scholarly journals Deformation mechanism of neutron irradiated Al-B based on SEM-DIC

2022 ◽  
Vol 355 ◽  
pp. 01004
Author(s):  
Jiaqi Xiang ◽  
Qijie Feng ◽  
Junchao Cheng ◽  
Lei Lu ◽  
Junyu Huang ◽  
...  
Keyword(s):  
Slip Band ◽  
Electron Backscatter Diffraction ◽  
Image Correlation ◽  
High Concentration ◽  
Helium Bubbles ◽  
Band Area ◽  
Transmission Electron ◽  
Before And After ◽  
Backscatter Diffraction

The electron backscatter diffraction (EBSD) characterization of irradiated Al-B shows that there is a high concentration defect region around the borides. Nanoscale speckle particles were successfully prepared on the surface of Al-B before and after irradiation, and then the mesoscale strain during in-situ deformation was obtained by digital image correlation (DIC) technique. The results shows that slip band bypass such an area through cross slips with slip band deflection. Transmission electron microscopy (TEM) indicates that abundant helium bubbles exist in the deflected slip band area pinning the dislocations.

Creep Deformation Microstructures in DS Nb-Hf-Ti-Si In-Situ Composites

1999 ◽  
Vol 5 (S2) ◽  
pp. 258-259
Author(s):  
S.D. Sitzman ◽  
B.P. Bewlay
Keyword(s):  
Creep Deformation ◽  
Microprobe Analysis ◽  
Electron Backscatter Diffraction ◽  
Czochralski Method ◽  
Directionally Solidified ◽  
Creep Tests ◽  
In Situ Composites ◽  
Before And After ◽  
Backscatter Diffraction

Directionally solidified (DS) in-situ composites based on (Nb) and (Nb) silicides, such as Nb5Si3 and Nb3Si, are presently under investigation as high-temperature structural materials [1, 2]. Alloying additions of elements such as Hf, Ti and Mo to these silicides are also being explored. The present paper describes the microstructure of a DS Nb-silicide based composite before and after creep deformation.Alloys were prepared from high purity elements (>99.9%) using induction levitation melting in a segmented water-cooled copper crucible. The alloys were directionally solidified using the Czochralski method [2]. Creep tests were conducted at 1200°C to 50% deformation. Characterization was performed using scanning electron microscopy, electron microprobe analysis (EMPA), and electron backscatter diffraction pattern analysis (EBSP).

scholarly journals Reveal Hydrogen Behavior at Grain Boundaries in Fe–22Mn–0.6C TWIP Steel via In Situ Micropillar Compression Test

2022 ◽  
Author(s):  
Xu Lu ◽  
Dong Wang ◽  
Di Wan ◽  
Xiaofei Guo ◽  
Roy Johnsen
Keyword(s):  
Grain Boundaries ◽  
Compression Test ◽  
Electron Backscatter Diffraction ◽  
Scanning Transmission Electron Microscope ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Micropillar Compression ◽  
Backscatter Diffraction ◽  
Boundary Intersections

AbstractIn this study, the effect of hydrogen on dislocation and twinning behavior along various grain boundaries in a high-manganese twinning-induced plasticity steel was investigated using an in situ micropillar compression test. The compressive stress in both elastic and plastic regimes was increased with the presence of hydrogen. Further investigation by transmission electron backscatter diffraction and scanning transmission electron microscope demonstrated that hydrogen promoted both dislocation multiplication and twin formation, which resulted in higher stress concentration at twin–twin and twin–grain boundary intersections.

Orientation and Microstructure Dependence of Electromigration Damage in Damascene Cu Interconnect Lines

2005 ◽  
Vol 495-497 ◽  
pp. 1443-1448 ◽  
Author(s):  
Kabir Kumar Mirpuri ◽  
Jerzy A. Szpunar
Keyword(s):  
Electron Backscatter Diffraction ◽  
Orientation Dependence ◽  
In Situ Monitoring ◽  
Cu Interconnects ◽  
Electron Backscatter ◽  
Before And After ◽  
Cu Interconnect ◽  
Interconnect Lines ◽  
Backscatter Diffraction

In the present paper we report the texture and microstructure dependence of electromigration damage in Cu interconnects. This was made possible by ncorporating a sophisticated set of instrumentation within the SEM which enabled in-situ monitoring of the electromigration defects. The electron backscatter diffraction (EBSD) maps were obtained before and after the completion of the electromigration tests. Thus, by comparing the maps before and after the failure it was possible to associate the texture and microstructure with both failure sites - voids and hillocks. Results from lines down to 130 nm are included and orientation dependence of the defects is discussed.

High-temperature oxidation of CoGa: Influence of the crystallographic orientation on the oxidation rate

2002 ◽  
Vol 17 (10) ◽  
pp. 2489-2498 ◽  
Author(s):  
U. Koops ◽  
D. Hesse ◽  
M. Martin
Keyword(s):  
High Temperature ◽  
Crystallographic Orientation ◽  
High Temperature Oxidation ◽  
Elevated Temperatures ◽  
Electron Backscatter Diffraction ◽  
Ex Situ ◽  
Temperature Oxidation ◽  
Transmission Electron ◽  
Backscatter Diffraction

The crystallographic orientation plays an important role in high-temperature oxidation of the intermetallic compound CoGa. When CoGa is exposed to air at elevated temperatures, the oxide β–Ga2O3 is formed, and different scale growth rates are observed, depending on the crystallographic orientation of the CoGa grains. This dependence is a consequence of the anisotropy of the gallium diffusion rate through the β–Ga2O3 scale and of a topotaxial orientation relationship occurring between β–Ga2O3 and CoGa. The combination of ex situ techniques, such as transmission electron microscopy and electron backscatter diffraction with optical microscopy, applied in situ resulted in a thorough understanding of these relations and of the oxidation process in general.

