Electron channelling contrast imaging (ECCI) applied to a fresnoite dendrite grown via electrochemically induced nucleation

In the 1970s there was considerable interest in the development of the electron channelling contrast imaging (ECCI) technique for imaging near surface defects in bulk (electron opaque) specimens. The predictions of the theories were realised experimentally by Morin et al., who used a field emission gun (FEG) operating at 40-50kV and an energy filter such that only electrons which had lost no more than a few 100V were detected. This paper presents the results of a set of preliminary experiments which show that an energy filter system is unneccessary to image and characterise the Burgers vectors of dislocations in bulk specimens. The examples in the paper indicatethe general versatility of the technique.A VG HB501 STEM with a FEG was operated at 100kV. A single tilt cartridge was used in the reflection position of the microscope. A retractable back-scattered electron detector was fitted into the secondary electron port and positioned to within a few millimetres of the specimen. The image was acquired using a Synoptics Synergy framestore and digital scan generator and subsequently processed using Semper 6. The beam divergence with the specimen in this position was 2.5 mrads with a spot size of approximately 4nm. Electron channelling patterns were used to orientate the sample.

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Novel −75°C SEM cooling stage: application for martensitic transformation in steel

Microscopy ◽

10.1093/jmicro/dfaa051 ◽

2020 ◽

Author(s):

Kaneaki Tsuzazki ◽

Motomichi Koyama ◽

Ryosuke Sasaki ◽

Keiichiro Nakafuji ◽

Kazushi Oie ◽

...

Keyword(s):

Martensitic Transformation ◽

Electron Backscatter Diffraction ◽

Dislocation Slip ◽

In Situ Observation ◽

Contrast Imaging ◽

Cooling Stage ◽

Electron Channelling ◽

Electron Backscatter ◽

Backscatter Diffraction

Abstract Microstructural changes during the martensitic transformation from face-centred cubic (FCC) to body-centred cubic (BCC) in an Fe-31Ni alloy were observed by scanning electron microscopy (SEM) with a newly developed Peltier stage available at temperatures to −75°C. Electron channelling contrast imaging (ECCI) was utilized for the in situ observation during cooling. Electron backscatter diffraction analysis at ambient temperature (20°C) after the transformation was performed for the crystallographic characterization. A uniform dislocation slip in the FCC matrix associated with the transformation was detected at −57°C. Gradual growth of a BCC martensite was recognized upon cooling from −57°C to −63°C.

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Fatigue Life Enhancement by Surface Coating of Ni/Cu Multilayered Films

Materials Science Forum ◽

10.4028/www.scientific.net/msf.561-565.2393 ◽

2007 ◽

Vol 561-565 ◽

pp. 2393-2398 ◽

Cited By ~ 4

Author(s):

Yoshihisa Kaneko ◽

Y. Nishijima ◽

T. Sanda ◽

Satoshi Hashimoto

Keyword(s):

Fatigue Life ◽

Individual Component ◽

Nickel Coating ◽

Multilayer Coating ◽

Fatigue Tests ◽

Contrast Imaging ◽

Multilayered Films ◽

Electron Channelling ◽

Life Enhancement ◽

Fatigue Life Enhancement

Effect of Ni/Cu multilayer coating on fatigue durability was investigated. The Ni/Cu multilayered films were coated on cylindrical copper specimens by electroplating technique. Thickness of individual component layers was h=20nm and 100nm and the total thickness was 5μm. The specimens with a conventional nickel coating and uncoated specimens were also prepared. Push-pull fatigue tests were carried out in air at room temperature. It was found that the specimens with the Ni/Cu multilayered coatings exhibited the fatigue lives longer than those of the conventional nickel coating. In particular, the fatigue life with the h=100nm multilayer was at least ten times longer than that with the nickel coating at the stress amplitude of 90MPa. From the electron channelling contrast imaging (ECCI) observation of subsurface areas of the copper specimens, dislocation structures peculiar to fatigue deformation was suppressed by the surface coatings.

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Electron Channelling Contrast Imaging (ECCI)

10.14293/s2199-1006.1.sor-matsci.cl5ddh3.v1 ◽

2018 ◽

Author(s):

Angus Wilkinson

Keyword(s):

Contrast Imaging ◽

Electron Channelling

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Characterisation of nitride thin films by electron backscatter diffraction and electron channelling contrast imaging

Materials Science and Technology ◽

10.1179/174328406x130957 ◽

2006 ◽

Vol 22 (11) ◽

pp. 1352-1358 ◽

Cited By ~ 4

Author(s):

C. Trager-Cowan ◽

F. Sweeney ◽

A. Winkelmann ◽

A. J. Wilkinson ◽

P. W. Trimby ◽

...

Keyword(s):

Thin Films ◽

Electron Backscatter Diffraction ◽

Contrast Imaging ◽

Electron Channelling ◽

Electron Backscatter ◽

Backscatter Diffraction

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Electron Channelling Contrast Imaging (ECCI) of Dislocations in Bulk Specimens

MRS Proceedings ◽

10.1557/proc-209-289 ◽

1990 ◽

Vol 209 ◽

Cited By ~ 5

Author(s):

J.T. Czernuszka ◽

N.J. Long ◽

E.D. Boyes ◽

P. B. Hirsch

Keyword(s):

Image Processing ◽

Processing Conditions ◽

Contrast Imaging ◽

Scattered Electron ◽

Highly Efficient ◽

Electron Channelling

ABSTRACTDislocations have been imaged in bulk specimens of Si using a FEG SEM operating at 30keV and 100keV, without using an energy filter, but by image processing of the back scattered electron signal collected by a highly efficient detector. The dislocation contrast is greater at 30 keV than at 10OkeV. Ilowever, the depth to which useful information may be obtained is greater at 1O0keV (˜210nm) than at 3OkeV (˜95nm). The final depth to which dislocations can be imaged is strongly dependent on image processing conditions.

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