Chromium-coated Zirconium alloys for Accident Tolerant Fuel Cladding

An important aspect of nuclear reactors is the safe operation of the so-called fuel assemblies, i.e. the bundled fuel rods. In a modern water-cooled reactor, the material of choice to encapsulate fuel is Zirconium-based alloys. They display excellent performance during normal operating conditions but, as Fukushima has shown, do not protect the fuel sufficiently during accident scenarios. Consequently, there is a world-wide search for new material systems that provide the same normal operating performance but also protect the fuel during abnormal operation. The most likely system to succeed is metallic-type coating on Zirconium alloys as it represents the most robust material solution for a safety critical component. Recent research by CEA and Westinghouse has particularly demonstrated the potential of Cr-based coating as it would not only perform significantly better during off-normal conditions but also shows far superior corrosion performance and reduced hydrogen-pick up in aqueous environment at typical operating temperatures. However, development in this area is at a very early stage and to date there is no understanding of the performance of such material system when exposed to radiation.

The PhD project is co-sponsored by Westinghouse, a leading fuel manufacturer based in the UK, Sweden and the US. The University of Manchester has the largest university-based nuclear research activity in the UK and also the largest university-based Zr technology group worldwide. Further, Manchester has world-leading material characterisation capabilities and irradiation facilities.

The PhD project will investigate a range of manufactured coatings on Zr-alloys in respect of their irradiation and corrosion resistance. The project will benefit from state-of-the-art characterisation tools such as advanced electron microscopy and x-ray diffraction techniques and use Manchester’s Dalton Cumbrian Facility to irradiate material by means of protons. Overall, the aim is to develop an understanding of the effect of simulated nuclear environment on the coating and coating/substrate interface. Based on such new understanding, assessments will be possible to identify the most promising system.

This project is suitable for students with a background in physics or mechanical engineering.

Advanced Metallic Systems CDT
The Advanced Metallic Systems CDT is a 4 year programme hosted jointly by the universities of Manchester and Sheffield building on their complimentary expertise and international reputations in materials science and engineering research. In year 1, students from a range of disciplinary backgrounds undertake taught courses in core materials topics. Doctoral research begins after 6 months. Our transferable skills and personal development programme leads to a Diploma in Professional Skills. Visit our website for more information www.metallicsCDT.co.uk.