Access to Royce’s world class facilities proves instrumental in PhD student’s research into nuclear reactor design
Royce’s unique characterisation equipment is proving crucial in developing our understanding of material behaviour, with our open and accessible research culture attracting students from across the country.
Siqi He is a PhD researcher at the University of Bristol studying the microstructural damage of advanced gas nuclear reactor steel during forward creep and stress relaxation.
During research into the size, number and distribution of creep cavities in steel used in AGCRs, it became apparent to Siqi that the characterisation techniques available at hand weren’t able to provide the comprehensive set of results necessary to really make an impact. X-ray CT provides limited resolution of around 0.5mm in either axis and gallium Focussed Ion Beam (FIB) lacks the milling rate to give enough data for a 3D construction of the creep cavities.
Access to the Royce’s PFIB proved crucial in advancing my research – we got to the point where we realised that if we only used the equipment available to us, we would be unable to investigate the material fully and produce research of lesser quality for it. The Royce PhD Access Scheme is a fantastic opportunity for students to push the boundaries of their research by access to world leading equipment and renowned technical expertise.
Through the Royce’s PhD Access Scheme, Siqi was able to use the Royce’s FEI Helios Plasma Focussed Ion Beam at the University of Manchester. After training from experienced Royce technicians, Siqi used the PFIB to construct a 50x50x50 μm3 3D model of the scanned area, triple the volume of the dimension that could otherwise be achieved with conventional FIB scanning.
Crucially, the increased capability provided by the PFIB allowed for 3 other defects to be detected in the same volume as the creep cavity; creep cavities at austenite grain boundaries, creep voids linked with retained carbide precipitate regions and Manganese Sulphide inclusions. Working with the Royce PhD Access Scheme widened the scope of Siqi’s research and has formed the basis of a number of papers he has written.