Deformation Twinning Behavior of Twinning-induced Plasticity Steels with Different Carbon Concentrations – Part 1: Atomic Force Microscopy and Electron Backscatter Diffraction Measurements

AbstractHydrous fluids play a vital role in the chemical and rheological evolution of ductile, quartz-bearing continental crust, where fluid percolation pathways are controlled by grain boundary domains. In this study, widths of grain boundary domains in seven quartzite samples metamorphosed under varying crustal conditions were investigated using Atomic Force Microscopy (AFM) which allows comparatively easy, high magnification imaging and precise width measurements. It is observed that dynamic recrystallization at higher metamorphic grades is much more efficient at reducing grain boundary widths than at lower temperature conditions. The concept of force-distance spectroscopy, applied to geological samples for the first time, allows qualitative estimation of variations in the strength of grain boundary domains. The strength of grain boundary domains is inferred to be higher in the high grade quartzites, which is supported by Kernel Average Misorientation (KAM) studies using Electron Backscatter Diffraction (EBSD). The results of the study show that quartzites deformed and metamorphosed at higher grades have narrower channels without pores and an abundance of periodically arranged bridges oriented at right angles to the length of the boundary. We conclude that grain boundary domains in quartz-rich rocks are more resistant to fluid percolation in the granulite rather than the greenschist facies.

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Characterization of Two-Dimensional Transition Metal Dichalcogenides in the Scanning Electron Microscope Using Energy Dispersive X-ray Spectrometry, Electron Backscatter Diffraction, and Atomic Force Microscopy

Applied Microscopy ◽

10.9729/am.2015.45.3.131 ◽

2015 ◽

Vol 45 (3) ◽

pp. 131-134 ◽

Cited By ~ 2

Author(s):

Christian Lang ◽

Matthew Hiscock ◽

Kim Larsen ◽

Jonathan Moffat ◽

Ravi Sundaram

Keyword(s):

Electron Backscatter Diffraction ◽

Transition Metal Dichalcogenides ◽

Two Dimensional ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

Electron Backscatter ◽

Metal Dichalcogenides ◽

Backscatter Diffraction

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Direct Visualization of Grain Boundaries in Quartzites using Atomic Force Microscopy: Application to Study of Fluid Percolation in Continental Crust

10.21203/rs.3.rs-208925/v1 ◽

2021 ◽

Author(s):

Ritabrata Dobe ◽

Anuja Das ◽

Rabibrata Mukherjee ◽

Saibal Gupta

Keyword(s):

Atomic Force Microscopy ◽

Grain Boundary ◽

Continental Crust ◽

Electron Backscatter Diffraction ◽

Vital Role ◽

Force Microscopy ◽

Atomic Force ◽

Width Measurements ◽

Lower Temperature ◽

Backscatter Diffraction

Abstract Hydrous fluids play a vital role in the chemical and rheological evolution of ductile, quartz-bearing continental crust, where fluid percolation pathways are controlled by grain boundary domains. In this study, widths of grain boundary domains in seven quartzite samples metamorphosed under varying crustal conditions were investigated using Atomic Force Microscopy (AFM) which allows comparatively easy, high magnification imaging and precise width measurements. It is observed that dynamic recrystallization at higher metamorphic grades is much more efficient at reducing grain boundary widths than at lower temperature conditions. The concept of force-distance spectroscopy, applied to geological samples for the first time, allows qualitative estimation of variations in the strength of grain boundary domains. The strength of grain boundary domains is inferred to be higher in the high grade quartzites, which is supported by Kernel Average Misorientation (KAM) studies using Electron Backscatter Diffraction (EBSD). The results of the study show that quartzites deformed and metamorphosed at higher grades have narrower channels without pores and an abundance of periodically arranged bridges oriented at right angles to the length of the boundary. We conclude that grain boundary domains in quartz-rich rocks are more resistant to fluid percolation in the granulite rather than the greenschist facies.

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Electron-Backscatter Diffraction of Photovoltaic Thin Films

MRS Proceedings ◽

10.1557/proc-1012-y12-04 ◽

2007 ◽

Vol 1012 ◽

Cited By ~ 4

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.

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Growth of 4H-SiC Single Crystals on 6H-SiC Seeds with an Open Backside by PVT Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.615-617.15 ◽

2009 ◽

Vol 615-617 ◽

pp. 15-18 ◽

Cited By ~ 7

Author(s):

Emil Tymicki ◽

Krzysztof Grasza ◽

Katarzyna Racka ◽

Marcin Raczkiewicz ◽

Tadeusz Łukasiewicz ◽

...

Keyword(s):

Single Crystals ◽

Electron Backscatter Diffraction ◽

Structural Defects ◽

X Ray Diffraction ◽

Force Microscopy ◽

Optical Scanning ◽

Atomic Force ◽

The Stability ◽

Backscatter Diffraction ◽

Source Materials

4H-SiC single crystals grown by the seeded physical vapour transport method have been investigated. These crystals were grown on 6H-SiC seeds. The influence of the seed temperature, form and granulation of SiC source materials on the stability and efficiency of the 4H polytype growth have been investigated. A new way of the seed mounting - with an open backside - has been used. Crystals obtained were free of structural defects in the form of hexagonal voids. The crystalline structure of SiC crystals was investigated by EBSD (Electron Backscatter Diffraction) and X-Ray diffraction methods. Moreover, defects in crystals and wafers cut from these crystals were examined by optical, scanning electron and atomic force microscopy combined with KOH etching.

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Coupling Automated Electron Backscatter Diffraction with Transmission Electron and Atomic Force Microscopies

Microscopy and Microanalysis ◽

10.1017/s1431927600037193 ◽

2000 ◽

Vol 6 (S2) ◽

pp. 940-941

Author(s):

A.J. Schwartz ◽

M. Kumar ◽

P.J. Bedrossian ◽

W.E. King

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Thermomechanical Processing ◽

Electron Backscatter Diffraction ◽

Grain Boundary Character Distribution ◽

Atomic Force ◽

Transmission Electron ◽

Electron Backscatter ◽

Network Engineering ◽

Backscatter Diffraction

Grain boundary network engineering is an emerging field that encompasses the concept that modifications to conventional thermomechanical processing can result in improved properties through the disruption of the random grain boundary network. Various researchers have reported a correlation between the grain boundary character distribution (defined as the fractions of “special” and “random” grain boundaries) and dramatic improvements in properties such as corrosion and stress corrosion cracking, creep, etc. While much early work in the field emphasized property improvements, the opportunity now exists to elucidate the underlying materials science of grain boundary network engineering. Recent investigations at LLNL have coupled automated electron backscatter diffraction (EBSD) with transmission electron microscopy (TEM)5 and atomic force microscopy (AFM) to elucidate these fundamental mechanisms.An example of the coupling of TEM and EBSD is given in Figures 1-3. The EBSD image in Figure 1 reveals “segmentation” of boundaries from special to random and random to special and low angle grain boundaries in some grains, but not others, resulting from the 15% compression of an Inconel 600 polycrystal.

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