3D Studies of Indentation by Combined X-Ray Tomography and Digital Volume Correlation

Hardness testing obtains material properties from small specimens via measurement of load-displacement response to an imposed indentation; it is a surface characterisation technique so, except in optically transparent materials, there is no direct observation of the assumed damage and deformation processes within the material. Three-dimensional digital image correlation (digital volume correlation) is applied to study deformation beneath indentations, mapping the relative displacements between high-resolution synchrotron X-ray computed tomographs (0.9 μm voxel size). Two classes of material are examined: ductile aluminium-silicon carbide composite (Al-SiC) and brittle alumina (Al2O3). The measured displacements for Hertzian indentation in Al-SiC are in good agreement with an elastic-plastic finite element simulation. In alumina, radial cracking is observed beneath a Vickers indentation and the crack opening displacements are measured, in situ under load, for the first time. Potential applications are discussed of this characterization technique, which does not require resolution of microstructural features.

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Mechanisms of root reinforcement in soils: an experimental methodology using four-dimensional X-ray computed tomography and digital volume correlation

Proceedings of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rspa.2019.0838 ◽

2020 ◽

Vol 476 (2237) ◽

pp. 20190838

Author(s):

D. J. Bull ◽

J. A. Smethurst ◽

I. Sinclair ◽

F. Pierron ◽

T. Roose ◽

...

Keyword(s):

Computed Tomography ◽

Three Dimensional ◽

Shear Loading ◽

Soil Reinforcement ◽

Experimental Methodology ◽

Digital Volume Correlation ◽

X Ray ◽

Reinforced Soils ◽

Multi Scale ◽

X Ray Computed

Vegetation on railway or highway slopes can improve slope stability through the generation of soil pore water suctions by plant transpiration and mechanical soil reinforcement by the roots. To incorporate the enhanced shearing resistance and stiffness of root-reinforced soils in stability calculations, it is necessary to understand and quantify its effectiveness. This requires integrated and sophisticated experimental and multi-scale modelling approaches to develop an understanding of the processes at different length scales, from individual root–soil interaction through to full soil-profile or slope scale. One of the challenges with multi-scale models is ensuring that they sufficiently closely represent real behaviour. This requires calibration against detailed high-quality and data-rich experiments. This study presents a novel experimental methodology, which combines in situ direct shear loading of a willow root-reinforced soil with X-ray computed tomography to capture the three-dimensional chronology of soil and root deformation within the shear zone. Digital volume correlation (DVC) analysis was applied to the computed tomography dataset to obtain full-field three-dimensional displacement and strain information. This paper demonstrates the feasibility and discusses the challenges associated with DVC experiments on root-reinforced soils.

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Three-dimensional image correlation from X-ray computed tomography of solid foam

Composites Part A Applied Science and Manufacturing ◽

10.1016/j.compositesa.2007.11.011 ◽

2008 ◽

Vol 39 (8) ◽

pp. 1253-1265 ◽

Cited By ~ 200

Author(s):

Stéphane Roux ◽

François Hild ◽

Philippe Viot ◽

Dominique Bernard

Keyword(s):

Computed Tomography ◽

Three Dimensional ◽

Image Correlation ◽

X Ray ◽

Dimensional Image ◽

X Ray Computed ◽

Solid Foam

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LED Chip Deformation Measurement During the Operation Using the X-Ray CT Digital Volume Correlation

Volume 2: Advanced Electronics and Photonics, Packaging Materials and Processing; Advanced Electronics and Photonics: Packaging, Interconnect and Reliability; Fundamentals of Thermal and Fluid Transport in Nano, Micro, and Mini Scales ◽

10.1115/ipack2015-48785 ◽

2015 ◽

Cited By ~ 2

Author(s):

Pradeep Lall ◽

Junchao Wei

Keyword(s):

Three Dimensional ◽

Ct Scanning ◽

Image Correlation ◽

Reference Image ◽

Digital Volume Correlation ◽

X Ray ◽

Function Computation ◽

Fixed Subset ◽

Three Dimensional Measurement ◽

Strain Components

A high-power LED can generate tremendous heat under the operation, which causes the LED chip undergo large deformation. LED Wire Bonds may undergo deformation because of the mismatch between the LED chip and substrate. Presently, measurements of deformation and strain in operational electronics are limited to measurement on a cut-plane using techniques including digital image correlation and moiré interferometry based techniques. There is need for tools and techniques that can help quantify the in-situ chip deformation and interconnects inside the LED. Digital Volume Correlation (DVC) has been used in conjunction with X-ray Micro-CT for three-dimensional measurement of deformation and strain in LEDs under operational stresses. The Digital Volume Correlation has been used to correlate the undeformed image with deformed images by computing correlation functions throughout each voxel. The deformed images have been generated by CT scanning over the object while the LED is operational. The correlation function computation starts at specific fixed subset window in the reference image, and searches every possible subset window in the deformed image to identify the deformation in the electronic structure. Once the displacement components have been derived, the strain components have been computed by calculating the gradients of the displacement field. In this paper, the full strain field, both in-plane and out-plane strain, will be presented, and the LED chip deformation shape will be analyzed.

