Investigation of Microcrack Growth in [0/90]s Composite Laminates

2003 ◽  
Author(s):  
Melody A. Verges ◽  
Paul J. Schilling ◽  
Paul D. Herrington ◽  
Arun K. Tatiparthi
Keyword(s):  
Optical Microscopy ◽  
Composite Laminates ◽  
Damage Evolution ◽  
Applied Load ◽  
Three Dimensional ◽  
Three Dimensions ◽  
X Ray ◽  
Computed Microtomography ◽  
X Ray Computed ◽  
Microcrack Growth

Techniques such as optical microscopy and X-radiography have provided useful information regarding damage in composite laminates, particular in therms of microcracking behavior in individual plies. This focuses on the investigation of microcracking and damage evolution in loaded composite laminates via X-ray computed microtomography. The main advantage in the use of such a technique is that damage within the composite can be assessed in three-dimensions without destruction of the composite. In this work, IM7/977–2, IM7/5555, and IM7/5276-1 coupons were uniaxially tested in a tensile substage, Graphs that convey microcracking density information as a function of applied load were created for [0/90/90/0] laminates. The three dimensional geometry and connectivity of microcracks and other damage in these samples were investigated through microtomographic reconstruction.

scholarly journals Gold Exploration in Two and Three Dimensions: Improved and Correlative Insights from Microscopy and X-Ray Computed Tomography

Minerals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 476
Author(s):  
Joshua Chisambi ◽  
Bjorn von der Heyden ◽  
Muofhe Tshibalanganda ◽  
Stephan Le Roux
Keyword(s):  
Computed Tomography ◽  
Spatial Distribution ◽  
Gold Mineralization ◽  
Three Dimensional ◽  
Three Dimensions ◽  
Low Grade ◽  
X Ray ◽  
3D Space ◽  
X Ray Computed ◽  
2D And 3D

In this contribution, we highlight a correlative approach in which three-dimensional structural/positional data are combined with two dimensional chemical and mineralogical data to understand a complex orogenic gold mineralization system; we use the Kirk Range (southern Malawi) as a case study. Three dimensional structures and semi-quantitative mineral distributions were evaluated using X-ray Computed Tomography (XCT) and this was augmented with textural, mineralogical and chemical imaging using Scanning Electron Microscopy (SEM) and optical microscopy as well as fire assay. Our results detail the utility of the correlative approach both for quantifying gold concentrations in core samples (which is often nuggety and may thus be misrepresented by quarter- or half-core assays), and for understanding the spatial distribution of gold and associated structures and microstructures in 3D space. This approach overlays complementary datasets from 2D and 3D analytical protocols, thereby allowing a better and more comprehensive understanding on the distribution and structures controlling gold mineralization. Combining 3D XCT analyses with conventional 2D microscopies derive the full value out of a given exploration drilling program and it provides an excellent tool for understanding gold mineralization. Understanding the spatial distribution of gold and associated structures and microstructures in 3D space holds vast potential for exploration practitioners, especially if the correlative approach can be automated and if the resultant spatially-constrained microstructural information can be fed directly into commercially available geological modelling software. The extra layers of information provided by using correlative 2D and 3D microscopies offer an exciting new tool to enhance and optimize mineral exploration workflows, given that modern exploration efforts are targeting increasingly complex and low-grade ore deposits.

Dimensional Quantification of Embedded Voids or Objects in Three Dimensions Using X-Ray Tomography

2012 ◽  
Vol 18 (2) ◽  
pp. 390-398 ◽  
Author(s):  
Brian M. Patterson ◽  
Juan P. Escobedo-Diaz ◽  
Darcie Dennis-Koller ◽  
Ellen Cerreta
Keyword(s):  
Digital Imaging ◽  
Three Dimensional ◽  
Three Dimensions ◽  
Post Processing ◽  
X Ray ◽  
Individual Object ◽  
Starting Point ◽  
X Ray Computed ◽  
The Individual ◽  
Processing Steps

AbstractScientific digital imaging in three dimensions such as when using X-ray computed tomography offers a variety of ways to obtain, filter, and quantify data that can produce vastly different results. These opportunities, performed during image acquisition or during the data processing, can include filtering, cropping, and setting thresholds. Quantifying features in these images can be greatly affected by how the above operations are performed. For example, during binarization, setting the threshold too low or too high can change the number of objects as well as their measured diameter. Here, two facets of three-dimensional quantification are explored. The first will focus on investigating the question of how many voxels are needed within an object to have accurate geometric statistics that are due to the properties of the object and not an artifact of too few voxels. These statistics include but are not limited to percent of total volume, volume of the individual object, Feret shape, and surface area. Using simple cylinders as a starting point, various techniques for smoothing, filtering, and other processing steps can be investigated to aid in determining if they are appropriate for a specific desired statistic for a real dataset. The second area of investigation is the influence of post-processing, particularly segmentation, on measuring the damage statistics in high purity Cu. The most important parts of the pathways of processing are highlighted.

