High quality transmission Kikuchi diffraction analysis of deformed alloys - Case study

Journal Article · Tue Nov 15 04:00:00 EST 2016 · Materials Characterization

DOI:https://doi.org/10.1016/J.MATCHAR.2016.10.013· OSTI ID:22689659

Tokarski, Tomasz ^[1]; Cios, Grzegorz ^[1]; Kula, Anna ^[2]; Bała, Piotr ^[1]

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1. AGH – University of Science and Technology, Academic Centre for Materials and Nanotechnology, al. Mickiewicza 30, 30-059 Krakow (Poland)
2. AGH – University of Science and Technology, Faculty of Non-Ferrous Metals, al. Mickiewicza 30, 30-059 Krakow (Poland)

Modern scanning electron microscopes (SEM) equipped with thermally assisted field emission guns (Schottky FEG) are capable of imaging with a resolution in the range of several nanometers or better. Simultaneously, the high electron beam current can be used, which enables fast chemical and crystallographic analysis with a higher resolution than is normally offered by SEM with a tungsten cathode. The current resolution that limits the EDS and EBSD analysis is related to materials' physics, particularly to the electron-specimen interaction volume. The application of thin, electron-transparent specimens, instead of bulk samples, improves the resolution and allows for the detailed analysis of very fine microstructural features. Beside the typical imaging mode, it is possible to use a standard EBSD camera in such a configuration that only transmitted and scattered electrons are detected. This modern approach was successfully applied to various materials giving rise to significant resolution improvement, especially for the light element magnesium based alloys. This paper presents an insight into the application of the transmission Kikuchi diffraction (TKD) technique applied to the most troublesome, heavily-deformed materials. In particular, the values of the highest possible acquisition rates for high resolution and high quality mapping were estimated within typical imaging conditions of stainless steel and magnesium-yttrium alloy. - Highlights: •Monte Carlo simulations were used to simulate EBSD camera intensity for various measuring conditions. •Transmission Kikuchi diffraction parameters were evaluated for highly deformed, light and heavy elements based alloys. •High quality maps with 20 nm spatial resolution were acquired for Mg and Fe based alloys. •High speed TKD measurements were performed at acquisition rates comparable to the reflection EBSD.

• OSTI ID: 22689659
• Journal Information: Materials Characterization, Journal Name: Materials Characterization Vol. 121; ISSN 1044-5803; ISSN MACHEX
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BACKSCATTERING
BEAM CURRENTS
COMPARATIVE EVALUATIONS
COMPUTERIZED SIMULATION
CRYSTALLOGRAPHY
ELECTRON BEAMS
ELECTRON DIFFRACTION
FIELD EMISSION
MAGNESIUM BASE ALLOYS
MICROSTRUCTURE
MONTE CARLO METHOD
REFLECTION
SCANNING ELECTRON MICROSCOPY
SPATIAL RESOLUTION
STAINLESS STEELS
TUNGSTEN
VELOCITY
YTTRIUM ALLOYS