Internal hydriding has been the most persistent cause of defects in water reactor fuel pins. This paper discusses the mechanism of heterogeneous internal hydriding, the effect of bore surface condition, the critical amount of hydrogen and criteria by which it may be specified. It also comments on production methods for achieving low hydrogen content. Other factors which contribute together with internal hydriding to the initiation of a leak path through the cladding are discussed. Attack by other impurities, including fission products is considered, and the attack of stressed zirconium alloys iodine is shown to be capable of producing major cracks. The mechanism of this process is not fully understood, nor are the effect of irradiation and the physical condition of the cladding, but recommendations are made on measures to minimize its incidence. © 1975.
Pickman, D. O. (1975). Internal cladding corrosion effects. Nuclear Engineering and Design, 33(2), 141–154. https://doi.org/10.1016/0029-5493(75)90019-9