TY - JOUR
T1 - Correction of artefacts associated with large area EBSD
AU - Gholinia, Ali
AU - Winiarski, Bartlomiej
AU - Mingard, K
AU - Gee, M
AU - Withers, Philip
N1 - Funding Information:
This work was supported by the grant from the University of Manchester – EPSRC – NPL research program: 3D Assessment of Surface Integrity and Performance (EP/H020047/1). Authors acknowledge GATAN for lending the prototype Illion broad ion beam system. The facilities now lie within, and are maintained through, the Henry Royce Institute through EPSRC grants EP/R00661X/1 , EP/S019367/1 , EP/P025021/1 and EP/P025498/1 . PJW is grateful to the ERC for advanced grant funding through CORREL-CT Grant No. 695638.
Funding Information:
This work was supported by the grant from the University of Manchester – EPSRC – NPL research program: 3D Assessment of Surface Integrity and Performance (EP/H020047/1). Authors acknowledge GATAN for lending the prototype Illion broad ion beam system. The facilities now lie within, and are maintained through, the Henry Royce Institute through EPSRC grants EP/R00661X/1, EP/S019367/1, EP/P025021/1 and EP/P025498/1. PJW is grateful to the ERC for advanced grant funding through CORREL-CT Grant No. 695638.
Publisher Copyright:
© 2021
PY - 2021/5/14
Y1 - 2021/5/14
N2 - There is an increasing requirement for the acquisition of large two (2D) or three (3D) dimensional electron back scattered diffraction (EBSD) maps. It is a well-known, but largely neglected fact, that EBSD maps may contain distortions. These include long-range distortions, which can be caused by the interaction of the electron beam with the sample geometry and it can also arise from sample or beam drift. In addition there are shorter range artefacts arising from topographical features, such as curtaining. The geometrical distortions can be minimised by careful SEM calibrations and sample alignment. However, the long-range distortions become increasingly prevalent when acquiring large area 2D EBSD maps which take a long time to acquire and thus are especially prone to drift. These distortions are especially evident in serial section tomography (SST) when 2D maps are stacked on top of one another to produce 3D maps. Here we quantify these distortions for large area EBSD data by referencing them to secondary electron (SE) images for 3D-EBSD data acquired on a WC–Co hardmetal. Long-range distortions (due to drift) equating to around 10μm across a 200μm x 175 μm area map, and short-range distortions (due to topographical effects) as large as 3 μm over a distance of 40 µm were observed. Methods for correcting these distortions are then proposed. This study illustrates the benefits and necessity of such corrections if morphological features are to be properly interpreted when collecting large 3D EBSD datasets, for example by mechanical sectioning, serial block face SEM ultramicrotomy, laser sectioning, FIB-SEM tomography, PFIB spin milling, etc.
AB - There is an increasing requirement for the acquisition of large two (2D) or three (3D) dimensional electron back scattered diffraction (EBSD) maps. It is a well-known, but largely neglected fact, that EBSD maps may contain distortions. These include long-range distortions, which can be caused by the interaction of the electron beam with the sample geometry and it can also arise from sample or beam drift. In addition there are shorter range artefacts arising from topographical features, such as curtaining. The geometrical distortions can be minimised by careful SEM calibrations and sample alignment. However, the long-range distortions become increasingly prevalent when acquiring large area 2D EBSD maps which take a long time to acquire and thus are especially prone to drift. These distortions are especially evident in serial section tomography (SST) when 2D maps are stacked on top of one another to produce 3D maps. Here we quantify these distortions for large area EBSD data by referencing them to secondary electron (SE) images for 3D-EBSD data acquired on a WC–Co hardmetal. Long-range distortions (due to drift) equating to around 10μm across a 200μm x 175 μm area map, and short-range distortions (due to topographical effects) as large as 3 μm over a distance of 40 µm were observed. Methods for correcting these distortions are then proposed. This study illustrates the benefits and necessity of such corrections if morphological features are to be properly interpreted when collecting large 3D EBSD datasets, for example by mechanical sectioning, serial block face SEM ultramicrotomy, laser sectioning, FIB-SEM tomography, PFIB spin milling, etc.
KW - Broad ion beam polishing
KW - Cermet
KW - Computed tomography (CT)
KW - Serial block face sectioning electron microscopy (SBFSEM)
KW - electron back scatter diffraction
KW - focused ion beam (FIB)
U2 - 10.1016/j.ultramic.2021.113315
DO - 10.1016/j.ultramic.2021.113315
M3 - Article
SN - 0304-3991
VL - 226
JO - Ultramicroscopy
JF - Ultramicroscopy
M1 - 113315
ER -