I12-JEEP: Joint Engineering, Environmental and Processing
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Diamond Proposal Number(s):
[34540]
Open Access
Abstract: Fibrous plaster (FP) is a fabric-reinforced composite (FRC) comprising plaster of Paris (POP) and woven jute fabric (‘hessian’), historically used in decorative ceilings across the UK since the late 19th century. Despite its architectural significance, FP remains under-researched, limiting the development of reliable structural assessment methods. Recent ceiling failures have been linked to the tensile failure of the supporting component known as the ‘wad’. Acoustic emission (AE) provides a non-destructive means of remotely sensing and locating such failures from the underside of ceilings, yet its potential for extracting detailed information on FP wad failure processes remains unexplored. This study comprises two parts. First, an AE-based failure classification model was developed using unsupervised spherical k-means clustering to distinguish matrix cracking and fabric–matrix debonding based on the RA-AF method. Second, the first in-situ direct tensile tests on FP wad-analogue specimens conducted under synchrotron X-ray imaging were conducted at the I12 beamline of Diamond Light Source (DLS), UK, integrating AE monitoring with digital image correlation (DIC) and synchrotron X-ray computed tomography (sCT). This multi-modal dataset enabled examination of the AE model and internal failure analysis through digital volume correlation (DVC), while complementary crack analysis and the Kabsch algorithm provided new insight into the failure mechanisms of FP wads and revealed the reinforcement-bridging role of the hessian during progressive fracture. By linking remote AE monitoring with multi-scale observations, this study advances understanding of FP failure processes, offering a pathway for assessing historic ceilings and informing the design of more resilient FP components.
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Jun 2026
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I12-JEEP: Joint Engineering, Environmental and Processing
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Diamond Proposal Number(s):
[36935]
Open Access
Abstract: Twinning-induced plasticity (TWIP) steels exhibit exceptional combinations of strength and ductility due to the activation of deformation twinning in the FCC austenite matrix. While the formation of deformation twins during monotonic deformation has been widely studied, the reversibility of twin-related defects during cyclic tensile loading and its influence on cyclic stability remain insufficiently understood. In this study, a high-Mn twinning-induced plasticity (TWIP) steel is investigated using in situ high-energy synchrotron X-ray diffraction during continuous cyclic tensile loading under two strain amplitudes over a wide temperature range (173–523 K). Time-resolved single-shot diffraction measurements enable quantitative tracking of stacking fault energy, twin fault probability, dislocation density and texture during deformation. The results reveal partially reversible evolution of faulted microstructures during cyclic tensile loading, indicating repeated activation of twinning and detwinning processes mediated by Shockley partial dislocations. Cyclic variations in stacking and twin fault probabilities demonstrate that twin boundary migration occurs dynamically during tensile cycling even in the absence of compressive load reversal. The degree of reversibility is strongly influenced by cyclic strain amplitude and temperature, which govern the relative contributions of dislocation slip, mechanical twinning, and limited FCC-to-HCP transformation. Enhanced twinning activity at lower temperature or higher cyclic strain leads to pronounced cyclic fluctuations in defect density and texture evolution. The present time-resolved diffraction approach provides new experimental insight into the micromechanical origins of cyclic stability in low stacking fault energy austenitic alloys and highlights the role of reversible twinning and detwinning processes in governing their deformation behaviour.
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Jun 2026
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I12-JEEP: Joint Engineering, Environmental and Processing
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Diamond Proposal Number(s):
[40628]
Abstract: The short-range structure of the glass compositions 45SiO₂–25SrO–28Na₂O–2P₂O₅, 45SiO₂–12.5SrO–12.5CaO–28Na₂O–2P₂O₅, and 45SiO₂–25CaO–28Na₂O–2P₂O₅ was investigated using high-energy X-ray diffraction (XRD) supported by Reverse Monte Carlo (RMC) modelling and classical Molecular Dynamics (MD) simulations. Both RMC and MD models show good agreement with the experimental X-ray and published neutron diffraction S(Q), with only minor differences in average bond lengths and coordination numbers reflecting the characteristics of each approach. Consistent Si–O and P–O environments are observed across all compositions, confirming a similar short-range network structure. The modifier cations display composition-dependent variations: Na⁺ maintains a nearly constant coordination of ∼5, whereas Ca²⁺ and Sr²⁺ show distinct trends, with Ca–O distances of 2.34–2.41 Å and coordination numbers of ∼5–6, and Sr–O distances of 2.60–2.70 Å with coordination numbers of ∼4.6–5.7. The most significant structural changes arise in the mixed-modifier glass, where the coexistence of Ca and Sr results in a cooperative modifier effect evidenced by simultaneous reductions in Ca–O and Sr–O coordination and increased network disruption. This combined high-energy XRD–RMC–MD approach provides new insight into subtle modifier–modifier interactions in multicomponent bioactive glasses.
