6th International Congress on 3D Materials Science (3DMS 2022): Emergent Characterization Techniques I: Diffraction
Program Organizers: Dorte Juul Jensen, Technical University of Denmark; Marie Charpagne, University of Illinois; Keith Knipling, Naval Research Laboratory; Klaus-Dieter Liss, University of Wollongong; Matthew Miller, Cornell University; David Rowenhorst, Naval Research Laboratory
Tuesday 1:20 PM
June 28, 2022
Room: Columbia A&B
Location: Hyatt Regency Washington on Capitol Hill
Session Chair: Darren Pagan, Pennsylvania State University
1:20 PM Invited
Dictionary and Spherical Indexing of EBSD Data Sets: Marc De Graef1; 1Carnegie Mellon University
In 3D serial sectioning experiments, EBSD is a preferred acquisition mode because grain or phase segmentation becomes relatively simple. At the same time, EBSD is usually the rate limiting step when a large field of view is desired. Thus, indexing approaches that can work in real-time and keep up with recent advances in electron detector systems will have a significant impact on the overall acquisition time for a 3D experiment. In this contribution, we will review two whole-pattern indexing approaches: dictionary indexing (DI) and spherical indexing (SI) and compare them to each other and traditional Hough-based indexing (HI) in terms of execution speed and angular accuracy. We will highlight examples of DI and SI applications to serial sectioning data sets and discuss under which circumstances each approach produces the best results. We will conclude with an overview of available open source tools for EBSD data analysis.
1:50 PM
Looking Deeper: A Realization of 3DXRD Microscopy with Enhanced Spatial Resolution: Mustafacan Kutsal1; Grethe Winther1; Carsten Detlefs2; Henning Friis Poulsen1; 1Technical University of Denmark; 2European Synchrotron Radiation Facility
In this study, we present a validation of a new modality of three dimensional x-ray diffraction (3DXRD) microscopy that can provide 3D maps with spatial resolution better than ~2 μm. The experimental parameters affecting the quality of the maps are optimized via a series of simulations with FABLE package’s PolyXSim software. In these simulations, 3D maps of a physically relevant phantom microstructure are simulated on a large field-of-view detector (15,000 x 15,000 pixels). The experimental requirements for obtaining certain number of grains with enhanced resolution are explored with respect to signal-to-noise ratio, pixel size of the detector and reciprocal space sampling. With the presented optimization, 3D maps of 1000 grains with average size of 1 μm can be obtained with an accuracy of ~0.3 μm in center-of-mass position with ~0.0045° in orientation. Depending on the progress, first experimental results will also be presented.
2:10 PM
Helical Phyllotaxis and Conventional Laboratory Diffraction Contrast Tomography (LabDCT) Acquisition Strategies for Characterization of 3D Grain Orientations: Eshan Ganju1; Eugenia Nieto2; Javier Llorca2; Nikhilesh Chawla1; 1Purdue University; 2IMDEA Materials Institute
The acquisition of high-fidelity 3D grain maps is essential to advance our understanding of the micromechanical behavior of crystalline materials. The past few years have seen considerable advances in the acquisition of accurate grain maps using Laboratory Diffraction Contrast Tomography (LabDCT) with recent developments in advanced acquisition strategies, such as helical phyllotaxis scans (HP-LabDCT). In conventional LabDCT, a sample with a challenging geometry – such as a vertically extended sample – is scanned layer-by-layer; however, in an HP-LabDCT, the same sample is scanned by moving it in a helical motion, allowing the entire sample to be scanned and reconstructed in a single process. In this study, we compared grain maps obtained using both conventional and helical phyllotaxis LabDCT scans to those obtained from Electron Backscatter Diffraction. We will present data on reliability of the grain orientations in Titanium obtained by the two acquisition strategies and discuss corresponding advantages and disadvantages.
