On the problems of creating shells of fuel rods from zirconium alloys for tolerant fuel

Abstract

Three directions of the establishment of accident tolerant fuel cladding for light water reactors are actively exploring at present: 1) replacement zirconium alloy E110 for more corrosion-resistant material in accident operation conditions; 2) surface dispersion hardening or doping of the zirconium cladding of fuel element; 3) deposition a corrosion-resistant coating to the fuel cladding. The first direction requires significant and irreversible changes in fuel rod production technology and has long-term prospects. Conversely, the second direction suggest minimal changes in the fuel rod production technology, however, it has no significant effect on the high temperature oxidation kinetics of fuel claddings in steam. Using of a corrosion resistant coating results in a significant change in the high temperature oxidation kinetics of the zirconium alloy, (no transition to linear oxidation) that is related to maintaining the continuity of the oxide layer formed during oxidation. The issue provides a brief overview of the current state of research in the field of fuel, tolerant to the effects of coolant in emergency situations.