Microstructural Processes in Thermal Creep of Zirconium Nuclear Fuel Cladding Tubes

Abstract:

The origin of the thermal creep of zirconium cladding tubes in all light water reactors is still the subject of deep confusion and intricate controversies. The reason for this inconvenient situation is obviously that microstructural processes in thermal creep remain poorly understood and this is due to the relatively small number of studies that have been carried out. In this study uniaxial creep tests in tension of zirconium alloy cladding tubes in the as-received and pre-hydrided states are followed by metallographic analysis of the as-received and crept specimens by light microscopy and SEM to explain the observed high-temperature creep behavior of the tubes.

• Periodical: Materials Science Forum (Volume 1166)
• Pages: 3-8
• DOI: https://doi.org/10.4028/p-XOGk9z
• Online since: November 2025
• Authors: Petr Král*, Květa Kuchařová, Marie Kvapilová, Jiří Dvořák, Jakub Krejčí, Václav Sklenička
• Keywords: Hydridation, LOCA Accident, Microstructural Analyses, Nuclear Fuel Cladding Tube, Oxidation, Thermal Creep, Zr1%Nb Alloy

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