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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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Abstract: Understanding how irradiation degrades superconductivity in REBCO coated conductor is a pressing field of research for the development of compact fusion devices. Here, defect formation in GdBa2Cu3O coated conductor is studied using a high dose of 2 MeV He ion irradiation. While laboratory based X-ray diffraction and magnetometry measurements show that the crystal structure becomes less well ordered with the loss of superconductivity in the material, transmission electron microscopy reveals a complex landscape of structural defects within the as-manufactured tape which complicate the identification and characterisation of irradiation induced structural changes. To resolve this, three sets of polarisation dependent extended X-ray absorption fine structure (EXAFS) spectroscopy experiments were carried out to map the local structure of the Gd, Ba, and Cu atomic sites within the material, providing three independent probes for studying irradiation defects within the structurally anisotropic REBCO unit cell. Here the Ba and Cu environments were the more sensitive to the irradiation treatment, with only small changes to the Gd local structure observed. Both the Ba and Cu local structures retained much of the pristine structure in the a/b-plane following irradiation, with greater shifts evident in the c-axis aligned measurements. In the irradiated Cu K edge EXAFS analysis, a shifted peak in the c-axis aligned measurements is observed that is not compatible with the REBCO local structure. This is attributed to an O site irradiation defect motif consistent with a Frenkel defect.

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Abstract: The volumetric additive manufacturing (VAM) of multifunctional polymer composites presents transformative potential for industries seeking sustainable, efficient, and precise production of complex geometries. However, challenges persist in controlling material properties, scaling for multifunctionality, and achieving cost-effective, eco-friendly manufacturing. This review explores state-of-the-art advancements in VAM technologies, including magnetic field-assisted reshaping, which decouples geometric complexity from initial fabrication. By utilizing external fields to reconfigure simple 3D-printed geometries into intricate structures, this approach drastically reduces production times, energy consumption, and interlayer defects. The study highlights the urgent need for process-serving composite materials with self-tuning properties, capable of responding to electromagnetic fields for geometric reshaping, enhanced reinforcement distribution, and polymerization control. Applications across aerospace, biomedical, and automotive industries currently underscore the versatility and sustainability of these methods. Furthermore, this chapter advocates for integrating circular manufacturing principles, emphasizing reusability and recyclability, to extend the lifecycle of components and minimize environmental impact. Emerging techniques in field-assisted VAM offer profound opportunities for scaling up complex, multifunctional composite production, fostering a paradigm shift toward green and adaptive manufacturing practices.

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Abstract: Modern electroconductive materials involve copper-based carbon-enhanced composites featuring convenient mechanical properties and, simultaneously, favorable electric conductivity. Such composites can be processed by deformation/thermomechanical treatments to introduce advantageous microstructures, further enhancing their performance. The study features powder-based copper–carbon (Cu/C) composites, fabricated from chemical vapor deposition-prepared powder mixture by a direct consolidation using the rotary swaging method, which enables to eliminate the typical (costly and time consuming) preparation steps of consolidation and sintering. The directly consolidated Cu/C composites were further processed by the severe plastic deformation method of high-pressure torsion (HPT), introducing severe shear strain and high pressure and thus providing fine-grained microstructures. The consolidated composites were processed with two HPT revolutions. The results showed that the final microstructures and properties were primarily influenced by the carbon content within the prepared powder mixture; although the HPT-processed composites featured homogeneous fine-grained microstructures with the average grain sizes of 2–3 µm, the sizes of the graphene particles varied. The Vickers microhardness exceeded 100 HV0.1 for all the samples, and the electric conductivity varied between 98.8% and 102.1% IACS (International Annealed Copper Standard).

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Abstract: Nickel-based single crystal superalloys exploit a γ/γʹ microstructure, providing exceptional high- temperature strength and environmental stability, outperforming other known alloy systems. These properties make them useful for gas turbine applications. However, enhancing gas turbine efficiency requires higher operating temperatures, which place greater temperature and stress demands on these materials. One critical factor influencing their mechanical properties is the lattice misfit between the γ and γʹ phases. Consequently, extensive research has been dedicated to optimising lattice misfit values to achieve the desired mechanical performance. Accurate determination of lattice misfit is challenging due to the similar cubic crystal structures of the two phases. Conventional diffraction analyses are complicated by peak overlap of these phases, making precise peak position measurements difficult. To address this, a series of synchrotron X-ray, and neutron diffraction studies were conducted to explore the possibility of more reliable lattice misfit determination and how it varies across the microstructure as well as during deformation. Firstly, a monochromatic synchrotron X-ray source was used to investigate a high misfit Ni-based single crystal superalloy, which involved rocking the sample to ensure the Bragg condition was maintained during in situ loading at elevated temperature. Whilst this technique highlighted difficulties in fitting diffraction peaks where the Ewald sphere was not perfectly intersecting the reciprocal lattice point, it also revealed substantial differences in the lattice parameter when sampling regions across the γ/γʹ interfacial region and the bulk material. This suggested that further exploration of the interfacial region and the effect it has on the overall mechanical properties of the material is required. For this reason, a novel X-ray diffraction (XRD) approach utilising a synchrotron X-ray nanoprobe was developed to analyse local lattice parameters in the γʹ and γ phases. As a result of current technological constraints, and challenges in aligning single crystal superalloys to satisfy the Bragg condition, there were complications in accessing the diffraction signal. However, the method yielded reasonable results and demonstrated capabilities beyond those of conventional techniques that only probe larger volumes of material. Local misorientations and significant lattice parameter variations were observed, demonstrating the heterogeneity of the microstructure at smaller length scales. As such, future in situ studies using this technique appear promising. Whilst in situ heating experiments were unsuccessful in yielding diffraction data, the X-ray fluorescence (XRF) collected in conjunction demonstrated the potential for compositional analysis at elevated temperatures, particularly for polycrystalline or thermally unstable alloys. Additionally, pulsed source neutron diffraction was used to track lattice rotations during tensile deformation, employing a multi-peak 2D Gaussian fitting approach. While the measurements from this experiment do not directly indicate how slip progressed the extent of misorientation occurring during slip was successfully quantified. Furthermore, conventional fitting techniques were used to assess the evolution of lattice misfit during tensile deformation, corroborating the measurements obtained in previous studies. This research demonstrates both the challenges and potential of diffraction techniques for enhanced characterisation. While the deconvolution of γʹ and γ phase peak positions remains a significant challenge, valuable insights have been gained into stress gradients at interfacial regions and local misorientations within the microstructure. Furthermore, a foundation for methods to probe local microstructural changes and track lattice rotation during deformation have been established.