I13-2-Diamond Manchester Imaging
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G. R.
Parker
,
D. S.
Eastwood
,
M.
Storm
,
K.
Vitharana
,
E. M.
Heatwole
,
I.
Lopez-pulliam
,
R. M.
Broilo
,
P. M.
Dickson
,
A.
Martinez
,
Christoph
Rau
,
N. K.
Bourne
Diamond Proposal Number(s):
[15068, 16650, 18198]
Abstract: High-resolution synchrotron x-ray radiography with computed tomography is used to observe the evolution of porosity created by thermal exposure in two HMX-based polymer-bonded explosive compositions; LX-04 and BX-63. The measurements were made in situ, over an extended period of time, during which the samples were heated on a slow-rate thermal trajectory. The tests ended with thermal-runaway to ignition after which the samples were consumed by combustion. The primary means of damage appears to be from mechanical debonding of the HMX-binder interface with secondary contribution from chemical decomposition. Confinement and binder properties affect the amount of porosity and permeability that develops. Additionally, observations were made describing the emergence and structure of an internal ignition volume, the formation and transport of a pre-ignition melt layer, and how the early stages of combustion were affected by material morphology, mechanical confinement and melt. The contact angle between molten HMX and the fluoropolymer, Viton A, is also presented. For the first time we have time-resolved x-ray images of ignition in sufficient detail to verify the mechanism of cookoff in polymer-bonded explosive compositions.
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Apr 2021
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I13-1-Coherence
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Ana Katrina C.
Estandarte
,
Jiecheng
Diao
,
Alice
Llewellyn
,
Anmol
Jnawali
,
Thomas M. M.
Heenan
,
Sohrab R.
Daemi
,
Josh J.
Bailey
,
Silvia
Cipiccia
,
Darren
Batey
,
Xiaowen
Shi
,
Christoph
Rau
,
Dan J. L.
Brett
,
Rhodri
Jervis
,
Ian K.
Robinson
,
Paul
Shearing
Diamond Proposal Number(s):
[25852, 25440, 24129, 22373, 22309, 21652]
Abstract: Due to complex degradation mechanisms, disparities between the theoretical and practical capacities of lithium-ion battery cathode materials persist. Specifically, Ni-rich chemistries such as LiNi0.8Mn0.1Co0.1O2 (or NMC811) are one of the most promising choices for automotive applications; however, they continue to suffer severe degradation during operation that is poorly understood, thus challenging to mitigate. Here we use operando Bragg coherent diffraction imaging for 4D analysis of these mechanisms by inspecting the individual crystals within primary particles at various states of charge (SoC). Although some crystals were relatively homogeneous, we consistently observed non-uniform distributions of inter- and intracrystal strain at all measured SoC. Pristine structures may already possess heterogeneities capable of triggering crystal splitting and subsequently particle cracking. During low-voltage charging (2.7–3.5 V), crystal splitting may still occur even during minimal bulk deintercalation activity; and during discharging, rotational effects within parallel domains appear to be the precursor for the nucleation of screw dislocations at the crystal core. Ultimately, this discovery of the central role of crystal grain splitting in the charge/discharge dynamics may have ramifications across length scales that affect macroscopic performance loss during real-world battery operation.
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Dec 2020
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I13-1-Coherence
I18-Microfocus Spectroscopy
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Peter
Martin
,
Christopher P.
Jones
,
Stuart
Bartlett
,
Konstantin
Ignatyev
,
Dave
Megson-smith
,
Yukihiko
Sato
,
Silvia
Cipiccia
,
Darren J.
Batey
,
Christoph
Rau
,
Keisuke
Sueki
,
Tatsuya
Ishii
,
Junya
Igarashi
,
Kazuhiko
Ninomiya
,
Atsushi
Shinohara
,
Alison
Rust
,
Thomas B.
