Electron backscattered diffraction

Electron backscatter diffraction (EBSD) — The focused electron beam of Scanning Electron Microscopes (SEM) can be used to detect the crystallographic orientation of the top layers of a sample. The backscattered electrons (information depth 40-70 nm at 25 kV accelerating potential, lateral resolution around 200 nm) provide characteristic diffraction patterns (Kikuchi lines) on a phosphor screen. The patterns are recorded by a CCD-camera and interpreted by software. The position of the unit cell of the sample is determined by the corresponding Euler angles. In scanning mode, the software produces a surface orientation mapping that consists of... 

Ref [i] Schwartz A, Kumar M, Adams BL (2000) Electron backscatter diffraction in material science. Kluwer Plenum, New York... 

Fig. 12.9. Electron backscatter diffraction (EBSD) map showing the grain structure of a poly-Si film on glass prepared by the ALILE process (left) and the corresponding inverse pole figure showing the preferential (100) orientation of the poly-Si surface (right). The region used for the definition of the preferential (100) orientation -R(ioo) is indicated by a dashed line (20° tilt with respect to the perfect (100) orientation). The sample was annealed at 425°C for 16 h. Afterwards the Al(+Si) top layer was removed by CMP. The area under investigation was 80 x 80 pm2. Red, green and blue correspond to (100), (110) and (111), respectively, (from [39])...

Orientation imaging microscopy (OIM) maps were obtained from electron backscattering diffraction pattern (EBSP) using JEOL JXA8100 electron probe micro-analyzer with OIM software provided by TexSEM Lab., Inc. 

Bernhard Heinrich ANDREAUS, Die Polymer - Elektrolyt Brennstoffzelle — Charakter-isierung ausgewahlter Phanomene durch elektrochemische Impedanzspektroskopie, PhD-Thesis, Ecole Polytechnique Edddral Lausanne, 2002 107. U. Konig, B. Davepon, Microstructure of polycrystaUine Ti and its microelectrochemical properties by means of electron-backscattering-diffraction, Electrochim. Acta 47, 2001, 149... 

The authors would like to express their thanks to NSERC for funding this work and for scholarship support (JS). Thanks are also extended to the UBC mechanical, electronic, and glassblowing services, whose efforts have been crucial in the development of these experiments. The determination of the surface crystallography by electron-backscattered diffraction (EBSD) was performed by Prof. C. Sinclair, and creation of the stepped surface was accomplished by Dr. M. Beaudoin. 

Schwartz, A.J., Kumar, M., and Adams, B.L., Eds. (2000) Electron Backscatter Diffraction in Materials Science, Kluwer, New York. 

View/map grain orientation/crystallographic orientation and study related information like heterogeneity and microstrain in flat samples (electron backscattered diffraction). 

Electron diffraction using electron backscattered diffraction. The geometry may be different to a transmission electron microscope but the physics of Bragg diffraction is the same. 

Also electron diffraction methods like electron backscatter diffraction (EBSD) can deliver phase information (see Fig. 4). EBSD, applied in scanning electron microscopes, assigns to each surface grain its phase affiliation and its orientation as a result of detected Kikuchi diagrams during specimen scanning (Schwartz et al. 2009). Figure 4 shows an EBSD analysis result for a two-phase titanium specimen. 

Senl, 2004Sen2] SEM, TEM, electron backscattering diffraction 1 to 3 mass% Cr, CrN precipitation investigations... 

To observe the equilibrium shape of a crystal experimentally, it is necessary to confirm that the crystal one wants to observe exhibits such a shape. Since the equilibrium shape of a crystal in a matrix is the same as the equilibrium shape of the matrix entrapped within the crystal, the equilibrium crystal shape can be determined by observing the shape of the entrapped matrix. If a number of randomly oriented grains exhibit an equilibrium shape, the shape can also be determined stereographically from the crystal plane orientations of the grains and the directions of the grain interfaces on a planar section that can be obtained by the electron backscattered diffraction technique. For metals for which the anisotropy in interfacial energy is low at their processing... 

When the surfaces of the samples are crystalline, electron backscatter diffraction (EBSD) patterns, called Kikuchi lines, generated from reflected electrons, are observed. EBSD patterns provide knowledge concerning crystal stmctures and orientations. Thus, the combination of SEM and EBSD is one of the powerful tools, which can tell us the microstmctures of the sample surfaces and the orientations of the grains on the sample surfaces. 

Mor] Optical microscopy, SEM with electron backscattered diffraction pattern detector (electronography), TEM 0.2% C, Mn to 2%... 

Koblischka-Veneva A, Koblischka MR (2008) Analysis of twin boundaries using the electron backscatter diffraction (EBSD) technique. Mater Sci Eng B Solid State Mater Adv Technol 151(l) 60-64... 

Copper-based catalysts are of considerable importance for industrial reactions, e. g. partial oxidation reactions. This contribution reports on a broad study of the catalytic activity of copper in model redox reactions, e. g. methanol oxidation and oxidative coupling of methane. In addition the interaction of Cu with these reactive gases was investigated by thermoanalytic techniques (TG/DTA, DSC), temperature programmed oxidation and reduction (TPO/tpR) and thermal desorption spectroscopy (TDS). Scanning electron microscopy (SEM) and electron backscattering diffraction (EBSD) was additionally used to characterise the copper catalyst before and after catalytic action. 

FIGURE 3.18 Electron backscatter diffraction Image of a fatigue crack In alloy X. Bar Is 200 pm. Colors represent specific crystal orientations. SOURCE Courtesy of J. Burns and M. Frary, Boise State University, from J. Burns, Fligh Temperature Fatigue Crack Growth Behavior and Microstructural Evolution in Alloy 230, M.S. thesis, Boise State University, 2010. 

CONTEXT X-ray diffraction is the most common method for determining molecular structures within a crystal, but other methods are capable of faster, less detailed information about the crystal. For example, electron backscatter diffraction (also called backscatter Kikuchi diffraction), from a scanning electron microscope, measures the diffraction patterns of electrons that scatter off more than one plane in the crystal. From the patterns, the crystallographic point group, the orientation of the crystal, and the exposed Miller indices of the surface can be determined. Copper crystals, which have the advantage of simple structure, have been used to test the strengths and limitations of this method. 

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