2:30 PM
Correlative Microscopy: 3D EBSD with fs-Laser Plasma FIB-SEM: Bartlomiej Winiarski1; Remco Geurts1; 1Thermo Fisher Scientific
Multi-scale and multi-modal correlative microscopy methods, which involve the coordinated characterization of materials across a range of length scales using various apparatus, allowing solving a broad range of scientific problems previously unreachable by the typical experimental operando. The advent of FIB-SEM allowed for automated serial sectioning tomography, 3D-EDS and 3D-EBSD of material volumes ≤ 40 × 40 × 40 µm3. Plasma FIB-SEM (PFIB-SEM) expanded these techniques to volume ~ 250 × 250 × 250 µm3 keeping the voxels sizes in the dozens of nm-ranges. Recently, femtosecond Laser PFIB-SEM pushed these 3D techniques further to mm-scale volumes, setting the standards for multi-modal data collection from nm to mm scales.In this work we address current developments in 3D EBSD with Laser PFIB-SEM and in the framework of correlative microscopy. We discuss the effects of ultra-short pulse laser ablation on the EBSD results and we present various practical examples.
2:50 PM
First Use of a Coded Aperture for Depth Resolved Scattering of a Pink Beam.: Jon Tischler1; Doga Gursoy1; Dina Sheyfer1; Wenjun Liu1; Michael Wojcik1; 1Argonne National Laboratory
We fabricated a coded aperture consisting of 7.5µm wide by 7.5µm thick gold bars deposited on a SiN membrane in a de Bruijn sequence. The de Bruijn sequence was 256 bits long and EVERY 8-bit sub-sequence is unique, thus by scanning the aperture perpendicular to the bars across the diffracted rays, only 120µm of motion was needed to uniquely identify where every ray intersected the aperture. This device was tested at the Advanced Photon Source beam line 34-ID-E and using an algorithm that we have developed we depth resolved the pink beam scattering from a polycrystalline Ni foil having a grain size of ~30 µm. We successfully reconstructed depth resolved scattering images from areas that were single crystal as well as a deformed region displaying diffraction peaks smeared over multiple degrees. We will show fully processed internal grain maps and compare them to measurements collected using the older wire-scan method.
3:10 PM Break
3:40 PM
Laboratory X-ray Diffraction Contrast Tomography-improved Grain Mapping by Reconstruction with Magnified Diffraction Spots: Haixing Fang1; Adam Lindkvist1; Dorte Juul Jensen1; Yubin Zhang1; 1Technical University of Denmark
Although laboratory X-ray diffraction contrast tomography (LabDCT) is a very powerful technique for probing grain sizes, shapes and orientations in bulk samples, the method is currently limited to detecting relatively large grains (>20 μm) and the reconstruction of grain shapes is sometimes also unsatisfactory, especially for small grains. In the present work, we have investigated the possibility of improving grain reconstructions by moving the detector further away from the Laue focusing condition to obtain a geometrical magnification of diffraction spots. The magnification of diffraction spots is found to be an efficient way to improve both the detection limit and the accuracy in shape reconstruction. This is verified by comparisons between virtually rendered and reconstructed grain structures using a forward simulation approach. The improvements of spot magnification are also illustrated by mapping grains in a pure iron sample. Finally, the potential of using Machine Learning algorithms for detecting spots is discussed.
4:00 PM
Achieving Large Volume Grain Statistics with Laboratory Based Diffraction Contrast Tomography: Hrishi Bale1; Jun Sun2; Jette Oddershede2; Erik Lauridsen2; 1Carl Zeiss Microscopy Inc.; 2Xnovo Technology ApS
An integrated microstructural modeling approach, and ensuring the handshake between modeling and experimentation, relies on adequate experimental statistics. Furthermore, the simultaneous improvements in computing power and characterization techniques have opened up new possibilities in 4D analysis, beyond established 2D microstructural methods. Here we present the x-ray based technique of diffraction contrast tomography performed on a laboratory X-ray microscope. LabDCT is attractive in its ability to non-destructively produce detailed 3D grain maps(morphology and orientation) over large volumes of material up to 8 mm3 and beyond(when stitching multiple volumes), containing hundreds of grains, in a matter of hours. Such experimental data is essential for improving and validating simulation volumes. Additionally, due to its non-destructive operation, LabDCT enables tracking the evolution of structure through processes such as annealing or grain-growth, again providing a complement to analogous models. The technique and examples will be presented highlighting the use of large volume, large grain statistics.