Scott
Diamond Proposal Number(s):
[24769, 19881]
Open Access
Abstract: The structural form and elemental distribution of material originating from different Fukushima Daiichi Nuclear Power Plant reactors (Units 1 and 3) is hereby examined to elucidate their contrasting release dynamics and the current in-reactor conditions to influence future decommissioning challenges. Complimentary computed X-ray absorption tomography and X-ray fluorescence data show that the two suites of Si-based material sourced from the different reactor Units have contrasting internal structure and compositional distribution. The known event and condition chronology correlate with the observed internal and external structures of the particulates examined, which suggest that Unit 1 ejecta material sustained a greater degree of melting than that likely derived from reactor Unit 3. In particular, we attribute the near-spherical shape of Unit 1 ejecta and their internal voids to there being sufficient time for surface tension to round these objects before the hot (and so relatively low viscosity) silicate melt cooled to form glass. In contrast, a more complex internal form associated with the sub-mm particulates invoked to originate from Unit 3 suggest a lower peak temperature, over a longer duration. Using volcanic analogues, we consider the structural form of this material and how it relates to its environmental particulate stability and the bulk removal of residual materials from the damaged reactors. We conclude that the brittle and angular Unit 3 particulate are more susceptible to further fragmentation and particulate generation hazard than the round, higher-strength, more homogenous Unit 1 material.
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Dec 2020
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I13-1-Coherence
I13-2-Diamond Manchester Imaging
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Zhiguo
Zhang
,
Jia Chuan
Khong
,
Billy
Koe
,
Shifeng
Luo
,
Shi
Huang
,
Ling
Qin
,
Silvia
Cipiccia
,
Darren
Batey
,
Andrew J.
Bodey
,
Christoph
Rau
,
Yu Lung
Chiu
,
Zhu
Zhang
,
Jean-christophe
Gebelin
,
Nick
Green
,
Jiawei
Mi
Diamond Proposal Number(s):
[9974, 13488, 22525]
Open Access
Abstract: Synchrotron X-ray microtomography and ptychography were used to characterize the 3D network structure, morphology and distribution of metal carbides in an as-cast IN713LC Ni superalloy. MC typed carbides were found to distribute mainly on the grain boundary between the matrix γ and γ' phase. The differences in solidification cooling rate had a minor influence on the volume fraction of the MC type carbides, but significantly affected the carbide size, distribution and network morphology. Depending on the local composition of the remaining liquid phase and geometric constraints, the carbides can form either spherical or strip or network morphologies. The research demonstrated clearly the advantage and technical potential of using the two complementary tomography techniques synergistically to characterize non-destructively complex multiple-phase structures in three dimensional space with a spatial resolution of ~30 nm.
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Oct 2020
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I13-2-Diamond Manchester Imaging
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J.
Wade-zhu
,
R.
Krishna
,
A. J.
Bodey
,
M.
Davies
,
N. K.
Bourne
,
C.
Rau
,
B.
Davies
,
A.
Tzelepi
,
A. N.
Jones
,
B. J.
Marsden
,
P. M.
Mummery
Diamond Proposal Number(s):
[16668]
Abstract: Herein, the first study is presented using 4D synchrotron X-ray microtomography to capture all stages of crack development in neutron irradiated and radiolytically oxidised nuclear graphite. Employing a novel loading setup, specimens of Gilsocarbon graphite, both unirradiated and irradiated at 301 °C to 19.7 × 1020 neutrons/cm2 (∼2.6 displacements/atom (dpa)), were loaded to generate a crack. All stages of the fracture process were then captured using synchrotron X-ray imaging. Reconstructed tomographic images and 3D segmented crack volumes have been used to observe and analyse the irradiation-induced evolution of the graphite microstructure as well as corresponding changes in the crack initiation, propagation, and arrest behaviour of graphite after neutron irradiation. Close examination of the applied stress-strain curves highlights the suppression of micro-crack-based damage accumulation in irradiated graphite. Moreover, as well as the crack-bridging and deflection mechanisms characteristic of unirradiated graphite, crack arrest in the irradiated graphite is shown to be significantly influenced by crack tip blunting. This change is associated with the growth of the open pore structure of graphite, specifically the enlargement and increased frequency of macro-pores, resulting from the simultaneous radiolytic oxidation of the graphite microstructure during neutron irradiation.
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Jul 2020
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I13-2-Diamond Manchester Imaging
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Diamond Proposal Number(s):
[19746, 24892]
Open Access
Abstract: The I13 transmission X-ray microscope at Diamond Light Source (DLS) has been designed to cover a broad range of energies and field of views. The beamline operates on an undulator source, and a multilayer monochromator can be used to work at a larger bandwidth to enable faster acquisitions. The experimental design includes large working distances for the optics to allow installing in situ sample environments. This paper presents the current state of the experimental system and shows some of the latest results.