Energy-Microcrack Growth Measurments for Mortar Cylinders in Compression

1997 ◽  
Vol 503 ◽  
Author(s):  
E. N. Nagy ◽  
E. N. Landis
Keyword(s):  
Crack Growth ◽  
Three Dimensional ◽  
Three Dimensions ◽  
Internal Crack ◽  
Internal Damage ◽  
X Ray ◽  
Deformation Curves ◽  
Microcrack Growth ◽  
Work Of Fracture ◽  
Initial Results

ABSTRACTA high resolution three-dimensional scanning technique called x-ray microtomography was applied to measure internal damage and crack growth in small mortar cylinders loaded in compression. Tomographic scans were made at different load increments in the same specimen. Three-dimensional image analysis was used to measure internal crack growth during each load increment. Load-deformation curves were used to measure the work of the external load on the specimen. Non-recoverable work of load was related to measured crack growth to estimate work of fracture in three dimensions. Initial results indicate a roughly linear relationship between work of load and internal crack area.

scholarly journals Preparation, Scanning and Analysis of Duckweed Using X-Ray Computed Microtomography

2021 ◽  
Vol 11 ◽  
Author(s):  
Dylan H. Jones ◽  
Brian S. Atkinson ◽  
Alexander Ware ◽  
Craig J. Sturrock ◽  
Anthony Bishopp ◽  
...  
Keyword(s):  
Plant Material ◽  
Three Dimensional ◽  
In Planta ◽  
Plant Structure ◽  
X Ray ◽  
Computed Microtomography ◽  
Preserve Sample ◽  
X Ray Computed ◽  
3D Volume ◽  
And Function

Quantification of anatomical and compositional features underpins both fundamental and applied studies of plant structure and function. Relatively few non-invasive techniques are available for aquatic plants. Traditional methods such as sectioning are low-throughput and provide 2-dimensional information. X-ray Computed Microtomography (μCT) offers a non-destructive method of three dimensional (3D) imaging in planta, but has not been widely used for aquatic species, due to the difficulties in sample preparation and handling. We present a novel sample handling protocol for aquatic plant material developed for μCT imaging, using duckweed plants and turions as exemplars, and compare the method against existing approaches. This technique allows for previously unseen 3D volume analysis of gaseous filled spaces, cell material, and sub-cellular features. The described embedding method, utilizing petrolatum gel for sample mounting, was shown to preserve sample quality during scanning, and to display sufficiently different X-ray attenuation to the plant material to be easily differentiated by image analysis pipelines. We present this technique as an improved method for anatomical structural analysis that provides novel cellular and developmental information.

Endocranial morphology of the petalichthyid placoderm Ellopetalichthys scheii from the Middle Devonian of Arctic Canada, with remarks on the inner ear and neck joint morphology of placoderms

2021 ◽  
Vol 58 (1) ◽  
pp. 93-104
Author(s):  
Marco Castiello ◽  
Anna Jerve ◽  
Maria Grace Burton ◽  
Matt Friedman ◽  
Martin D. Brazeau
Keyword(s):  
Middle Devonian ◽  
Complex Shape ◽  
Comparative Anatomy ◽  
Three Dimensional ◽  
Sister Group ◽  
Sister Group Relationship ◽  
X Ray ◽  
Computed Microtomography ◽  
X Ray Computed ◽  
Joint Morphology

Petalichthyid and “acanthothoracid” placoderms have taken pivotal positions in the debate on placoderm — and, by extension, jawed vertebrate — relationships owing to perceived similarities with certain jawless vertebrates. Neurocranial characters are integral to current hypotheses of early gnathostome relationships. Here, we describe the three-dimensionally preserved neurocranial anatomy of the petalichthyid placoderm Ellopetalichthys scheii (Kiær, 1915), from the Middle Devonian (early Eifelian) of Ellesmere Island, Canada. Using X-ray computed microtomography, we generated three-dimensional reconstructions of the endocranial surfaces, orbital walls, and cranial endocavity. These reconstructions verify the absence of a crus commune of the skeletal labyrinth and the complex shape of the petalichthyid endolympathic duct. Details of the craniothoracic joint and occipital musculature fossae help resolve the problematic comparative anatomy of the occipital surface of petalichthyids. These new data highlight similarities with arthrodire placoderms, consistent with older hypotheses of a sister-group relationship between petalichthyids and that clade.

Microstructure and damage evolution of SiCf/PyC/SiC and SiCf/BN/SiC mini-composites: A synchrotron X-ray computed microtomography study

2019 ◽  
Vol 45 (9) ◽  
pp. 11395-11402 ◽  
Author(s):  
Haitang Yang ◽  
Zilong Lu ◽  
Bixiong Bie ◽  
Zeyu Fu ◽  
Jianling Yue ◽  
...  
Keyword(s):  
Damage Evolution ◽  
X Ray ◽  
Computed Microtomography ◽  
X Ray Computed

scholarly journals 3D investigation of steel fiber distribution in reinforced concrete by X-ray microtomography

2015 ◽  
Vol 8 (5) ◽  
pp. 707-720 ◽  
Author(s):  
A. C. MACHADO ◽  
M. A. SILVA ◽  
R. D. T. FILHO ◽  
M. S. PFEIL ◽  
I. LIMA ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Reinforced Concrete ◽  
Three Dimensional ◽  
Absorption Capacity ◽  
Steel Fibers ◽  
Three Dimensions ◽  
Morphological Properties ◽  
X Ray ◽  
Brittle Behavior ◽  
Computed Microtomography

ABSTRACTThe effects of the inclusion of steel fibers in concrete have been widely studied in order to investigate possible changes in mechanical properties, such as the increase in tensile strength, ductility, stiffness, toughness (energy absorption capacity), and durability. An immediate consequence of this addition is the mitigation of concrete's brittle behavior, so that the material meets new quality requirements. In this context, it is important to study the spatial distribution of the entire internal structure of these materials. Three-dimensional computed microtomography is a non-destructive inspection technique used to characterize the internal structures of various materials based on X-ray interaction with the inspected object. Topological and morphological properties can be obtained directly in three dimensions by means of mathematical reconstruction of the radiographs, which allows analyzing, for example, porosity and distribution of objects. In this context, the aim of this study is to investigate the spatial distribution of steel fibers, as well as of porosity in reinforced concrete samples. To this end, we used a microtomography system calibrated to operate at a voltage of 80 kV, electric current of 100 μA and a pixel size equal to 24 µm. The results showed low porosity and that the steel fibers were not uniformly distributed throughout the sample.

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