The effect of oblique crack on stability and fracture properties of Cr-coated Zircaloy cladding

In this paper, fracture properties of Cr-coated Zircaloy cladding, which has initial oblique crack in the coating, have been investigated. The von Mises stress distribution caused by different modes of crack has been calculated. By comparing the stress intensity factor with the fracture toughness of material, the fracture mechanical behavior of Cr coating has been obtained. When the reactor is in normal opera-tion, conditions for crack propagation along the axial direction are very strict. However, if the crack prop -agates in the plane perpendicular to the axial direction, two types of cladding failure may occur: 1) coating spallation and 2) a crack channel connecting the cladding to the coolant. Conditions of occurrence of these two types have been analyzed. Meanwhile, a map of the relation between initial crack state and crack development trend is given. It can provide reference and guidance for the coating monitoring in real nuclear engineering. CO 2021 Elsevier Ltd. All rights reserved.

Automated summary

This paper investigates the fracture properties of Cr-coated Zircaloy cladding with initial oblique cracks, analyzing stress distribution, fracture mechanical behavior, and different types of cladding failure. The study provides a map of the relation between initial crack state and crack development trend, offering reference and guidance for coating monitoring in nuclear engineering.