David Dingley - Academia.edu (original) (raw)

Papers by David Dingley

Research paper thumbnail of Method and apparatus for determining crystallographic characteristics in response to confidence factors

[57] ABSTRACT An apparatus for determining the reliability of crystallographic solutions of a spe... more [57] ABSTRACT An apparatus for determining the reliability of crystallographic solutions of a specimen includes an electron beam generator, a stage for holding the specimen, an image collection system for obtaining diffraction images of crystals within the specimen, and processor for processing the diffraction images to obtain most probable indexing solutions for the crystals and to generate confidence factors associated with the most probable indexing solutions. The apparatus may utilize the confidence factors to determine the ...

Research paper thumbnail of Orientation Contrast Imaging of Microstructures in Rocks Using Forescatter Detectors in the Scanning Electron Microscope

Mineralogical Magazine, 1996

We have developed a system using 'forescatter detectors' for backscattered imaging of specimen su... more We have developed a system using 'forescatter detectors' for backscattered imaging of specimen surfaces inclined at 50-80 ~ to the incident beam (inclined-scanning) in the SEM. These detectors comprise semiconductor chips placed below the tilted specimen. Forescatter detectors provide an orientation contrast (OC) image to complement quantitative crystallographic data from electron backscatter patterns (EBSP). Specimens were imaged using two detector geometries and these images were compared to those collected with the specimen surface normal to the incident beam (normal-scanning) using conventional backscattered electron detector geometries and also to an automated technique, orientation imaging microscopy (DIM). When normal-scanning, the component of the BSE signal relating to the mean atomic number (z) of the material is an order of magnitude greater than any OC component, making OC imaging in polyphase specimens almost impossible. Images formed in inclined-scanning, using forescatter detectors, have OC and z-contrast signals of similar magnitude, allowing OC imaging in polyphase specimens.

Research paper thumbnail of CONFERENCE REPORT: Scanning electron microscopy systems and applications

Physics in Technology, 1974

Research paper thumbnail of Texture Observed in Iron Films Evaporated on {111}Copper Buffer Layer

Research paper thumbnail of Thin Films of Iron and Vanadium Evaporated on Copper Film

Research paper thumbnail of The Mechanical Properties of the Matrix in Continuous Silicon Carbide Fibre Reinforced 6061 Aluminium

Composites Science and Technology, 1991

Research paper thumbnail of The Development of Automated Diffraction in Scanning and Transmission Electron Microscopy

Electron Backscatter Diffraction in Materials Science, 2000

Research paper thumbnail of Phase Identification Through Symmetry Determination in EBSD Patterns

Electron Backscatter Diffraction in Materials Science, 2009

Research paper thumbnail of Advanced Software Capabilities for Automated EBSD

Electron Backscatter Diffraction in Materials Science, 2000

Research paper thumbnail of Measurement of boundary plane inclination in a scanning electron microscope

Scripta Metallurgica, 1989

Research paper thumbnail of An Experimental Investigation of Grain Boundary Structure Effects on Grain Growth

Materials Science Forum, 1996

Abstract Orientation imaging microscopy has been used to investigate the effects of grain boundar... more Abstract Orientation imaging microscopy has been used to investigate the effects of grain boundary structure, as characterized by lattice misorientations, on grain growth. While other microstructural features are also of primary importance, analysis reveals that the crystallographic structure of grain boundaries also has a major affect on grain growth. These affects are both material and process dependent. The capabilities of OIM in investigating these materials is demonstrated by careful analysis of texture and microtexture as related ...

Research paper thumbnail of A simple straining stage for the scanning electron microscope

Research paper thumbnail of Scanning electron microscopy systems and applications

Physics in Technology, 1974

Research paper thumbnail of High-resolution elastic strain measurement from electron backscatter diffraction patterns: New levels of sensitivity

In this paper, we demonstrate that the shift between similar features in two electron backscatter... more In this paper, we demonstrate that the shift between similar features in two electron backscatter diffraction (EBSD) patterns can be measured using cross-correlation based methods to +/- 0.05 pixels. For a scintillator screen positioned to capture the usual large solid angle employed in EBSD orientation mapping this shift corresponds to only approximately 8.5 x 10(-5)rad at the pattern centre. For wide-angled EBSD patterns, the variation in the entire strain and rotation tensor can be determined from single patterns. Repeated measurements of small rotations applied to a single-crystal sample, determined using the shifts at four widely separated parts of the EBSD patterns, showed a standard deviation of 1.3 x 10(-4) averaged over components of the displacement gradient tensor. Variations in strains and rotations were measured across the interface in a cross-sectioned Si1-x Gex epilayer on a Si substrate. Expansion of the epilayer close to the section surface is accommodated by tensile strains and lattice curvature that extend a considerable distance into the substrate. Smaller and more localised shear strains are observed close to the substrate-layer interface. EBSD provides an impressive and unique combination of high strain sensitivity, high spatial resolution and ease of use.

