APPLICATION OF AN ACOUSTIC EMISSION METHOD FOR SCC TESTING OF ZIRCONIUM CLADDING TUBES

摘要

Procedure and equipment have been designed to implement an assessment of propensity to SCC(stress corrosion cracking) for thin-walled cladding tube. The assessment is based on a schema ofcorrosion tests conducted in a localized zone of contact of a material with an aggressive environmentwhich allows tracing the evolution of single corrosion defects through AE (acoustic emission)measurements. Based on these measurements during testing for 8 hours two stages were revealed in theprocess of tube SCC. The developed procedure of SCC testing in the local zone of corrosion inducedfracture based on AE measurements allows the analysis of the mechanism and kinetics of fracture in realtime which substantially shortens the time of corrosion tests. Thin-walled zirconium tubes havingdifferent structural states were comparatively tested. The influence of structure factors on kinetics andresistance to SCC was demonstrated.