Effect of Ag alloying and trace precipitation on corrosion resistance of Ti-Ta-Ag ternary alloy

This work systematically analysed the electrochemical and corrosion behaviour of Ti-Ta-Ag ternary alloy samples in Hank's solution. For the samples with 1.5% and 3% Ag content, the sintering temperature increased from 750 to 950°C, and the corresponding corrosion resistance increased by 100 times due to the increased alloying of Ag; meanwhile for the sample with 4.5% Ag content, the sintering temperature increased from 750 to 950°C, and the corresponding corrosion resistance decreased by six times due to the increased precipitation of Ag. These tests prove that the Ag alloying is beneficial to the enhancement of the corrosion resistance of Ti-Ta-Ag ternary alloy, but the Ag trace precipitation has the opposite effect. A series of electrochemical characterizations and density functional theory calculations explain the mechanism of the above phenomenon. Ag alloying can promote the formation of uniform, complete, dense, stable and thick passivation layer on the surface of Ti-Ta-Ag ternary alloy, which makes Ti-Ta-Ag ternary alloy uniformly corroded without pitting. In addition, Ag alloying can effectively reduce the contact resistance of the solid–liquid interface. However, the trace precipitation of Ag plays the opposite role to the above effect.

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Molecular orientation in fluids near solid-liquid interface as studied by the density functional method

Studies in Physical and Theoretical Chemistry - Structure, Fluctuation, and relaxtion in solutions, Proceedings of the Yamada Conference XXXXII ◽

10.1016/s0167-6881(06)80790-1 ◽

1995 ◽

pp. 281-284

Author(s):

Yasuhiro Teramoto ◽

Koichiro Nakanishi

Keyword(s):

Molecular Orientation ◽

Density Functional ◽

Density Functional Method ◽

Functional Method ◽

Liquid Interface ◽

Solid Liquid Interface ◽

Solid Liquid

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The interface of SrTiO 3 and H 2 O from density functional theory molecular dynamics

Proceedings of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rspa.2016.0293 ◽

2016 ◽

Vol 472 (2193) ◽

pp. 20160293 ◽

Cited By ~ 9

Author(s):

E. Holmström ◽

P. Spijker ◽

A. S. Foster

Keyword(s):

Molecular Dynamics ◽

Density Functional Theory ◽

Density Functional ◽

Liquid Interface ◽

Strong Suppression ◽

Electronic Density ◽

Functional Theory ◽

Degree Of Dissociation ◽

Solid Liquid Interface ◽

Solid Liquid

We use dispersion-corrected density functional theory molecular dynamics simulations to predict the ionic, electronic and vibrational properties of the SrTiO 3 /H 2 O solid–liquid interface. Approximately 50% of surface oxygens on the planar SrO termination are hydroxylated at all studied levels of water coverage, the corresponding number being 15% for the planar TiO 2 termination and 5% on the stepped TiO 2 -terminated surface. The lateral ordering of the hydration structure is largely controlled by covalent-like surface cation to H 2 O bonding and surface corrugation. We find a featureless electronic density of states in and around the band gap energy region at the solid–liquid interface. The vibrational spectrum indicates redshifting of the O–H stretching band due to surface-to-liquid hydrogen bonding and blueshifting due to high-frequency stretching vibrations of OH fragments within the liquid, as well as strong suppression of the OH stretching band on the stepped surface. We find highly varying rates of proton transfer above different SrTiO 3 surfaces, owing to differences in hydrogen bond strength and the degree of dissociation of incident water. Trends in proton dynamics and the mode of H 2 O adsorption among studied surfaces can be explained by the differential ionicity of the Ti–O and Sr–O bonds in the SrTiO 3 crystal.

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Electrochemical characterizations of darbufelone, a di-tert-butylphenol derivative, by voltammetric techniques and density functional theory calculations

Electrochimica Acta ◽

10.1016/j.electacta.2018.02.128 ◽

2018 ◽

Vol 268 ◽

pp. 462-468 ◽

Cited By ~ 3

Author(s):

Isaac Yves Lopes de Macêdo ◽

Luane Ferreira Garcia ◽

Ricardo Menegatti ◽

Freddy Fernandes Guimarães ◽

Luciano Morais Lião ◽

...