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May 2026
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I12-JEEP: Joint Engineering, Environmental and Processing
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Diamond Proposal Number(s):
[31744]
Open Access
Abstract: The inhomogeneous strains associated with Lüders bands in FeCo-2V have been studied. Mechanical testing revealed distinct elastic, Lüders band propagation, and work-hardening regimes. Digital Image Correlation (DIC) strain maps confirmed localised deformation during band propagation, transitioning to homogeneous plasticity post-saturation. Electron Backscatter Diffraction Kernel Average Misorientation (EBSD-KAM) analysis showed elevated misorientation angles in deformed regions, correlating with increased dislocation density. Synchrotron X-ray diffraction (XRD) showed peak broadening during Lüders band propagation, attributed to dislocation-induced lattice distortions that were quantified through Williamson-Hall analysis. The results demonstrate that Lüders bands in FeCo-2V arise from dislocation accumulation, with uniform peak width regions in XRD maps correlated with band propagation, while post-plateau work-hardening increased average peak widths. These findings provide insights into strain localisation in FeCo-2V.
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Apr 2026
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I12-JEEP: Joint Engineering, Environmental and Processing
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Sam
Riley
,
Antonios
Vamvakeros
,
Gustavo
Quino
,
John
Morley
,
Mengzheng
Ouyang
,
Andrew
Shevchuk
,
Kehan
Huang
,
Pierre-Olivier
Autran
,
Stefan
Michalik
,
Genoveva
Burca
,
Billy
Wu
,
Nigel
Brandon
,
Chandramohan
George
Diamond Proposal Number(s):
[36699]
Open Access
Abstract: Understanding the strain tolerance of both standard and mechanically flexible battery electrodes is prerequisite for optimizing performance, safety, and longevity, particularly in heavy-duty applications, flexible electronics and wearables. Achieving this requires a deeper understanding of how mechanical strain drives electrode degradation. In this work, we directly compare the strain response of electrospun (flexible) and slurry-cast (conventional) electrodes. To simulate acute mechanical stress, electrodes underwent a controlled 180° folding, pressing, and unfolding protocol designed to induce measurable damage, we then employed a combination of characterization techniques, including synchrotron X-ray nano-computed tomography, X-ray diffraction mapping, electrochemical analysis, and in situ Tensiometer-scanning electron microscopy to assess both structural and electrochemical degradation modes and provide a standardised upper-bound for strain induced damage. Our results reveal that electrospun electrodes exhibit significantly greater resilience to deformation, attributed to their freestanding architecture and fibrous morphology. These findings underscore the importance of characterizing deformation mechanisms to guide the design of high-performance batteries.
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Jan 2026
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I12-JEEP: Joint Engineering, Environmental and Processing
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Da
Guo
,
Chengbo
Zhu
,
Harry E.
Chapman
,
Kai
Zhang
,
Wei
Li
,
Shishira
Bhagavath
,
Robert
Atwood
,
Stefan
Michalik
,
Dmitry G.
Eskin
,
Iakovos
Tzanakis
,
Chu Lun Alex
Leung
,
Peter D.
Lee
Diamond Proposal Number(s):
[34549]
Open Access
Abstract: Directed energy deposition (DED) additive manufacturing (AM) can fabricate, repair, and join near-net-shaped components for high-performance engineering applications, including biomedical, energy, and transport sectors. The broader adoption of DED remains constrained by the limited number of alloys available that can be reliably manufactured without imperfections, hence limiting mechanical properties. Here, we designed an Al-Ni-Ce-Mn-Fe AM alloy that can achieve an ultra-fine microstructure (<5 μm), uniform distribution of intermetallics, low residual stress (<32 MPa), and superior mechanical properties in as-built DED components. Compared to DED AlSi10Mg in the as-build state using the same conditions, the yield increased by 70%, and the ultimate tensile strength by 50%. DED-AM involves rapid cooling and complex thermal conditions, which largely influence the property of the final components. Post-characterization cannot capture the time resolved thermal behavior, hence offer limited mechanism-based guide for alloy design. In this study, we develop a novel multimodal characterization methodology for correlative in situ X-ray imaging, X-ray diffraction, and infrared imaging, enabling quantification of the in situ thermal-related behavior, including phase evolution, temperature distribution and stress accumulation during DED. We elucidated key mechanisms driving the structure refinement and stress development in this alloy. The insights gained into the interplay between alloy composition, thermal-related behavior, and performance under specific AM conditions informs next-generation material design tailored for AM technologies.
