Deformation-corrosion interactions for Zr alloys during I-SCC crack initiation - Part I: Chemical contributions

For a better understanding of the initiation step of iodine-induced stress corrosion cracking in Zr alloys, responsible for pellet-cladding interactio n (PCI) fuel rod failures, an analytical study has been undertaken, the aim of which being focused on the respective roles of local chemistry and stre ss/strain state on the crack nucleation. This first part is mostly related to the chemical environment. From the tensile tests performed under iodine rich and inert environments, it was concluded that no crack initiation coul d be detected following the tests in an inert atmosphere. The iodine induce d stress corrosion initiation mechanism must therefore be analysed as a cor rosion-strain interaction. (C) 1999 Elsevier Science B.V. All rights reserv ed.