4:20 PM
A High-fidelity Analytical Model for Multi-peak Bragg Coherent Diffraction Imaging of Compact Crystalline Domains: Siddharth Maddali1; Stephan Hruszkewycz1; 1Argonne National Laboratory
Fourth-generation synchrotrons now present the opportunity to track and study individual grains using Bragg coherent diffraction imaging (BCDI), image the crystallographic context and grain neighbor influences, by unifying BCDI with high-energy diffraction microscopy (HEDM) and diffraction contrast microscopy (DCT). Here I present a long-envisioned BCDI capability enabled by this unification: spatially resolved strain tensor reconstruction in individual grains by coupling independent BCDI datasets. I present an analytical diffraction model for BCDI reconstruction of lattice deformation, specially tailored to structural kinks with complex topologies (defects, dislocations). These are difficult to reconstruct with traditional phase retrieval. I will demonstrate the modeling of these features in the coherent diffraction imaging process using Fourier transform methods, which protects them from undesirable point-spread effects, preserving fidelity to the original structure in digital reconstructions. I will demonstrate how the spatial resolution of the reconstruction greatly benefits from coupling individual BCDI datasets within the forward model itself.
4:40 PM
The Development of a Laboratory-scale High-energy Diffraction Microscopy Instrument: Ashley Bucsek1; Robert Drake2; Kenneth Geauvreau2; Anasuya Adibhatla3; 1University of Michigan; 2Proto Manufacturing; 3Excillum
The synchrotron-based 3D X-ray diffraction (3DXRD) technique known as high-energy diffraction microscopy (HEDM) can be used to nondestructively measure 3D microscale information including the elastic strain tensor, crystallographic orientation, location, and volume of each grain for many hundreds to thousands of grains. For this reason, HEDM is arguably one of the most powerful experimental tools we have for mapping the interplay between micro- and macroscale material behavior. Currently, HEDM is only available at select synchrotrons around the world. Here, we present a laboratory-scale HEDM instrument that utilizes an indium liquid-metal jet X-ray source to produce a monochromatic 24 keV parallel box beam suitable for near-field and far-field HEDM measurements on bulk (~1 mm) single crystal, polycrystalline, or granular materials, particularly those composed of light elements (e.g., Al, Mg, Li). We discuss the design and construction of this instrument and present preliminary results.
5:00 PM
Liquid MetalJet X-ray Sources for High Resolution Characterization: Anasuya Adibhatla1; 1Excillum Inc
Replacing the solid anode by the high-speed jet of liquid metal has demonstrated its high power, and higher brilliance that is ten times above the current sources. Key applications include X-ray diffraction and scattering, but recently several publications have also shown very impressive X-ray imaging results using the liquid-metal-jet anode technology, especially in phase-contrast imaging. Based on advanced electron optics that were developed to exploit the higher power-loading capability of the liquid-metal-jet anode, a new nanofocus x-ray tube, with tungsten-coated diamond-transmission target, has been developed and commissioned. The nanofocus tube has reached an extreme resolution of 150 nm line-spacing resolution. With a capability to be operated in dual port setup, researchers can use characterization methods like non-destructive imaging, X-ray diffraction and high-resolution X-ray scattering in their lab with this liquid MetalJet X-ray source. Additional data will also be presented on use of this source in High-energy XPS.
5:20 PM
Examination of Dual Energy CT for Industrial X-ray: Odani Kazunori1; 1Shimadzu Corporation
One of the common problems about industrial X-ray CT is metal artifacts. As this countermeasure, in the industrial X-ray CT, a thin metal plate is placed between a sample and a X-ray generator to reduce beam hardening which is one of the contributing factors for metal artifacts. On the other hand, medical X-ray CT utilizes a technique termed Dual Energy CT. In Dual Energy CT, CT imaging is performed with different tube voltages as the mass attenuation coefficient of a sample varies depending on the X-ray energy. Dual Energy CT is more effective in reducing beam hardening than the aforementioned thin metal plate method commonly used in industrial X-ray CT. However, it is not widely used in industrial X-ray CT. In order to verify the effect of Dual Energy on CT data, basic experiments were conducted using the inspeXio SMX-225CT FPD HR Plus (Shimadzu Corp.).