A prestigious OECD project run by Studsvik since 2004, which had a second phase, SCIP II in 2009, will continue now for another five years. This is the international fuel test program SCIP (Studsvik Cladding Integrity Project) with participants from Europe, Russia, Japan, the US and Korea. Studsvik will continue in the role of operating agent for SCIP III.

The main studies conducted as part of the SCIP projects concerned hydrogen-related failure mechanisms for fuel cladding, mechanisms leading to fuel failures driven by PCMI in particular failures due to stress corrosion cracking (pellet-cladding interaction, PCI). Modelling has also been carried out to simulate how the fuel and cladding is affected during reactor operation.

And now, in the SCIP III, the fuel fragmentation, relocation and release during off-normal temperature transient, LOCA, the fuel and cladding response to transient leading to cladding overheating, and the mitigating effect on PCI of the ramp rate and oxygen, will be studied. All of this still keeping the support of the modelling.

In the project different cladding materials are tested, mainly by means of microscopy studies, mechanical testing, semi-integral test and reactor tests. It is conducted in the form of experiments, studies of fundamental mechanisms, development of suitable testing methods and knowledge transfer.  

The results are used to support the nuclear community, vendors, authorities, utilities and laboratories in assessing margins and increasing the nuclear fuel safety.