Iodine-induced stress corrosion cracking (SCC) of zirconium cladding tubes is a well
known problem inherent in fuel cladding operation in nuclear reactor core. In the present
work we have applied a previously developed approach of SCC-testing of zirconium
cladding tubes which includes acoustic emission measurements, fractography and
metallographic a n a lysis to study how the zirconium alloy strength influences t h e
mechanisms, kinetics and overall resistance of cladding tubes to iodine-induced SCC. A set
of different alloy claddings having different strength (yield strength and ultimate tensile
strength) have been comparatively tested for SCC. Claddings have been manufactured
from different industrial zirconium alloys and have been tested as-received. It has been
shown, that zirconium alloy strength increases the susceptibility of claddings to SCC via
changing mechanisms and kinetics of SCC.
Keywords: zirconium alloy, fuel cladding, stress corrosion cracking, acoustic emission