Research paper thumbnail of Mapping of Strain Tensor Components in Polycrystalline Samples using EBSD

Research paper thumbnail of Dislocation Invisibility in Dark-Field Electron Microscopy

physica status solidi (b), 1970

... Fig. 4a, b, and c illustrate a case of anomalous invisibility in magnesium. The imaging refle... more ... Fig. 4a, b, and c illustrate a case of anomalous invisibility in magnesium. The imaging reflection is 1010. In Fig. 4a, taken at a positive deviation from the Bragg position, dislocations marked A were shown to have a g . b value of 3. They have become invisible in Fig. ...

Research paper thumbnail of Dynamic Background Correction of Electron Backscatter Diffraction Patterns

Microscopy and Microanalysis, 2005

Research paper thumbnail of Elastic Strain Tensor Mapping - Extending the Limits of EBSD Analysis

Microscopy and Microanalysis, 2005

Electron back scatter diffraction (EBSD) is a key quantitative microstructural analysis technique... more Electron back scatter diffraction (EBSD) is a key quantitative microstructural analysis technique in many commercial and academic materials research laboratories. The typical angular precision of orientation measurements made by commercial EBSD systems is of the order of 0.5, or 10-2 rad. With the elastic limit typically at a strain of~ 10-3 this precision needs to be improved by a least an order of magnitude if elastic strain effects are to be detectable.

Research paper thumbnail of High Accuracy EBSD - A Review of Recent Applications, Innovations, and Remaining Challenges

Microscopy and Microanalysis, 2011

Research paper thumbnail of Determination of Crystal Structure from Electron Backscatter Diffraction Patterns

Microscopy and Microanalysis, 2009

Research paper thumbnail of Method and apparatus for determining crystallographic characteristics in response to confidence factors

[57] ABSTRACT An apparatus for determining the reliability of crystallographic solutions of a spe... more [57] ABSTRACT An apparatus for determining the reliability of crystallographic solutions of a specimen includes an electron beam generator, a stage for holding the specimen, an image collection system for obtaining diffraction images of crystals within the specimen, and processor for processing the diffraction images to obtain most probable indexing solutions for the crystals and to generate confidence factors associated with the most probable indexing solutions. The apparatus may utilize the confidence factors to determine the ...

Research paper thumbnail of Orientation Contrast Imaging of Microstructures in Rocks Using Forescatter Detectors in the Scanning Electron Microscope

Mineralogical Magazine, 1996

We have developed a system using 'forescatter detectors' for backscattered imaging of specimen su... more We have developed a system using 'forescatter detectors' for backscattered imaging of specimen surfaces inclined at 50-80 ~ to the incident beam (inclined-scanning) in the SEM. These detectors comprise semiconductor chips placed below the tilted specimen. Forescatter detectors provide an orientation contrast (OC) image to complement quantitative crystallographic data from electron backscatter patterns (EBSP). Specimens were imaged using two detector geometries and these images were compared to those collected with the specimen surface normal to the incident beam (normal-scanning) using conventional backscattered electron detector geometries and also to an automated technique, orientation imaging microscopy (DIM). When normal-scanning, the component of the BSE signal relating to the mean atomic number (z) of the material is an order of magnitude greater than any OC component, making OC imaging in polyphase specimens almost impossible. Images formed in inclined-scanning, using forescatter detectors, have OC and z-contrast signals of similar magnitude, allowing OC imaging in polyphase specimens.

