Ceramic SHaping: extrusion of glAss Preforms for new fibres in hEalthcare (SHAPE) The Aim of this Project is to achieve unprecedented advances in novel glass extrusion in order to make brand new shapes of glass preforms. These preforms are needed for drawing to next-generation structured glass fibres for two targeted healthcare applications - bioimplant glass fibre for therapeutics and MIR (mid-infrared) glass fibre lasers for cancer detection. 1. Glass extrusion What is glass extrusion? Heat glass above its glass transition temperature (Tg) and a viscous liquid forms. This liquid has treacle-like consistency and can be shaped by forcing it through a shaped metal die. For instance, a die with a hole produces a rod-shaped extrudate. The extruded rod is allowed to cool, and stiffens at Tg to form a glass-rod preform, which is taken to a draw tower and, in a separate operation, drawn to form glass fibre of the ~ diameter of a human hair. Co-extrusion, through the hole in the die, of two glass billets of different glass composition, but with matched thermal properties, forms a glass-rod preform with an internal core of different glass through it. Along part of the preform length, the internal core of glass occupies approx. constant 85 % of the diameter. When this is drawn to fibre, the fibre similarly has a large core of glass occupying 85 % of the diameter. The core/cladding interface is excellent optical quality, having mated during the extrusion itself. However, only 20% of the extruded rod preform is usable, as the core inside the rest of the preform is too tapered. Extrusion through a spider-die can produce a glass preform in the shape of a small-orificed tube. If a cane of different glass is now threaded through this tube, this whole can be drawn to fibre with a small core running through it and occupying less than ~ 20 % of the fibre diameter. Such small core fibre is vital to achieve fibre lasing. However, this processing route makes inferior optical quality core/cladding interfaces and can take several weeks. 2. MIR fibre This Project will enable straightforward manufacture of high quality small-core fibre vital for MIR-glass fibre lasers. We will extrude small-core glass-rod preforms with core less than or equal to 20 % diameter, constant over least 50 % of the preform, with core/cladding mating during extrusion to give excellent optical quality of the core/cladding interface. To achieve this breakthrough, we will invoke, for the first time, extrusion of pre-shaped glass billets, and also indirect glass extrusion - overlooked since its invention ~50 years' ago. MIR light distinguishes diseased tissue, including cancer, by detecting the molecular-makeup of the tissue. Using MIR fibre-optics will enable a new type of endoscopy so that during cancer surgery the surgeon can guide MIR fibre laser light onto the tissue and collect the reflected light to molecularly map the tissue and instantly tell if all cancer is removed. Compact MIR fibreoptic systems will be enabled by using MIR broad- and narrow-band fibre lasers; for these, small-core MIR fibre is essential and this Project will enable the new extrusion technology to make this possible. 3. Biocompatible, therapeutic fibre The human body does not reject biocompatible fibre. We will extrude new types of multi-layered and holey biocompatible glass preforms for bioimplant fibre of finely controlled dissolution rate in the body. This is for therapeutic drug and ion release from fibre at the site of body infection and for controlled dissolution fibre-biocomposites to implant in the body to support bone-healing. 4. Project synergy This Project will encourage cross-fertilisation of ideas, for instance a bio-compatible glass cladding for MIR glass fibres may be beneficial and using biocompatible glass fibres for NIR (near-infrared) light transmission has the potential to allow in situ monitoring of tissue health in vivo.

