Atomic structure of Σ7(0112) symmetrical tilt grain boundaries in α-Al2O3

Very few electron microscopy papers have been published on the atomic structure of the copper oxide based superconductor surfaces. Zandbergen et al. have reported that the surface of YBa2Cu3O7-δ was such that the terminating layer sequence is bulk-Y-CuO2-BaO-CuO-BaO, whereas the interruption at the grain boundaries is bulk-Y-CuO2-BaO-CuO. Bursill et al. reported that HREM images of the termination at the surface are in good agreement with calculated images with the same layer sequence as observed by Zandbergen et al. but with some oxygen deficiency in the two surface layers. In both studies only one or a few surfaces were studied.

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Morphology and atomic structure of segregated grain boundaries in Cu-Sb

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100121673 ◽

1992 ◽

Vol 50 (1) ◽

pp. 254-255

Author(s):

R. W. Fonda ◽

D. E. Luzzi

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Intergranular Fracture ◽

Atomic Structure ◽

Copper Alloys ◽

Polycrystalline Materials ◽

Grain Boundary Embrittlement ◽

Boundary Embrittlement

The properties of polycrystalline materials are strongly dependant upon the strength of internal boundaries. Segregation of solute to the grain boundaries can adversely affect this strength. In copper alloys, segregation of either bismuth or antimony to the grain boundary will embrittle the alloy by facilitating intergranular fracture. Very small quantities of bismuth in copper have long been known to cause severe grain boundary embrittlement of the alloy. The effect of antimony is much less pronounced and is observed primarily at lower temperatures. Even though moderate amounts of antimony are fully soluble in copper, concentrations down to 0.14% can cause grain boundary embrittlement.

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Atomic structure of [0001]-tilt grain boundaries in ZnO: A high-resolution TEM study of fiber-textured thin films

Physical Review B ◽

10.1103/physrevb.70.125415 ◽

2004 ◽

Vol 70 (12) ◽

Cited By ~ 53

Author(s):

Fumiyasu Oba ◽

Hiromichi Ohta ◽

Yukio Sato ◽

Hideo Hosono ◽

Takahisa Yamamoto ◽

...

Keyword(s):

Thin Films ◽

High Resolution ◽

Grain Boundaries ◽

Atomic Structure ◽

High Resolution Tem

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Atomic structure of grain boundaries in UO2 Bicrystals: A coupled high resolution transmission electron Microscopy/Atomistic simulation approach

Scripta Materialia ◽

10.1016/j.scriptamat.2021.114191 ◽

2022 ◽

Vol 206 ◽

pp. 114191

Author(s):

Emeric Bourasseau ◽

Claire Onofri ◽

Amani Ksibi ◽

Xavière Iltis ◽

Renaud C. Belin ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

High Resolution ◽

Grain Boundaries ◽

Atomic Structure ◽

Atomistic Simulation ◽

Simulation Approach ◽

Transmission Electron

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Structure and Stability of Grain Boundaries in Molybdenum with Segregated Carbon Impurities

MRS Proceedings ◽

10.1557/proc-578-405 ◽

1999 ◽

Vol 578 ◽

Cited By ~ 1

Author(s):

R. Janisch ◽

T. Ochs ◽

A. Merkle ◽

C. Elsässer

Keyword(s):

Ab Initio ◽

Grain Boundaries ◽

Density Functional ◽

Local Density ◽

Structural Parameters ◽

Carbide Phases ◽

Carbon Impurities ◽

Transmission Electron ◽

Local Density Functional Theory ◽

Symmetrical Tilt

AbstractThe segregation of interstitial impurities to symmetrical tilt grain boundaries (STGB) in bodycentered cubic transition metals is studied by means of ab-initio electronic-structure calculations based on the local density functional theory (LDFT). Segregation energies as well as changes in atomic and electronic structures at the ΣE5 (310) [001] STGB in Mo caused by segregated interstitial C atoms are investigated. The results are compared to LDFT data obtained previously for the pure Σ5 (310) [001] STGB in Mo. Energetic stabilities and structural parameters calculated ab initio for several crystalline Molybdenum Carbide phases with cubic, tetragonal or hexagonal symmetries and different compositions, MoCx, are reported and compared to recent high-resolution transmission electron microscopy (HRTEM) observations of MoCx, intergranular films and precipitates formed by C segregation to a Σ5 (310) [001] STGB in a Mo bicrystal.

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