JOINT: an Indo-UK collaboration in joining technologies

The renaissance in new nuclear build in the UK and overseas has created the opportunity to develop new approaches for the manufacture and joining of nuclear components. Developments in joining technologies, including laser hybrid welding for thin metallic sections, diffusion bonding for dissimilar material systems, narrow gap fusion welding for dissimilar metals, friction-stir welding of materials for structural applications, and electron beam welding for thick sections, offer significant benefits over traditional welding techniques; creating improved microstructures, lower residual stresses and benefits in inspectability. These combine to create joints that contain fewer defects and exhibit superior performance in the challenging environment of a nuclear reactor.JOINT aims to identify and optimise advanced joining technologies through a strategic collaboration between UK academic expertise (at the Open University, Manchester University, Bristol University and Imperial College) and Indian atomic research institutes (BARC and IGCAR). All parties have a proven track record in driving developments and improvements in joining technologies and the collaboration will integrate strengths in joining technologies, state-of-the-art characterisation and joint performance testing. JOINT thus brings together partners of international reputation who are at the forefront of joining technologies and have a proven track record of access to high-end national and international facilities relevant to the project, e.g. ISIS, DIAMOND, ILL etc. JOINT will pioneer new and advanced joining technologies by optimising fabrication parameters, microstructures and mechanical properties for the reliable performance of a variety of metallic and non-metallic material joints of relevance to present and future reactor systems. Such optimisation will require among other things narrow heat affected zones, low residual stress, strain and distortion with minimum and quantifiable risk of joint defects. Developments will draw on advanced modelling approaches to simulate and predict joint characteristics, materials examinations to understand the nature of the materials of the welds and adjacent materials, experimental methods to investigate the mechanical performance, such as strength and fatigue resistance, and Non Destructive Evaluation methods to find and characterise defectsA 5 - 10 year programme of research collaboration is envisaged covering a wide range of advanced joining technologies. THe JOINT consortium will focus activities grouped under the following eight Work Packages (WP). A UK or Indian partner will lead each WP building on the strengths of each country: WP0 (lead: UK): Work planning, coordination and managementWP1 (lead: India): Pre-joint materials characterisationWP2 (lead: India): Joining technologiesWP3 (lead: UK): Post-joint characterisationWP4 (lead: UK): Joint performanceWP5 (lead: India): Joint simulation and modellingWP6 (lead: UK): Assessment and dissemination WP7 (lead: India): Foresight and future programmesThe present proposal covers the initial 3-year programme of research activities that will focus on three joining technologies: laser-hybrid welding, diffusion bonding and low vacuum electron beam welding. Although WP5 falls outside the scope of the present proposal it will be covered by sharing existing research programmes at JOINT meetings and exploiting emerging funding/collaboration opportunities. The unique opportunities provided by the JOINT consortium are the complementary nature of India's joining technology expertise and the UK's weld characterisation expertise. The research which is necessary to bring new joining technologies into nuclear plant design can only be achieved by a programme of interdisciplinary research. The JOINT consortium brings together the necessary complementary expertise.

Two recent Nuclear Industry Association (NIA) studies on the UK capability to deliver a new nuclear build programme ( The capability to deliver a new nuclear build programme , NIA Report, 2006 and The UK capability to deliver a new nuclear build programme 2008 Update , NIA Report, 2008) highlight the major importance of the materials supply chain to new nuclear build and the strengths and weaknesses of the UK materials capability for the manufacture and fabrication of components. The NIA study considered the area of 'Plant and Equipment' to be of most relevance to the materials supply chain. The report indicates that 'Plant & Equipment' typically comprise approximately 55% of a nuclear power plant build. The NIA reports suggest that current UK industry capability is to support approximately half of the 'Plant & Equipment' necessary for new nuclear power plant build. With investment, they considered that this may be expanded to approximately 70% of the required 'Plant and Equipment' capability. This points to the potentially important role investment in the materials supply chain could play in exploiting the opportunities that are arising from new build. Part of this investment relates to the rapid uptake of new manufacturing technologies in the supply of components for the next generation of nuclear power stations in the UK, Europe and overseas. It is therefore critical that relevant research finds a rapid path through development and prototyping to application. Research undertaken within JOINT will primarily benefit the manufacturing supply chain for nuclear build in the UK and India. The development of advanced joining techniques that minimise heat affected zone regions that may be susceptible to degradation mechanisms including stress corrosion cracking and corrosion-fatigue (e.g. through the sensitisation of grain boundaries due to chromium carbide precipitation) will be of major importance to the fabrication of the new generation of nuclear power stations. Research into laser hybride welding, diffusion bonding, alongside other joining technologies including electron-beam welding, will be of particular benefit to the manufacturing companies that aim to supply nuclear components. UK companies that will benefit from the research include the following: 1. Control Rod Drive Mechanisms and Reactor Internal Components: Assystem UK Ltd, NIS Ltd, Doosan Babcock, Weir Strachan & Henshaw, Alstec Ltd and Bendalls Engineering Ltd. 2. Pressuriser components, piping and forgings: Sheffield Forgemasters International Ltd., Wyman-Gordon, Rolls-Royce Nuclear, Goodwin Steel Castings Ltd., Bradken Ltd., Proclad International Forging, Ltd., Shaw Group 3. Pumps: Sulzer Pumps (UK) Ltd., Weir Valves & Controls (UK) Ltd., Thompson Valves, Ltd., William Cook Cast Products These UK companies, alongside Indian manufacturing supply chain companies will link to the the JOINT programme either directly or, most appropriately, through the new Nuclear Advanced Manufacturing Research Centre (Nuclear AMRC) established by the Universities of Sheffield and Manchester through Central and Regional Government funding of over 33 million. The Nuclear AMRC aims to equip the UK manufacturing supply chain to supply nuclear components through training, accreditation and the rapid take-up of research developments which are relevant to new nuclear build. The Nuclear AMRC has a tiered membership scheme that bring's together reactor vendors and component suppliers, and facilitates the rapid progression of research through development to application - thus enhancing the UK manufacturing base to supply into the global new nuclear build programme. Through The University of Manchester, research developments within JOINT will find a rapid route to market through the Nuclear AMRC.