PCI has historically resulted in a large number of fuel failures in BWRs but also to some extent in PWRs. The introduction of various remedies such as power change operation restrictions and liner/barriers in BWRs has reduced the number of PCI failures. However, there are some recent fuel failures in both BWRs and PWRs that has put the PCI failure mode in focus again. The objective of this report is to give a better understanding of the PCI mechanisms, pertinent methods to test PCI performance and PCI remedy technology may improve fuel reliability and reactor safety.
Adequate mechanical properties are crucial for satisfactory fuel assembly performance: 1) in-pile under normal operation, anticipated operational occurrences and accident conditions as well as, 2) under intermediate storage conditions. The objective of this report is to provide the basic understanding of the mechanical properties of the fuel components that are crucial for the fuel in-pile performance.