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Three-dimensional Analysis of an In Situ Double-torsion Test by X-ray Computed Tomography and Digital Volume Correlation

Experimental Mechanics ◽

10.1007/s11340-013-9727-4 ◽

2013 ◽

Vol 53 (7) ◽

pp. 1265-1275 ◽

Cited By ~ 8

Author(s):

P. Leplay ◽

J. Réthoré ◽

S. Meille ◽

M.-C. Baietto ◽

J. Adrien ◽

...

Keyword(s):

Computed Tomography ◽

Dimensional Analysis ◽

Three Dimensional ◽

Torsion Test ◽

Digital Volume Correlation ◽

X Ray ◽

X Ray Computed ◽

Double Torsion

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Three-dimensional displacement mapping of diffused Pt thermal barrier coatings via synchrotron X-ray computed tomography and digital volume correlation

Scripta Materialia ◽

10.1016/j.scriptamat.2015.10.033 ◽

2016 ◽

Vol 115 ◽

pp. 100-103 ◽

Cited By ~ 9

Author(s):

D. Khoshkhou ◽

M. Mostafavi ◽

C. Reinhard ◽

M.P. Taylor ◽

D.S. Rickerby ◽

...

Keyword(s):

Computed Tomography ◽

Thermal Barrier Coatings ◽

Three Dimensional ◽

Digital Volume Correlation ◽

Thermal Barrier ◽

Barrier Coatings ◽

X Ray ◽

Displacement Mapping ◽

X Ray Computed

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Three‐dimensional X‐ray‐computed tomography of 3300‐ to 6000‐year‐old Citrullus seeds from Libya and Egypt compared to extant seeds throws doubts on species assignments

Plants People Planet ◽

10.1002/ppp3.10220 ◽

2021 ◽

Author(s):

Katherine A. Wolcott ◽

Guillaume Chomicki ◽

Yannick M. Staedler ◽

Krystyna Wasylikowa ◽

Mark Nesbitt ◽

...

Keyword(s):

Computed Tomography ◽

Three Dimensional ◽

X Ray ◽

X Ray Computed

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Cover Feature: Non‐Destructive Three‐Dimensional Imaging of Metal Organic Framework Mixed Matrix Membranes using Lab‐based X‐ray Computed Tomography (Chemistry ‐ Methods 5/2021)

Chemistry–Methods ◽

10.1002/cmtd.202100034 ◽

2021 ◽

Vol 1 (5) ◽

pp. 202-202

Author(s):

Anton Jansson ◽

Ignacio Luz ◽

Ching‐Chang Chung ◽

Mustapha Soukri

Keyword(s):

Computed Tomography ◽

Metal Organic Framework ◽

Three Dimensional ◽

Mixed Matrix Membranes ◽

Mixed Matrix ◽

Three Dimensional Imaging ◽

X Ray ◽

Metal Organic ◽

X Ray Computed ◽

Non Destructive

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Visualizing Fluid Flows With X-Rays

Volume 1: Symposia, Parts A and B ◽

10.1115/fedsm2007-37023 ◽

2007 ◽

Cited By ~ 4

Author(s):

Theodore J. Heindel ◽

Terrence C. Jensen ◽

Joseph N. Gray

Keyword(s):

Computed Tomography ◽

Flow Visualization ◽

Three Dimensional ◽

Fluid Flows ◽

X Rays ◽

Radiographic Images ◽

Optical Access ◽

X Ray ◽

X Ray Computed ◽

Density Map

There are several methods available to visualize fluid flows when one has optical access. However, when optical access is limited to near the boundaries or not available at all, alternative visualization methods are required. This paper will describe flow visualization using an X-ray system that is capable of digital X-ray radiography, digital X-ray stereography, and digital X-ray computed tomography (CT). The unique X-ray flow visualization facility will be briefly described, and then flow visualization of various systems will be shown. Radiographs provide a two-dimensional density map of a three dimensional process or object. Radiographic images of various multiphase flows will be presented. When two X-ray sources and detectors simultaneously acquire images of the same process or object from different orientations, stereographic imaging can be completed; this type of imaging will be demonstrated by trickling water through packed columns and by absorbing water in a porous medium. Finally, local time-averaged phase distributions can be determined from X-ray computed tomography (CT) imaging, and this will be shown by comparing CT images from two different gas-liquid sparged columns.

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