Summary Mass finishing [MF] describes the numerous range of processes used to modify and enhance the surfaces of engineered parts by immersion in a fluidized circulatory flow of loose abrasive media. There are many different types of MF operations in use including: vibratory, tumbling and centrifugal disk which are responsible for material removal and the range of finishing actions from surface cleaning to deburring, often imparting a smooth, lustrous finish. The MF process is particularly suitable for irregular shaped parts and/or large batch sizes and is gaining widespread acceptance as a critical operation for super-finishing components in the fields of aerospace, auto-sport, biomedical and space industry engineering. However, the process has attracted only little research and as a result the potential of the process is far from being fully exploited and current design practices tend to be empirical, strongly reliant on user experience and expertise. The aim of this study is to improve: (i) understanding of particle kinematics, (ii) process performance and capability, and (iii) evolution of surface finish thus adding a scientific basis, presently lacking. This proposed research will be the first to include study of the highly efficient Drag finishing regime wherein a part is 'dragged' through static media at high speed. A major feature of the work will be the discrete element modelling programme, the outcomes of which will have strong generic relevance to the wider areas of fluidized and bulk particle/ granular flows. Given the absence of any major UK or European research effort in this field, a key aim will to be to establish, at LJMU, a unit of expertise in MF that will act as a knowledge warehouse and a conduit for dissemination of best practice and which and will seek to contribute to regional and national strategic planning aimed at promoting and sustaining economic growth in manufacturing industry. The aims of this research are as follows: to secure and deliver to industry the necessary scientific grounding required to advance and exploit the MF process to gain new understanding of impact, wear and surface evolution phenomenon in MF processes to develop a tribological based abrasion model for mass finishing to found a 3-D DEM capability for simulation of vibratory-fluidized flows to establish at LJMU a demonstrator facility directed at key application areas To achieve these goals a world class partnership of experts are brought together coupling manufacturing knowledge with academic and technical expertise including the high value manufacturing catapult, the MTC, and the rapidly progressing joint initiative: MTC@LJMU. Funding support from EPSRC will help ensure that UK industry and academia lead the world in this rapidly developing and important technology. The planned outreach programme will strengthen this action of dissemination to, and engagement with, industry, and serve to coordinate the knowledge transfer.

Bonding optical materials (glasses, crystals) to other optical or structural materials (metals, ceramics) is a key manufacturing challenge for many optical devices, as clearly articulated by our industrial partners. Our solution is to use an ultra-short pulsed laser welding process that has shown great promise but currently requires many months or even years of detailed experiments for each new material combination and geometry. Hence applications are currently limited to components made from borosilicate glasses or quartz welded to aluminium alloys and stainless steel, of typical dimension 10 mm. In this project our drive is to extend the process to new combinations of materials (including important IR materials) and shapes. To achieve this, the project will take a multi-pronged approach: (i) to create the modelling and sensing tools essential for rapid process optimisation; (ii) to engineer a new optimised laser source based on emerging 2 micron wavelength technologies, pioneering the welding process for IR optical materials; (iii) to research concepts for engineering the interface and weld/joint geometry to reduce the impact of differential thermal properties of the two materials; and (iv) to investigate scaleable welding approaches for larger parts e.g. continuous meander patterns and dynamic clamping. Finally, we will undertake a series of proof-of-principle experiments to determine the suitability of the process with a wide range of material combinations, directed towards our industrial partners' applications. Our programme of manufacturing research is aligned with the interests of our industrial collaborators, together with the academic drivers of laser material interaction knowledge, process understanding and process control. Our ultimate goal is to develop this welding process into a truly flexible and generic solution for joining optical to structural materials at a range of scales.

