Determining Grain Boundary Position and Geometry from EBSD Data: Limits of Accuracy

2021 ◽  
pp. 1-13
Author(s):  
David T. Fullwood ◽  
Sarah Sanderson ◽  
Sterling Baird ◽  
Jordan Christensen ◽  
Eric R. Homer ◽  
...  
Keyword(s):  
Electron Backscatter Diffraction ◽  
Finite Size ◽  
Sample Surface ◽  
Accurate Method ◽  
Crystalline Materials ◽  
Backscattered Electrons ◽  
Ebsd Data ◽  
Subsurface Geometry ◽  
Backscatter Diffraction ◽  
Transition Curves

As the feature size of crystalline materials gets smaller, the ability to correctly interpret geometrical sample information from electron backscatter diffraction (EBSD) data becomes more important. This paper uses the notion of transition curves, associated with line scans across grain boundaries (GBs), to correctly account for the finite size of the excitation volume (EV) in the determination of the geometry of the boundary. Various metrics arising from the EBSD data are compared to determine the best experimental proxy for actual numbers of backscattered electrons that are tracked in a Monte Carlo simulation. Consideration of the resultant curves provides an accurate method of determining GB position (at the sample surface) and indicates a significant potential for error in determining GB position using standard EBSD software. Subsequently, simple criteria for comparing experimental and simulated transition curves are derived. Finally, it is shown that the EV is too shallow for the curves to reveal subsurface geometry of the GB (i.e., GB inclination angle) for most values of GB inclination.

Electron-Backscatter Diffraction of Photovoltaic Thin Films

2007 ◽  
Vol 1012 ◽  
Author(s):  
Helio Moutinho ◽  
Ramesh Dhere ◽  
Chun-Sheng Jiang ◽  
Bobby To ◽  
Mowafak Al-Jassim
Keyword(s):  
Electron Backscatter Diffraction ◽  
Ion Beam ◽  
Surface Damage ◽  
Sample Surface ◽  
Force Microscopy ◽  
Atomic Force ◽  
Ebsd Data ◽  
Electron Backscatter ◽  
Backscatter Diffraction

AbstractIn electron-backscatter diffraction, crystalline orientation maps are formed while the electron beam of an SEM scans the sample surface. EBSD requires a flat sample to avoid shadowing of the electrons from the detector by surface features. In this work, we investigate the preparation of CdTe samples deposited by close-spaced sublimation for EBSD analysis. Untreated samples were rough, resulting in areas with no EBSD signal. We processed the samples by polishing and ion-beam milling. Polishing produced flat samples, but low-quality EBDS data, because the top surface of the samples had poor crystallinity. In contrast, ion-beam milling proved to be suitable for producing flat samples with minimal surface damage, yielding good EBSD data. We also analyzed the samples with atomic force microscopy, and correlated the quality of the EBSD data with sample roughness. The EBSD data showed that the CdTe films were randomly oriented and had columnar growth and a high density of <111> twin boundaries.

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.

scholarly journals Validation of three-dimensional diffraction contrast tomography reconstructions by means of electron backscatter diffraction characterization

2013 ◽  
Vol 46 (4) ◽  
pp. 1145-1150 ◽  
Author(s):  
Melanie Syha ◽  
Andreas Trenkle ◽  
Barbara Lödermann ◽  
Andreas Graff ◽  
Wolfgang Ludwig ◽  
...  
Keyword(s):  
Electron Backscatter Diffraction ◽  
Three Dimensional ◽  
Data Reconstruction ◽  
Characterization Methods ◽  
Diffraction Contrast ◽  
Ebsd Data ◽  
Electron Backscatter ◽  
Backscatter Diffraction ◽  
Tomography Data ◽  
Good Agreement

