In 2014 the discovery of cracking in an austenitic weld led EDF Energy to temporarily close 4 of these reactors, each capable of generating £700k of electricity per day. As part of their long-term programme EDF Energy and the Open University have been using the SANS2D instrument at ISIS Neutron and Muon Source to understand how cracks propagate in these austenitic welds, with the aim of improving how welds are assessed in safety critical systems and whether reactor lifetimes can be extended.
The Open University and EDF Energy have a long history of collaboration. The team used the Industrial Collaborative Research and Development (ICRD) programme at ISIS to study a sample of austenitic weld material to understand creep crack growth behaviour in the heat affected zone (HAZ). It is difficult to determine how cracks develop and the role of cavities in these samples by conventional microscopy, so they proposed using small angle neutron scattering to measure the degree of cavitation and distribution of cavities in the vicinity of the HAZ crack.
Hedieh Jazaeri from the Open University was the Principal Investigator on the project. She says, “Using SANS2D we were able to successfully measure the extent of cavitation damage up to about 300nm around the crack. This has provided EDF Energy with a much better understanding of crack propagation. When each AGR can generate £700k electricity a day, extending their lifespans has a significant impact on the UK economy and the security of energy supply."
See here to learn more on our instrument SANS2D.
For further information on beamtime for industry see here or contact our industrial liaison Dr Christopher Frost via email or on +44 (0)1235 445296 for further information.