The turbocharger is an essential part of a modern diesel engine. The turbine wheel is a key component in the turbocharger and it should be designed to sustain at high temperatures and high rotational speeds during the hostile operating conditions and strenuous duty cycles. Mainly the material used in the turbine wheel is Inconel 713C which is a precipitation hardenable, nickel- chromium base cast alloy. The turbocharger manufactures' requirements imposed on this cast alloy is high as it should includes high fatigue and creep resistance at high temperatures as well as resistance to corrosion in a media containing products of fuel combustion. However, the turbine wheel blades are thermally and mechanically loaded during the operation of the turbocharger that can lead to material failures. With the objective to design safe components and improve fuel consumption, it is necessary to understand the failure mechanisms of the employed materials under these complex loadings. Different failure modes reported in literature, but the two most prominent turbine wheel failure modes are Low Cycle Fatigue (LCF) and High Cycle Fatigue (HCF). In general, there is uncertainty in literature about the exact influence of individual microstructure parameters including porosity, inclusions, grain orientation and slip activity on fatigue life of IN 713C alloy. In a complex system such as cast IN 713C alloy, these parameters should be identified and quantified. This needs complete description of the microstructure and microtexture of the alloys prior and post mechanical testing using various microanalytical tools including HR-SEM, HR-EBSD, EDX, X-ray micro-tomography as it suggested in this proposed study. Conventionally, the crack initiation and propagation during tension, creep and fatigue have always been correlated to some prominent microstructural features such as porosity, inclusions, voids, second phase particle, oxidation and surface conditions in most structure/property relationship studies. However, in a non-homogenous cast microstructure, the role of local zones/regions became very critical in materials performance and integrity. These local regions contain different grain/grain boundary distributions and local textures that create various microstructure/microtexture clusters that can promote/trigger crack initiation and provide fast crack propagation in some specific locations within the material. In this proposed study, along with defect distributions and surface condition of the alloy, other microstructure features including grain orientations, local/micro/macro/meso texture, strain distribution and grain boundary geometry/characteristics will be the focal points in understanding fracture mechanics, failure and deformation mechanisms. The aim of this study is to quantify and discriminate exact microstructural parameters that produced dissimilar crack characteristics in various zone/regions within a cast microstructure. Uniquely, here the parameters that caused crack formation at the surface will be quantified and compared with subsurface cracks and cracking in the bulk materials i.e., away from surface, edges and corners. Moreover, the crack formation in the absence of any microstructural defects will be characterised against the cracks formed in the vicinity of pores and inclusions. Identifying these microstructural parameters is fundamental in understanding the crack initiation and propagation correlation with microstructure and microtexture in cast alloys used at critical high temperature applications. Detailed investigation will be carried out in order to find exact interactions of the crack path, undulation and bifurcation with microtexture clusters that contain different strain/stress accumulations within the material. In this proposed study, in order to validate correlations between microstructure and crystallographic texture (local and global) with crack characteristic various micro-analytical tool will be employed.

Oil-free turbomachinery is an emerging technology defined as high speed rotating machinery that operates without oil-lubricated rotor supports. The term is generally understood to refer to gas-bearing technology, in particular, foil-air bearings. Such bearings support the shaft by means of an air cushion bounded by a flexible foil structure. The introduction of the foil structure resolves the problems associated with the very tight radial clearance required by a plain air bearing. With a foil-air bearing, while the shaft is stationary, there is either a slight clearance or a preload between shaft and bearing. As the shaft turns, a pressure is generated, which pushes the foil boundary away, allowing the shaft to become completely airborne. A solid lubricant coating on the shaft and/or top foil allows for the brief rubbing interval during start-up and shutdown. Recent technological breakthroughs in the USA in solid lubricant technology will enable the widespread use of such bearings in turbomachinery, particularly gas turbine machinery. This has resulted in intensive research in oil-free turbomachinery motivated by its technological and environmental benefits for both military and civil applications (e.g. turbochargers that run up to 180,000rpm and engines for small aircraft). As stated by NASA, the foremost challenge for this technology is the design of an oil-free turbine engine to power 21st century aircraft .Foil-air bearings, like conventional oil bearings, are nonlinear elements that are capable of introducing undesirable nonlinear effects into the dynamic response of the system. These effects may involve sudden jumps in the vibration amplitude, non-synchronous vibration and self-excited vibration. These effects exacerbate vibration and introduce fatigue. Hence, to guarantee structural integrity, the deployment of these bearings in practical machinery necessitates rotordynamic analysis that takes account of the bearing nonlinearity. The ability to make reliable quantitative predictions of such effects enables the engineer to account for/mitigate them in the design. Moreover, such analysis provides the basis of a much-needed knowledge database for in-service monitoring. However, such calculations are hampered by the prohibitive computational cost introduced by the complexity of the bearing model. Consequently, dynamic analysis has so far been restricted to a highly simplified rotordynamic system. The proposed project researches novel methods that enable the efficient nonlinear dynamic analysis of practical oil-free turbomachinery. These methods will be experimentally validated in a study that provides a much-needed insight into the nonlinear dynamics of such systems. The deliverables of this project will be:i. A suite of computer software algorithms for efficient nonlinear dynamic analysis based on three novel approaches (Galerkin reduction, Harmonic Balance, System Identification). ii. An original-design test-rig for experimental validation of the computational methods.iii. A report on the validation of the methods, focussing on both computational and experimental issues.The proposed research is novel since: (a) It will give the UK a foothold in oil-free turbomachinery technology, raising the UK's scientific profile - such research has to date been confined mainly to the US; (b) It will research the prediction of the nonlinear dynamics of practical oil-free turbomachinery (e.g. an oil-free turbocharger); (c) It will do so through the three novel approaches mentioned above; (d) It will produce an original-design test-rig for the validation of the methods developed and investigation of nonlinear phenomena.The work will be carried out by a post-doctoral researcher over a period of three years.