Microstructure reconstructions resulting from diffraction contrast tomography data of polycrystalline bulk strontium titanate were reinvestigated by means of electron backscatter diffraction (EBSD) characterization. Corresponding two-dimensional grain maps from the two characterization methods were aligned and compared, focusing on the spatial resolution at the internal interfaces. The compared grain boundary networks show a remarkably good agreement both morphologically and in crystallographic orientation. Deviations are critically assessed and discussed in the context of diffraction data reconstruction and EBSD data collection techniques.

scholarly journals Optimizing Electron Backscatter Diffraction of Carbonate Biominerals—Resin Type and Carbon Coating

2009 ◽  
Vol 15 (3) ◽  
pp. 197-203 ◽  
Author(s):  
Alberto Pérez-Huerta ◽  
Maggie Cusack
Keyword(s):  
Carbon Coating ◽  
Blue Mussel ◽  
Electron Backscatter Diffraction ◽  
Diffraction Intensity ◽  
Ebsd Data ◽  
Electron Backscatter ◽  
Different Types ◽  
The Common ◽  
Biogenic Carbonates ◽  
Backscatter Diffraction

AbstractElectron backscatter diffraction (EBSD) is becoming a widely used technique to determine crystallographic orientation in biogenic carbonates. Despite this use, there is little information available on preparation for the analysis of biogenic carbonates. EBSD data are compared for biogenic aragonite and calcite in the common blue mussel, Mytilus edulis, using different types of resin and thicknesses of carbon coating. Results indicate that carbonate biomineral samples provide better EBSD results if they are embedded in resin, particularly epoxy resin. A uniform layer of carbon of 2.5 nm thickness provides sufficient conductivity for EBSD analyses of such insulators to avoid charging without masking the diffracted signal. Diffraction intensity decreases with carbon coating thickness of 5 nm or more. This study demonstrates the importance of optimizing sample preparation for EBSD analyses of insulators such as carbonate biominerals.

Influence of Temperature upon the Texture Evolution and Mechanical Behaviour of Zircaloy-4

2011 ◽  
Vol 702-703 ◽  
pp. 834-837
Author(s):  
Peter Honniball ◽  
Michael Preuss ◽  
Joao Quinta da Fonseca
Keyword(s):  
Mechanical Behaviour ◽  
Room Temperature ◽  
Electron Backscatter Diffraction ◽  
Texture Evolution ◽  
Crystal Plasticity Finite Element ◽  
Ebsd Data ◽  
Electron Backscatter ◽  
Different Temperatures ◽  
Increasing Temperature ◽  
Backscatter Diffraction

The mechanical behaviour and texture evolution during uniaxial compression of Zircaloy-4 at different temperatures (25, 300, 500 C) has been studied. At room temperature and 300 C the texture evolution and strain-hardening behaviour observed are attributed to the activation of {10-12} tensile twinning, which can be identified in optical micrographs and electron backscatter diffraction (EBSD) data. The influence of twinning upon the texture evolution and hardening rate becomes less apparent with increasing temperature. Nevertheless twinning is still active at 500 C. Simulation of the texture evolution at 500 C using crystal plasticity finite element modelling (CPFEM) indicates that slip alone cannot explain the experimentally observed textures at this temperature.

Analysing crystal distortions to deduce dislocation slip systems

2021 ◽  
Author(s):  
John Wheeler ◽  
Sandra Piazolo ◽  
David Prior ◽  
Jake Tielke ◽  
Pat Trimby
Keyword(s):  
Electron Backscatter Diffraction ◽  
Direct Method ◽  
Grain Boundary Sliding ◽  
Dislocation Creep ◽  
Dislocation Slip ◽  
Slip Systems ◽  
Crystalline Materials ◽  
Burgers Vector ◽  
Growth Defects ◽  
Backscatter Diffraction

