Analysis of Oxygen Vacancy Trapping at [001] Symmetric Tilt Grain Boundaries in Barium Titanate by Atomistic Simulations

The role of grain boundaries (GBs) in the diffusion of oxygen vacancies (VO••s) in barium titanate (BaTiO3) and its mechanism were investigated using atomistic simulation techniques. It was found that GBs trapped VO••s at specific sites in the course of the diffusion, and the excess energy reflecting structural distortion of the GB was closely related to the availability of the trapping. GBs therefore act as a resistance of the diffusion of VO••s, suggesting that electrical degradation of multilayer ceramic capacitors (MLCCs), which is derived from vacancy diffusion, enables to be additionally improved by controlling GB structures in BaTiO3-based dielectrics.

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Atomistic Simulations of [001] Symmetric Tilt Boundaries in Ni3Al

MRS Proceedings ◽

10.1557/proc-81-45 ◽

1986 ◽

Vol 81 ◽

Cited By ~ 11

Author(s):

S. P. Chen ◽

A. F. Voter ◽

D. J. Srolovitz

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Simulation Study ◽

Atomistic Simulation ◽

Atomistic Simulations ◽

Boundary Composition ◽

Symmetric Tilt ◽

Tilt Boundaries ◽

Cohesive Energies

AbstractWe report a systematic atomistic simulation study of [001] symmetric tilt grain boundaries (GB) in Ni3Al, Ni, and Al. We found that the grain boundary energies and cohesive energies of Ni3Al and pure fcc Ni are approximately thesame. Grain boundary energies aid cohesive energies in Ni3Al depends stronglyon the grain boundary composition. The Al-rich boundaries have highest grain boundary energies and lowest cohesive energies. This offers an explanation for the stoichiometric effect on the boron ductilization

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ATOMISTIC SIMULATIONS OF [100], [110] AND [111] SYMMETRIC TILT GRAIN BOUNDARIES IN Ni3Al

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1990135 ◽

1990 ◽

Vol 51 (C1) ◽

pp. C1-227-C1-232

Author(s):

D. T.L. LIN ◽

D. CHEN

Keyword(s):

Grain Boundaries ◽

Atomistic Simulations ◽

Symmetric Tilt

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Local phenomena at grain boundaries: An alternative approach to grasp the role of oxygen vacancies in metallization of VO2

Journal of Materiomics ◽

10.1016/j.jmat.2018.09.003 ◽

2018 ◽

Vol 4 (4) ◽

pp. 360-367 ◽

Cited By ~ 3

Author(s):

Wanheng Lu ◽

Lai-Mun Wong ◽

Shijie Wang ◽

Kaiyang Zeng

Keyword(s):

Grain Boundaries ◽

Oxygen Vacancies ◽

Alternative Approach

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Atomistic simulations on intergranular fracture toughness of copper bicrystals with symmetric tilt grain boundaries

Metals and Materials International ◽

10.1007/s12540-017-7307-3 ◽

2018 ◽

Vol 24 (1) ◽

pp. 35-41 ◽

Cited By ~ 2

Author(s):

Cheng Bin Cui ◽

Hyeon Gyu Beom

Keyword(s):

Fracture Toughness ◽

Grain Boundaries ◽

Intergranular Fracture ◽

Atomistic Simulations ◽

Symmetric Tilt

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Molecular dynamics study of the role of symmetric tilt grain boundaries on the helium distribution in nickel

Journal of Nuclear Materials ◽

10.1016/j.jnucmat.2018.01.046 ◽

2018 ◽

Vol 502 ◽

pp. 86-94 ◽

Cited By ~ 6

Author(s):

E. Torres ◽

J. Pencer

Keyword(s):

Molecular Dynamics ◽

Grain Boundaries ◽

Symmetric Tilt

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Electric transport properties of rare earth doped YbxCa1-xMnO3 ceramics (part II: The role of grain boundaries and oxygen vacancies)

Journal of the European Ceramic Society ◽

10.1016/j.jeurceramsoc.2019.07.017 ◽

2019 ◽

Vol 39 (15) ◽

pp. 4800-4805 ◽

Cited By ~ 1

Author(s):

Meimanat Rahmani ◽

Christian Pithan ◽

Rainer Waser

Keyword(s):

Rare Earth ◽

Grain Boundaries ◽

Transport Properties ◽

Oxygen Vacancies ◽

Electric Transport ◽

Rare Earth Doped

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Quantifying the energetics and length scales of carbon segregation toα-Fe symmetric tilt grain boundaries using atomistic simulations

Modelling and Simulation in Materials Science and Engineering ◽

10.1088/0965-0393/21/3/035009 ◽

2013 ◽

Vol 21 (3) ◽

pp. 035009 ◽

Cited By ~ 39

Author(s):

N R Rhodes ◽

M A Tschopp ◽

K N Solanki

Keyword(s):

Grain Boundaries ◽

Atomistic Simulations ◽

Length Scales ◽

Carbon Segregation ◽

Symmetric Tilt

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Investigation of the Sintering Behavior of Ultrapure α-Alumina Containing Low Amounts of SiO2 or CaO

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.317-318.1 ◽

2006 ◽

Vol 317-318 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Nicolas Louet ◽

Thierry Epicier ◽

Gilbert Fantozzi

Keyword(s):

Grain Boundaries ◽

Grain Growth ◽

Oxygen Vacancies ◽

Glassy Phase ◽

Intermediate Stage ◽

Abnormal Grain Growth ◽

Sintering Behavior ◽

Critical Temperatures ◽

Heterogeneous Microstructures

The target of this work is to investigate the effect of small additions of SiO2 or CaO on the sintering behavior and the microstructure of an ultrapure α-alumina compound. The sintering behavior has been investigated through extensive dilatometric study. SiO2 additions lead to a significant decrease in shrinkage rate during the intermediate stage of sintering whereas CaO is beneficent to densification. It has been found that during this stage which corresponds to the maximum of densification rate, grain boundaries diffusion controls densification through oxygen vacancies. The study of the densification behavior under different atmospheres help us to explain the role of the additives in agreement with electroneutrality equations. S.E.M. investigations confirm the well know correlation between doping and heterogeneous microstructures. After doping with SiO2 or CaO, abnormal grain growth appears at temperatures corresponding to the lowest eutectics given by Al2O3-SiO2 or Al2O3-CaO phase diagrams. H.R.T.E.M. observations show that below the critical temperatures for abnormal grain growth, additives enrichment is observed near grain boundaries (GBs). Above these temperatures, glassy phase for SiO2-doping and calciumhexaluminate (CA6) for CaO-doping are present at grain boundaries.

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