Dislocation structure of deformed olivine single crystals from conventional EBSD maps
Abstract Dislocations, linear defects in a crystalline lattice characterized by their slip systems, can provide a record of grain internal deformation. Comprehensive examination of this record has been limited by intrinsic limitations of the observational methods. Transmission electro...
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| Format: | Article |
| Language: | English |
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Springer Berlin Heidelberg
2021
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| Online Access: | https://hdl.handle.net/1721.1/136757 |
| _version_ | 1811077304196005888 |
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| author | Faul, Ulrich |
| author_facet | Faul, Ulrich |
| author_sort | Faul, Ulrich |
| collection | MIT |
| description | Abstract
Dislocations, linear defects in a crystalline lattice characterized by their slip systems, can provide a record of grain internal deformation. Comprehensive examination of this record has been limited by intrinsic limitations of the observational methods. Transmission electron microscopy reveals individual dislocations, but images only a few square
$$\upmu$$
μ
m of sample. Oxidative decoration requires involved sample preparation and has uncertainties in detection of all dislocations and their types. The possibility of mapping dislocation density and slip systems by conventional (Hough-transform based) EBSD is investigated here with naturally and experimentally deformed San Carlos olivine single crystals. Geometry and dislocation structures of crystals deformed in orientations designed to activate particular slip systems were previously analyzed by TEM and oxidative decoration. A curvature tensor is calculated from changes in orientation of the crystal lattice, which is inverted to calculate density of geometrically necessary dislocations with the Matlab Toolbox MTEX. Densities of individual dislocation types along with misorientation axes are compared to orientation change measured on the deformed crystals. After filtering (denoising), noise floor and calculated dislocation densities are comparable to those reported from high resolution EBSD mapping. For samples deformed in [110]c and [011]c orientations EBSD mapping confirms [100](010) and [001](010), respectively, as the dominant slip systems. EBSD mapping thus enables relatively efficient observation of dislocation structures associated with intracrystalline deformation, both distributed, and localized at sub-boundaries, over substantially larger areas than has previously been possible. This will enable mapping of dislocation structures in both naturally and experimentally deformed polycrystals, with potentially new insights into deformation processes in Earth’s upper mantle. |
| first_indexed | 2024-09-23T10:40:50Z |
| format | Article |
| id | mit-1721.1/136757 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T10:40:50Z |
| publishDate | 2021 |
| publisher | Springer Berlin Heidelberg |
| record_format | dspace |
| spelling | mit-1721.1/1367572021-11-01T14:36:56Z Dislocation structure of deformed olivine single crystals from conventional EBSD maps Faul, Ulrich Abstract Dislocations, linear defects in a crystalline lattice characterized by their slip systems, can provide a record of grain internal deformation. Comprehensive examination of this record has been limited by intrinsic limitations of the observational methods. Transmission electron microscopy reveals individual dislocations, but images only a few square $$\upmu$$ μ m of sample. Oxidative decoration requires involved sample preparation and has uncertainties in detection of all dislocations and their types. The possibility of mapping dislocation density and slip systems by conventional (Hough-transform based) EBSD is investigated here with naturally and experimentally deformed San Carlos olivine single crystals. Geometry and dislocation structures of crystals deformed in orientations designed to activate particular slip systems were previously analyzed by TEM and oxidative decoration. A curvature tensor is calculated from changes in orientation of the crystal lattice, which is inverted to calculate density of geometrically necessary dislocations with the Matlab Toolbox MTEX. Densities of individual dislocation types along with misorientation axes are compared to orientation change measured on the deformed crystals. After filtering (denoising), noise floor and calculated dislocation densities are comparable to those reported from high resolution EBSD mapping. For samples deformed in [110]c and [011]c orientations EBSD mapping confirms [100](010) and [001](010), respectively, as the dominant slip systems. EBSD mapping thus enables relatively efficient observation of dislocation structures associated with intracrystalline deformation, both distributed, and localized at sub-boundaries, over substantially larger areas than has previously been possible. This will enable mapping of dislocation structures in both naturally and experimentally deformed polycrystals, with potentially new insights into deformation processes in Earth’s upper mantle. 2021-10-29T18:57:13Z 2021-10-29T18:57:13Z 2021-09-06 2021-09-12T03:08:18Z Article http://purl.org/eprint/type/JournalArticle https://hdl.handle.net/1721.1/136757 Physics and Chemistry of Minerals. 2021 Sep 06;48(9):35 PUBLISHER_CC en https://doi.org/10.1007/s00269-021-01157-3 Creative Commons Attribution https://creativecommons.org/licenses/by/4.0/ The Author(s) application/pdf Springer Berlin Heidelberg Springer Berlin Heidelberg |
| spellingShingle | Faul, Ulrich Dislocation structure of deformed olivine single crystals from conventional EBSD maps |
| title | Dislocation structure of deformed olivine single crystals from conventional EBSD maps |
| title_full | Dislocation structure of deformed olivine single crystals from conventional EBSD maps |
| title_fullStr | Dislocation structure of deformed olivine single crystals from conventional EBSD maps |
| title_full_unstemmed | Dislocation structure of deformed olivine single crystals from conventional EBSD maps |
| title_short | Dislocation structure of deformed olivine single crystals from conventional EBSD maps |
| title_sort | dislocation structure of deformed olivine single crystals from conventional ebsd maps |
| url | https://hdl.handle.net/1721.1/136757 |
| work_keys_str_mv | AT faululrich dislocationstructureofdeformedolivinesinglecrystalsfromconventionalebsdmaps |