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Apr 2020
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I13-1-Coherence
I13-2-Diamond Manchester Imaging
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Open Access
Abstract: The Diamond Beamline I13L is dedicated to micro- and nano- imaging, with two independently operating branchlines. The imaging branch preforms imaging in real space, with In-line phase contrast imaging and grating interferometry at micrometre resolution and full-field transmission microscopy up to 50nm spatial resolution. Highest spatial resolution is achieved on the coherence branchline, where diffraction imaging methods such as Ptychography and Bragg-CDI are performed. The article provides an update about the experimental capabilities at the beamline with an emphasis on the rapidly evolving ptychography capabilities. The latter has evolved to an user-friendly method with non-expert users able to explore their science without any specific a-priory knowledge.
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Oct 2019
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I13-1-Coherence
I13-2-Diamond Manchester Imaging
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Christoph
Rau
,
Malte
Storm
,
Shashidhara
Marathe
,
Andrew J.
Bodey
,
Marie-christine
Zdora
,
Silvia
Cipiccia
,
Darren
Batey
,
Xiaowen
Shi
,
Sven
Schroeder
,
Gunjan
Das
,
Melanie
Loveridge
,
Ralf
Ziesche
,
Brian
Connolly
Open Access
Abstract: The DIAMOND beamline I13L is dedicated to multi-scale and multi-modal imaging in real and reciprocal space. The beamline consists of two independently operating experimental stations, located at a distance of more than 200 m from the source. The Imaging Branch performs micro-tomography with in-line phase contrast in the 6-30 keV energy range. In addition, a grating interferometry setup and a full-field microscope for nano-tomography are currently implemented. Other techniques providing high-resolution three-dimensional information, in particular coherent X-ray diffraction, are hosted on the Coherence Branch. All imaging methods are tested to operate with large energy bandwidths and therefore shorter exposure times. To this end, two options are currently used: the so-called ‘pink-beam’ mode using a reflecting mirror and X-ray filters and monochromatic mode using a multilayer monochromator. The operation mode enables science for in-situ and operando studies across a wide range of scientific areas.
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Oct 2019
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I13-2-Diamond Manchester Imaging
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Diamond Proposal Number(s):
[21327]
Open Access
Abstract: X-ray Grating Talbot Interferometer (XGTI) is already routinely used for quantitative phase contrast imaging of soft tissue samples. XGTI can be realized using various measurement techniques, depending on the X-ray source used, the required spatial resolution and the speed of acquisition. The phase-stepping measurement technique, which is commonly used for XGTI data acquisition, needs multiple acquisitions for a single projection. For fast imaging the Moiré technique, a single-shot technique, is often preferred. However, it requires two gratings which increases the dose on the sample. We have therefore examined the Spatial Harmonic Imaging (SHI) technique which is low-dose and single-shot, using the I13-2 Diamond-Manchester Beamline at Diamond Light Source (DLS). The DLS I13-2 beamline is equipped with a Double Crystal Monochromator (DCM) and a Multi-Layer Monochromator (MLM) to deliver monochromatic beam, which work at the energy bandwidths (ΔE/E) of 10-4 and 10-2, respectively. However, the disadvantage of using these monochromators, especially for fast imaging, is loss of X-ray flux. It has already been shown that XGTI can work with an energy bandwidth (ΔE/E) of 10-1. Our aim is to develop a single phase grating interferometer with pink beam from an undulator source, with X-ray mirror optics and multiple absorption filters, to obtain maximum possible flux with sufficient coherence and monochromaticity. We demonstrate performance with optimized beamline parameters for a photon energy of 15 keV with some demonstrative image reconstructions.
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Oct 2019
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I13-1-Coherence
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Diamond Proposal Number(s):
[17460]
Abstract: In this Letter, we report on the creation of hard x-ray beams carrying orbital angular momentum of topological charge
−ℏ
−ℏ
and
−3ℏ
−3ℏ
at a photon energy of 8.2 keV via spiral phase plates made out of fused silica by ultrashort-pulsed laser ablation. The phase plates feature a smooth phase ramp with a 0.5 μm nominal step height and a surface roughness of 0.5 μm. The measured vortex beams show submicrometer-sized donut rings and agree well with numerical modeling. Fused silica phase plates are potentially suited to manipulate the electromagnetic field in highly intense x-ray beams at x-ray free-electron laser sources.
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Sep 2019
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