The UK engineering coatings industry is worth over £11bn and affects products worth £140bn. The vision of this project is to create internationally unique multi-purpose PVD/PECVD coatings system which will enable innovation in advanced science of future hybrid coatings. This new facility would be built on the existing Leeds coating platform capability and would create system with no similar functionality available internationally. Using existing Leeds coating platform we can already deposit carbides, nitrides and diamond-like carbide (DLC) coatings, and we are exploiting this mainly for tribological applications with automotive, energy and lubricant companies. With this investment, we will be able to additionally process novel nanocomposite coatings, next generation of DLC coatings (with incorporated nanoparticles), advanced optical coatings and sensor coatings, carry out functionalisation of powders, barrier layers, coatings on polymers and coatings on complex shapes. This proposal aligns with a major new initiative at the University of Leeds to create an integrated gateway to Physical Sciences and Engineering by investing in the collaborative Bragg Centre that will house new state-of-the-art research facilities for the integrated development, characterisation and exploitation of novel advanced functional materials. This proposal also coincides with Leeds University investment in the Nexus Centre - a hub for the local innovation community as well as national and international organisations looking to innovate and engage in world-leading research. The upgraded coating platform would play a strategic role in the UK Surface Engineering landscape and complement existing national facilities. It would form a part of the new Sir Henry Royce Institute for Advanced Materials, of which Leeds is a partner. The configuration of the new instrument is designed to be versatile and serve a wide range of internal and external users with widely different classes of advanced materials. A number of specific activities have been planned to ensure that potential beneficiaries have the opportunity to engage with new coating facility. The economic competitiveness of the UK's manufacturing industry will benefit from new, commercially exploitable IP in novel cutting-edge Surface Engineering technology. Members of an academic community and industry will be able to benefit directly from the proposed research and generated new knowledge. They will gain new skills and know-how related to the latest advancements of PVD technologies. Improved adoption of Surface Engineering will result in wider UK PLC economic and societal impacts associated with development of functional surfaces for automotive, aerospace, biomedical, healthcare, defence, agriculture, oil & gas and packaging industries.