Effect of Annealing on Microstructural Development and Grain Orientation in Electrodeposited Ni

2010 ◽  
Vol 160 ◽  
pp. 235-240 ◽  
Author(s):  
Uta Klement ◽  
L. Hollang ◽  
S.R. Dey ◽  
M. Battabyal ◽  
O.V. Mishin ◽  
...  
Keyword(s):  
Grain Growth ◽  
Cross Sections ◽  
Electron Backscatter Diffraction ◽  
Microstructural Development ◽  
Growth Behaviour ◽  
Coalescence Model ◽  
Transmission Electron ◽  
Columnar Grains ◽  
Backscatter Diffraction

Thick (up to 5 mm) Ni electrodeposits were produced by the pulsed electrodeposition (PED) technique. The PED-Ni was investigated in planar and cross-sections using high resolution scanning electron microscopy. Grain size and local texture were studied by electron backscatter diffraction. Thermal stability and grain growth behaviour were investigated using in-situ annealing in the transmission electron microscope. It is observed that columnar grains are present in the material and that the orientation of grains is not uniform. Textures and in-situ annealing behaviour are compared to previous data on nanocrystalline PED-Ni and Ni-Fe, where a subgrain coalescence model adopted from recrystallization is used to describe the occurrence of abnormal grain growth upon annealing and where twinning was found to be responsible for the texture development.

scholarly journals In-Situ TEM Annealing Observation of Helium Bubble Evolution in Pre-Irradiated FeCoNiCrTi0.2 Alloys

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3727
Author(s):  
Huanhuan He ◽  
Zhiwei Lin ◽  
Shengming Jiang ◽  
Xiaotian Hu ◽  
Jian Zhang ◽  
...  
Keyword(s):  
Vacuum Arc ◽  
In Situ Tem ◽  
Face Centered Cubic ◽  
Helium Bubble ◽  
High Entropy ◽  
Helium Bubbles ◽  
Transmission Electron ◽  
Bubble Evolution ◽  
Face Centered

The FeCoNiCrTi0.2 high-entropy alloys fabricated by vacuum arc melting method, and the annealed pristine material, are face centered cubic structures with coherent γ’ precipitation. Samples were irradiated with 50 keV He+ ions to a fluence of 2 × 1016 ions/cm2 at 723 K, and an in situ annealing experiment was carried out to monitor the evolution of helium bubbles during heating to 823 and 923 K. The pristine structure of FeCoNiCrTi0.2 samples and the evolution of helium bubbles during in situ annealing were both characterized by transmission electron microscopy. The annealing temperature and annealing time affect the process of helium bubbles evolution and formation. Meanwhile, the grain boundaries act as sinks to accumulate helium bubbles. However, the precipitation phase seems have few effects on the helium bubble evolution, which may be due to the coherent interface and same structure of γ’ precipitation and matrix.

Where are the geometrically necessary dislocations accommodating small imprints?

2009 ◽  
Vol 24 (3) ◽  
pp. 647-651 ◽  
Author(s):  
M. Rester ◽  
C. Motz ◽  
R. Pippan
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Twin Boundary ◽  
Crystal Orientation ◽  
Electron Backscatter Diffraction ◽  
Transmission Electron ◽  
Electron Backscatter ◽  
Copper Single Crystals ◽  
Backscatter Diffraction ◽  
Small Misorientation

Electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM) analyses of small indentations in copper single crystals exhibit only slight changes of the crystal orientation in the surroundings of the imprints. Far-reaching dislocations might be the reason for these small misorientation changes. Using EBSD and TEM technique, this work makes an attempt to visualize the far-propagating dislocations by introducing a twin boundary in the vicinity of small indentations. Because dislocations piled up at the twin boundary produce a misorientation gradient, the otherwise far-propagating dislocations can be detected.

Orientation relationships of carlsbergite in schreibersite and kamacite in the north Chile iron meteorite

2006 ◽  
Vol 70 (4) ◽  
pp. 373-382 ◽  
Author(s):  
G. Nolze ◽  
G. Wagner ◽  
R. Saliwan Neumann ◽  
R. Skála ◽  
V. Geist
Keyword(s):  
Electron Backscatter Diffraction ◽  
Metallic Matrix ◽  
Iron Meteorite ◽  
Orientation Relationships ◽  
Orientation Relation ◽  
Crystalline Materials ◽  
The North ◽  
Transmission Electron ◽  
Backscatter Diffraction ◽  
General Connection

AbstractThe crystallographic orientation of carlsbergite (CrN) in the north Chile meteorite (hexahedrite) was investigated using electron backscatter diffraction and transmission electron microscopy. These studies examined the CrN crystals in the rhabdites (idiomorphic schreibersite) and in kamacite. It was found that the CrN crystals embedded in rhabdite show a number of different orientation relationships with the host crystals. These orientations can be explained based on the lattice dimensions of both coexisting crystalline materials. It was also found that both carlsbergite and kamacite are characterized by a high dislocation density (≥ l09 cm-2) while rhabdite is free of dislocations. It is supposed that in spite of the deformed metallic matrix, a general connection between the orientation relation of all the phases involved exists.

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