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Electrochemical Characterizations ◽

Density Functional Theory Calculations ◽

Functional Theory ◽

Voltammetric Techniques

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Data-driven simulation and characterization of gold nanoparticles melting

10.21203/rs.3.rs-677091/v1 ◽

2021 ◽

Author(s):

Claudio Zeni ◽

Kevin Rossi ◽

Theodore Pavloudis ◽

Joseph Kioseoglou ◽

Stefano de Gironcoli ◽

...

Keyword(s):

Liquid Phase ◽

Phase Change ◽

Density Functional ◽

Au Nanoparticles ◽

Density Functional Theory Calculations ◽

Data Driven ◽

Nanoparticle Melting ◽

Definition Of ◽

Dynamics Simulations ◽

Solid Liquid

Abstract We develop efficient, accurate, transferable, and interpretable machine learning force fields for Au nanoparticles, based on data gathered from Density Functional Theory calculations. We then use them to investigate the thermodynamic stability of Au nanoparticles of different sizes (1 to 6 nm), containing up to 6266 atoms, with respect to a solid-liquid phase change through molecular dynamics simulations. We predict nanoparticle melting temperatures in good agreement with respect to available experimental data. Furthermore, we characterize in detail the solid to liquid phase change mechanism employing an unsupervised learning scheme to categorize local atomic environments. We thus provide a rigorous and data-driven definition of liquid atomic arrangements in the inner and surface regions of a nanoparticle, and employ it to show that melting initiates at the outer layers.

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Formation of AlN in the N Added 18Cr Ferritic Stainless Steels

Materials Science Forum ◽

10.4028/www.scientific.net/msf.486-487.428 ◽

2005 ◽

Vol 486-487 ◽

pp. 428-431 ◽

Cited By ~ 1

Author(s):

H.C. Kim ◽

Je Hyun Lee ◽

Y.G. Heon ◽

Chang Yong Jo ◽

Jae Won Kim ◽

...

Keyword(s):

Phase Diagram ◽

Corrosion Resistance ◽

Stainless Steels ◽

Austenitic Stainless Steels ◽

Ferritic Stainless Steels ◽

The Matrix ◽

Formation Behavior ◽

Solid Liquid Interface ◽

Solid Liquid ◽

Phase Characterization

Al addition is known to enhance corrosion resistance and high temperature properties in ferritic and austenitic stainless steels. Due to the addition of Al, formation and characteristic of nitride were studied in Al added 18Cr stainless steels. The phase diagram and segregation were estimated with addition of Al in 18Cr stainless steels by the Thermo-calc program. Formation behavior of the AlN phase was studied by observing the solid/liquid interface through directional solidification and the phase characterization was performed by XRD in the extracted precipitates from the matrix. It was confirmed that the AlN phase formed at the cell boundary from the liquid in 3 and 5 wt.% Al added 18Cr stainless steels.

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The Solid-Liquid Interface: Theory and Computer Simulations

MRS Proceedings ◽

10.1557/proc-63-67 ◽

1985 ◽

Vol 63 ◽

Cited By ~ 6

Author(s):

B. B. Laird ◽

A. D. J. Haymet

Keyword(s):

Computer Simulations ◽

Density Functional ◽

Dynamic Properties ◽

Computer Experiments ◽

Liquid Interface ◽

Liquid Interfaces ◽

Functional Theory ◽

Interface Theory ◽

Solid Liquid Interface ◽

Solid Liquid

ABSTRACTWe present the results of computer simulations of body centered cubic (bcc)/melt interfaces, with particular emphasis on the “width” of the interface. Both static and dynamic properties of single crystal/liquid interfaces are examined. The implications for crystal growth near equilibrium are discussed. The results of these computer “experiments” are compared with an extended density functional theory of the solid-liquid interface.

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