Research paper thumbnail of CONFERENCE REPORT: Scanning electron microscopy systems and applications

Physics in Technology, 1974

Research paper thumbnail of Texture Observed in Iron Films Evaporated on {111}Copper Buffer Layer

Research paper thumbnail of Thin Films of Iron and Vanadium Evaporated on Copper Film

Research paper thumbnail of The Mechanical Properties of the Matrix in Continuous Silicon Carbide Fibre Reinforced 6061 Aluminium

Composites Science and Technology, 1991

Research paper thumbnail of The Development of Automated Diffraction in Scanning and Transmission Electron Microscopy

Electron Backscatter Diffraction in Materials Science, 2000

Research paper thumbnail of Phase Identification Through Symmetry Determination in EBSD Patterns

Electron Backscatter Diffraction in Materials Science, 2009

Research paper thumbnail of Advanced Software Capabilities for Automated EBSD

Electron Backscatter Diffraction in Materials Science, 2000

Research paper thumbnail of Measurement of boundary plane inclination in a scanning electron microscope

Scripta Metallurgica, 1989

Research paper thumbnail of An Experimental Investigation of Grain Boundary Structure Effects on Grain Growth

Materials Science Forum, 1996

Abstract Orientation imaging microscopy has been used to investigate the effects of grain boundar... more Abstract Orientation imaging microscopy has been used to investigate the effects of grain boundary structure, as characterized by lattice misorientations, on grain growth. While other microstructural features are also of primary importance, analysis reveals that the crystallographic structure of grain boundaries also has a major affect on grain growth. These affects are both material and process dependent. The capabilities of OIM in investigating these materials is demonstrated by careful analysis of texture and microtexture as related ...

Research paper thumbnail of A simple straining stage for the scanning electron microscope

Research paper thumbnail of Scanning electron microscopy systems and applications

Physics in Technology, 1974

Research paper thumbnail of High-resolution elastic strain measurement from electron backscatter diffraction patterns: New levels of sensitivity

In this paper, we demonstrate that the shift between similar features in two electron backscatter... more In this paper, we demonstrate that the shift between similar features in two electron backscatter diffraction (EBSD) patterns can be measured using cross-correlation based methods to +/- 0.05 pixels. For a scintillator screen positioned to capture the usual large solid angle employed in EBSD orientation mapping this shift corresponds to only approximately 8.5 x 10(-5)rad at the pattern centre. For wide-angled EBSD patterns, the variation in the entire strain and rotation tensor can be determined from single patterns. Repeated measurements of small rotations applied to a single-crystal sample, determined using the shifts at four widely separated parts of the EBSD patterns, showed a standard deviation of 1.3 x 10(-4) averaged over components of the displacement gradient tensor. Variations in strains and rotations were measured across the interface in a cross-sectioned Si1-x Gex epilayer on a Si substrate. Expansion of the epilayer close to the section surface is accommodated by tensile strains and lattice curvature that extend a considerable distance into the substrate. Smaller and more localised shear strains are observed close to the substrate-layer interface. EBSD provides an impressive and unique combination of high strain sensitivity, high spatial resolution and ease of use.

Research paper thumbnail of Mapping of Strain Tensor Components in Polycrystalline Samples using EBSD

Research paper thumbnail of Dislocation Invisibility in Dark-Field Electron Microscopy

physica status solidi (b), 1970

... Fig. 4a, b, and c illustrate a case of anomalous invisibility in magnesium. The imaging refle... more ... Fig. 4a, b, and c illustrate a case of anomalous invisibility in magnesium. The imaging reflection is 1010. In Fig. 4a, taken at a positive deviation from the Bragg position, dislocations marked A were shown to have a g . b value of 3. They have become invisible in Fig. ...

Research paper thumbnail of Dynamic Background Correction of Electron Backscatter Diffraction Patterns

Microscopy and Microanalysis, 2005

Research paper thumbnail of Elastic Strain Tensor Mapping - Extending the Limits of EBSD Analysis

Microscopy and Microanalysis, 2005

Electron back scatter diffraction (EBSD) is a key quantitative microstructural analysis technique... more Electron back scatter diffraction (EBSD) is a key quantitative microstructural analysis technique in many commercial and academic materials research laboratories. The typical angular precision of orientation measurements made by commercial EBSD systems is of the order of 0.5, or 10-2 rad. With the elastic limit typically at a strain of~ 10-3 this precision needs to be improved by a least an order of magnitude if elastic strain effects are to be detectable.

Research paper thumbnail of High Accuracy EBSD - A Review of Recent Applications, Innovations, and Remaining Challenges

Microscopy and Microanalysis, 2011

Research paper thumbnail of Determination of Crystal Structure from Electron Backscatter Diffraction Patterns

Microscopy and Microanalysis, 2009