&lt;p&gt;In many parts of the Earth rocks deform by dislocation creep. There is therefore a need to understand which slip systems operated in nature and in experimental products. Knowing the conditions of experiments may then allow natural conditions and strain rates to be characterised. Dislocation creep typically gives lattice preferred orientations (LPOs), since activity on particular slip systems leads to lattice rotations and alignment. For decades LPOs, measured first optically and since the 1990s by EBSD, have been used to infer slip systems. This is a valuable technique but the link between slip sytem activity and LPO is complicated, especially if recrystallisation and/or grain boundary sliding have been involved.&lt;/p&gt;&lt;p&gt;Here we present a more direct method to deduce &amp;#8220;geometrically necessary&amp;#8221; dislocations (GNDs) from the distortions within crystals. Distortions may be optically visible (e.g. undulose extinction in quartz) but EBSD has revealed how common distortions are, and allowed them to be quantified. The method does not give the complete picture of GNDs but allows hypotheses to be tested about possible slip systems. We illustrate this &amp;#8220;Weighted Burgers Vector&amp;#8221; method with a number of examples. In olivine the method distinguishes slip parallel to a and c, and in plastically deformed plagioclase it reveals a variety of slip systems which would be difficuilt to deduce from LPOs alone. GNDs may not necessarily reflect the full slip system activity, since many dislocations will have passed through crystals and merged with grain boundaries leaving no signature. Neverthless the method highlights what dislocations are present &amp;#8220;stranded&amp;#8221; in the microstructure. In many case these will have been produced by deformation although the method can also characterise growth defects.&lt;/p&gt;&lt;p&gt;Wheeler et al. 2009. The weighted Burgers vector: a new quantity for constraining dislocation densities and types using electron backscatter diffraction on 2D sections through crystalline materials. &lt;span&gt;DOI:&lt;/span&gt;&amp;#160;10.1111/j.1365-2818.2009.03136.x&lt;/p&gt;

A 3D FIB Investigation of Dynamic Recrystallization in a Cu-Sn Bronze

2012 ◽  
Vol 715-716 ◽  
pp. 498-501 ◽  
Author(s):  
Ali Gholinia ◽  
Ian Brough ◽  
John F. Humphreys ◽  
Pete S. Bate
Keyword(s):  
Dynamic Recrystallization ◽  
Focused Ion Beam ◽  
Electron Backscatter Diffraction ◽  
Ion Beam ◽  
Bronze Alloy ◽  
Ebsd Data ◽  
Nucleation Sites ◽  
Electron Backscatter ◽  
Backscatter Diffraction ◽  
Relationship Of

A combination of electron backscatter diffraction (EBSD) and focused ion beam (FIB) techniques were used to obtain 3D EBSD data in an investigation of dynamic recrystallization in a Cu-2%Sn bronze alloy. The results of this investigation show the origin of the nucleation sites for dynamic recrystallization and also elucidates the orientation relationship of the recrystallized grains to the deformed, prior grains and between the dynamically recrystallized grains.

Comparison of electron backscatter and X-ray diffraction techniques for measuring dislocation density in Zircaloy-2

2019 ◽  
Vol 52 (2) ◽  
pp. 415-427 ◽  
Author(s):  
T. Skippon ◽  
L. Balogh ◽  
M. R. Daymond
Keyword(s):  
Dislocation Density ◽  
Electron Backscatter Diffraction ◽  
Profile Analysis ◽  
Line Profile Analysis ◽  
X Ray Diffraction ◽  
Density Measurements ◽  
X Ray ◽  
Ebsd Data ◽  
Electron Backscatter ◽  
Backscatter Diffraction

Two methods for measuring dislocation density were applied to a series of plastically deformed tensile samples of Zircaloy-2. Samples subjected to plastic strains ranging from 4 to 17% along a variety of loading paths were characterized using both electron backscatter diffraction (EBSD) and synchrotron X-ray line profile analysis (LPA). It was found that the EBSD-based method gave results which were similar in magnitude to those obtained by LPA and followed a similar trend with increasing plastic strain. The effects of microscope parameters and post-processing of the EBSD data on dislocation density measurements are also discussed. The typical method for estimating uncertainty in dislocation density measured via EBSD was shown to be overly conservative, and a more realistic method of determining uncertainty is presented as an alternative.

Sign in / Sign up

Export Citation Format

Share Document