This is an application for a Doctoral Training Centre (DTC) from the Universities of Sheffield and Manchester in Advanced Metallic Systems which will be directed by Prof Panos Tsakiropoulos and Prof Phil Prangnell. The proposed DTC is in response to recent reviews by the EPSRC and government/industrial bodies which have indentified the serious impact of an increasing shortage of personnel, with Doctorate level training in metallic materials, on the global competitiveness of the UK's manufacturing and defence capability. Furthermore, future applications of materials are increasingly being seen as systems that incorporate several material classes and engineered surfaces into single components, to increase performance.The primary goal of the DTC is to address these issues head on by supplying the next generation of metallics research specialists desperately needed by UK plc. We plan to attract talented students from a diverse range of physical science and engineering backgrounds and involve them with highly motivated academic staff in a variety of innovative teaching and industrial-based research activities. The programme aims to prepare graduates for global challenges in competitiveness, through an enhanced PhD programme that will:1. Challenge students and promote independent problem solving and interdiscpilnarity,2. Expose them to industrial innovation, exciting new science and the international research community, 3. Increase their fundamental skills, and broaden them as individuals in preparation for future management and leadership roles.The DTC will be aligned with major multidisciplinary research centres and with the strong involvement of NAMTEC (the National Metals Technology Centre) and over twenty companies across many sectors. Learning will be up to date and industrially relevant, as well as benefitting from access to 30M of state-of-the art research facilities.Research projects will be targeted at high value UK strategic technology sectors, such as aerospace, automotive, power generation, renewables, and defence and aim to:1. Provide a multidisciplinary approach to the whole product life cycle; from raw material, to semi finished products to forming, joining, surface engineering/coating, in service performance and recycling via the wide skill base of the combined academic team and industrial collaborators.2. Improve the basic understanding of how nano-, micro- and meso-scale physical processes control material microstructures and thereby properties, in order to radically improve industrial processes, and advance techniques of modelling and process simulation.3. Develop new innovative processes and processing routes, i.e. disruptive or transformative technologies.4. Address challenges in energy by the development of advanced metallic solutions and manufacturing technologies for nuclear power, reduced CO2 emissions, and renewable energy. 5. Study issues and develop techniques for interfacing metallic materials into advanced hybrid structures with polymers, laminates, foams and composites etc. 6. Develop novel coatings and surface treatments to protect new light alloys and hybrid structures, in hostile environments, reduce environmental impact of chemical treatments and add value and increase functionality. 7. Reduce environmental impact through reductions in process energy costs and concurrently develop new materials that address the environmental challenges in weight saving and recyclability technologies. This we believe will produce PhD graduates with a superior skills base enabling problem solving and leadership expertise well beyond a conventional PhD project, i.e. a DTC with a structured programme and stimulating methods of engagement, will produce internationally competitive doctoral graduates that can engage with today's diverse metallurgical issues and contribute to the development of a high level knowledge-based UK manufacturing sector.

The vision of the proposed EPSRC Centre for Innovative Manufacturing (CIM) is to break new ground by creating the concept of the factory on the machine to deliver to UK industry disruptive solutions in advanced manufacturing for the next generation of high added-value products. Embracing and developing the factory on the machine concept will be a critical step in enabling a sustainable manufacturing sector for the next generation of engineered products dependent on precision and micro/nano scale geometrical accuracy and functionally optimised surfaces.Key challenges to achieving the concept of the factory on the machine are: Challenge I: Elevation of machine tool accuracies beyond the present formidable barriers to those currently only achievable by advanced metrology equipment in stable operating environments, through embodiment of our leading research in machine error modelling and reduction. Challenge II: Building sound foundations for the factory on the machine by developing new metrology instrumentation, used within the machine environment and a novel toolkit, for geometrical characterisation (size, geometry and texture) for the next generation of engineering products.In order to answer the challenges and vision of the CIM, the overall research programme is divided into key research themes and platform type activities. The two major thematic areas of research within the CIM are:Theme I - factory on the machine : to create a configurable and scalable platform for implementing advanced manufacturing and measurement technologies on machines ranging from nano, micro to large volume capability. Analogous with the lab on a chip concept, the delivered system will fuse production capability with high-precision metrology to provide an automatic quality control feedback loop for both product quality and machining process sustainability. Theme II - underlying techniques for factory on the machine : The aim here is to create new measurement and specification methodologies and products (smart software and hardware systems) and to deliver an underpinning new technology in measurement science for micro/nano scale surfaces on macro/meso dimensioned objects with Euclidean or non-Euclidean (non-rotational and non-translational symmetry) geometry and deterministic texture all to be applied within the factory on the machine environment. Platform activities will encompass: (i) Retention and recruitment of key identified research and technique staff; (ii) Generation of new knowledge and instrumentation derived from fundamental EPSRC, EU and TSB funded research projects (iii) Support blue sky research and feasibility studies in machine tool/surface technology and (iv) Knowledge exchange to key partners through specific projects, collaboration agreements, licensing, workshops, training, national networks, sand pits and open days. Platform activities will be targeted towards key partners firstly, their supply chains/end users, then secondly wider sectors of UK industry, as well as national and international standardisation bodies. Overall, this CIM research will link measurement and production in a unique way to minimise cost whilst at the same time enabling the manufacturing base to meet the challenge of ever increasing complexity and quality in manufacture. It will provide coherent research solutions to the manufacturing sector to ensure that advanced UK manufacture is at the forefront of emerging technologies. Partnership with UK industry will provide a research focal point, a national network to disseminate the outcomes and a link with other networks, CIMs and IKCs to ensure that the research provides the required outputs to drive industry forward. This would boost the capabilities of the project proposers to an unrivalled and unique position within the field of machine tool accuracy and surface metrology, allowing the research team to command a global leading role in the foreseeable future.