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Jan 2026
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I12-JEEP: Joint Engineering, Environmental and Processing
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Diamond Proposal Number(s):
[30411]
Open Access
Abstract: Superelastic metastable β-Ti alloys, which undergo a stress-induced β → α″ transformation, have attracted significant attention in the biomedical and aerospace sectors. However, difficulty in predicting and controlling their superelastic properties, which is often linked to the ω phase, has prevented industrial uptake. The ω phase exists in two distinct forms, athermal (ωath) and isothermal (ωiso), yet despite their differences the two are often conflated, leading to conflicting statements surrounding their influence. Using in situ synchrotron diffraction, the mechanical response of two initially identical samples of Ti-24Nb (at.%), one cooled to form ωath and the other aged to form ωiso, was evaluated. The ωath sample exhibited superelasticity, with the ωath consumed by the growing α″ martensite. In contrast, the ωiso sample showed no evidence of a transformation. These data conclusively show that the ωath should not be considered a problem for superelastic alloy development, whilst the evolution of ωiso is highly detrimental.
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Dec 2025
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I12-JEEP: Joint Engineering, Environmental and Processing
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Diamond Proposal Number(s):
[31744]
Open Access
Abstract: FeCo-2V soft magnetic alloys offer attractive properties for demanding electromagnetic applications. While their magnetic properties are well-characterised under static loading conditions, the evolution of these properties under cyclic mechanical loading, as seen in service, remains insufficiently explored. This study examines how fatigue deformation alters the magnetic behaviour of an FeCo-2V alloy. The investigation employed strain-controlled cyclic loading combined with Single Sheet Tester measurements across multiple frequencies. A modified Bertotti loss separation analysis quantified the contributions of hysteresis and eddy current losses to total core loss. Experimental results demonstrated an increase in coercivity, and significant core loss increase during early-stage fatigue, followed by more gradual changes at higher cycle counts. The abrupt initial property changes correlate with rapid dislocation accumulation, while subsequent stabilisation reflects saturated defect densities. Notably, hysteresis losses dominated the degradation, while eddy current losses remained stable throughout cycling. These findings establish clear relationships between cyclic loading and magnetic properties in FeCo-2V and may serve as the basis for non-destructive fatigue assessment through magnetic measurements.
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Dec 2025
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I12-JEEP: Joint Engineering, Environmental and Processing
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Diamond Proposal Number(s):
[14657]
Open Access
Abstract: Learning to control reaction kinetics is essential for translating any chemical technology into real-world application. Based on time-resolved in situ powder X-ray diffraction data, we demonstrate the opportunity to tune mechanochemical reaction rates through the pre-activation of the starting reagents. For three model co-crystal systems, the pre-activation of the most stable reagent yields up to a ca 10-fold increase in the reaction rate, whilst negligible kinetic enhancement is seen when the less stable reagent is pre-activated. Moreover, we demonstrate how the polymorphic outcome of mechano-co-crystallization is also sensitive to pre-activation of the starting material. Our results suggest that reproducibility of mechanochemical processes requires detailed understanding over the origin and history of reagent powders, whilst providing a new conceptual framework to design and control mechanochemical reactions.
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Nov 2025
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I12-JEEP: Joint Engineering, Environmental and Processing
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Emily C.
Giles
,
Abbey
Jarvis
,
Pierrot S.
Attidekou
,
Kieran
O'Regan
,
Rosie
Madge
,
Alexander T.
Sargent
,
Beatrice
Browning
,
Anton
Zorin
,
Roberto
Sommerville
,
Alex J.
Green
,
Stefan
Michalik
,
Philip A.
Chater
,
Daniel
Reed
,
Emma
Kendrick
,
Laura L.
Driscoll
,
Peter
Slater
,
Phoebe K.
Allan
,
Paul
Anderson
,
Luke
Sweeney
Open Access
Abstract: Understanding the degradation of large format lithium-ion pouch cells – critical for electric vehicle applications – is vital to extend their lifetime and allow potential second-life application. Here, the impact on capacity fade and material degradation in two end-of-life cells, which were additionally subjected to accelerated aging to mimic extended use in second-life applications, were examined using powder synchrotron X-ray diffraction, Raman spectroscopy and electrochemical impedance spectroscopy, complemented by detailed post mortem analyses. The dominant mechanism of capacity loss under these conditions was found to be lithium inventory depletion, driven by processes such as electrolyte decomposition, lithium plating and solid electrolyte interphase growth. Structural changes in the graphite anode, including amorphization and reduced active material, were more pronounced under severe overcharging conditions. The blended cathode showed lithium inventory loss in both phases, but 92–94% capacity recovery was observed on subsequent cycling in half cells vs Li, illustrating its robustness, with little structural degradation observed. The finding that electrolyte degradation/loss in these cells was a more critical contributor to cell degradation toward the knee-point than electrode active material degradation/loss indicates that increasing – or replenishing – the electrolyte content could be a strategy to extend the usable life of such cells.
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Nov 2025
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