ◽  
Crystallographic Facets ◽  
Solid Liquid Interface ◽  
Solid Liquid

The temperature dependence of the energy of various facets of twin GBs has been measured. For the investigation of GB faceting the Al bicrystals of 99.999% wt. purity were grown by the modified Bridgman technique. One grain in these bicrystals is semi-surrounded by another one. Bicrystals were coated with a layer of Sn–Al alloy and annealed at various temperatures. Contact angles at the junction of a GB and two solid/liquid interfaces have been measured. The ratios of GB energy to solid/liquid interface energy have been calculated. Using these data, the Wulff-Herring plots and GB phase diagrams were constructed. Three different crystallographic facets were observed for the coincidence GB. Two of them are stable at all studied temperatures, the third one becomes metastable below ~ 800K. In GBs with θ = 3° only one facet (symmetric twin GB) is stable.

Convective influence on the stability of a cylindrical solid–liquid interface

1985 ◽  
Vol 151 (-1) ◽  
pp. 121 ◽  
Author(s):  
Q. T. Fang ◽  
M. E. Glicksman ◽  
S. R. Coriell ◽  
G. B. McFadden ◽  
R. F. Boisvert
Keyword(s):  
Liquid Interface ◽  
Cylindrical Solid ◽  
The Stability ◽  
Solid Liquid Interface ◽  
Solid Liquid

scholarly journals Atomistic modeling of the propagation of the melting/crystallization front for metals based on the generalization of the modified transition state theory

2021 ◽  
pp. 1-20
Author(s):  
Vladimir Ivanovich Mazhukin ◽  
Alexander Viktorovich Shapranov ◽  
Olga Nikolaevna Koroleva ◽  
Alexander Vladimirovich Mazhukin
Keyword(s):  
Kinetic Model ◽  
State Theory ◽  
Atomistic Modeling ◽  
Dynamics Modeling ◽  
Temperature Range ◽  
Diffusion Limited ◽  
Molecular Dynamics Modeling ◽  
Solid Liquid Interface ◽  
Solid Liquid ◽  
Speed Response

Based on the modification of the well-known kinetic model with the Wilson-Frenkel diffusion constraint, a new kinetic model of the propagation velocity of the solid/liquid interface in various metal crystals (fcc - Al, Cu) and (bcc - Fe) has been developed in a wide temperature range, including the range of maximum permissible overheating/subcooling values. Molecular dynamics modeling of melting/crystallization processes of Al, Cu and Fe under deep overheating/overcooling conditions has been performed using 3 interaction potentials of the EAM family. By comparing the simulation results with the data of the modified kinetic model, the interface speed response function in the region of the maximum permissible values of overheating/overcooling in metals is constructed. The temperature dependence of the velocity of the interface is diffusion-limited and is described by the same equation for each metal in the entire temperature range.

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