A world where nuclear fusion helps meet humanity's energy needs is now within reach but there is still no way of "seeing" the operation of fusion reactors in real-time, presenting critical operational and safety risks. This project will lead to a disruptive new sensor technology enabling monitoring of the operation of fusion reactors in real-time, directly addressing this urgent need. Nuclear fusion will become a commercial proposition in the next decade revolutionising energy generation to supply abundant, clean energy. Conditions for light nuclei to fuse are extreme: hot plasma is held at 150-200 Million C by powerful magnets. This is accompanied by emission of highly energetic fast neutrons with 14.1 MeV energy. Materials adjacent to fusion reactions must tolerate very high temperatures and damaging neutrons so developing sensors and sensor materials capable of measurements in such conditions are among the greatest challenges. This project will directly address these urgent drivers by delivering an entirely new class of durable inorganic glass scintillators, which convert neutrons to detected photons. These will be capable, for the first time, of detecting fast 14.1MeV neutrons emitted from fusion reactions at high temperatures, enabling real-time insight into operation of fusion reactors, far advanced from current state-of-art. This is timely as UK fusion transitions from lab- to pilot- to commercial-scale (e.g. STEP) as the need for real-time, robust sensors capable of years of operation is urgent. Measurement methods for neutron flux in high intensity areas are few and new approaches are needed for next generation tokamaks. Fission chambers and gas filled detectors are fragile and surveillance foils do not provide real-time information. No technology yet exists capable of doing what we are attempting. Our novel sensors will enable a step-change by providing operators real-time measurements in extreme environments, accelerating design processes and enabling more efficient and advanced control mechanisms, greatly enhancing safety. Inorganic glasses can be produced at scale and are tolerant to damaging neutron radiation and high temperatures. However, current inorganic glass sensors cannot reliably detect fast 14.1 MeV neutrons from nuclear fusion as there is little scintillation. Plastic and liquid scintillators (including organic glasses) are sensitive but have very low tolerances to high temperatures and radiation damage. Developmental diamond-based sensors are small (< 5 cm) and cannot be produced at scale. Our new inorganic glasses capable of detecting fast neutrons will bring game-changing advances in neutron detection for fusion energy. The most exciting potential rewards of this high-risk project will be acceleration and enhancement of development, design, construction, and operational safety of commercial nuclear fusion power plants to be built in the UK and globally in the next decade.

SeaMatics is an "advanced materials manufacturing project for photonic integrated circuits" for a range of emerging applications in optical communication, sensors, imaging technology for healthcare, and lighting. Unlike the integration in electronic circuits in which electrons flow seamlessly, in photonic integrated circuits at the light does not flow seamlessly due to mismatch of refractive index and materials dissimilarity. In order to facilitate a way forward for fabricating light circuits, the SeaMatics team has embarked on research which will exploit a novel "ultrafast laser plasma implantation (ULPI)" based technique for fabricating complex structures, using following materials: rare-earth ion doped glass, polymers and silicon and GaAs semiconductors. Such a combinatorial approach for materials fabrication will yield photonic circuit for engineering range energy-efficient devices for cross-sectorial applications (health, manufacturing, energy, digital). The project is led by the University of Leeds and is supported by has four academic partners by the Universities of Cambridge, Sheffield and York in the respective areas of research on polymeric devices, III-V semiconductors, and silicon photonics. The EPSRC National Centre for III-V Technologies will be accessed for materials and device fabrication. Eleven industry partners directly involved in the project are: DSTL, GTS/British Glass, Glucosense/NetScientific, Product Evolution, PVD Products, CST, IQE, Dow Corning, Xyratex, Gooch and Housego and Semtech. The industry links covers from materials manufacturing to optical components and their applications in optical/data communication, sensors for healthcare, energy for lighting. In this partnership the manufacturing is linked with different levels of supply chain, which we aim to demonstrate by researching on exemplar devices as end points. The main goals of the project are a) Set up a ULPI manufacturing capability at Leeds which will serve the needs of academic and industrial communities in UK to start with and then expand for international collaboration. b) Our first application led manufacturing example will demonstrate ULPI based RE-earth doped glass photonic circuits with light splitting, lasing and amplification functions on a chip. c) In another example we will demonstrate electrically pumped semiconductor lasers (VCSEL and VECSEL) and integrated with rare-earth ion doped glass for broadband and tunable lasers. d) Approaches developed in b) and c) will be then expanded for manufacturing larger scale photonic integrated circuits on silicon, embodying multiple functions using the techniques developed in a). e) ULPI as technique will be applied for engineering novel range of polymer-glass sensor devices which will be used for health care. f) The final goal of project is to provide training, dissemination, and outreach opportunities for new researchers in SeaMatics. Dissemination related activities will be via the standard peer-review publications in prestigious journals, conferences and workshops. Dedicated symposia are planned for dissemination, and also the outreach activities involving UG/PG interns, PhD students and Sixth form pupils.