Fractographic Aspects of Stress Corrosion Failure of Zircaloy 2 in CH3OH HCL Solutions

Abstract

Fracture surface of Zircaloy-2 specimens tested under constant crosshead speed in CH3OH/0.4 Vol. %HCI solution with and without selenium (25 ppm) addition was studied. Using a combined process of deformation and annealing, coarse grained material was also obtained and examined. Two modes of stress corrosion crack propagation were observed: an intergranular zone caused by stress assisted anodic dissolution, and a transgranular cleavage zone, due to hydrogen absorption.