X-ray imaging detects 80-nanometer pores in nuclear fuel cladding

Researchers at Switzerland's Paul Scherrer Institute used ptychographic X-ray computed tomography at the Swiss Light Source to map corrosion in nuclear fuel rod cladding in 3D, detecting pores as small as 80 nanometers. Samples cut from spent cladding tubes stayed leak-tight, and protective oxide layers kept working after years of reactor operation.

• PXCT at the Swiss Light Source resolved pores down to 80 nanometers in the oxide layer
• Cylindrical samples just 20 micrometres wide were cut from spent fuel cladding
• Density of reactor-used samples matched autoclave lab corrosion tests
• Cladding is over 98% zirconium and remained leak-tight after service