Cr coating on Zr-based fuel tubes is a potential approach for the development of accident tolerant fuels (ATF). To settle the cracking behavior and quantitative evaluation of shear strength of Cr coating under different loading conditions, the average shear strength between Cr coating and zircaloy substrate has been estimated using a modified shear-lag model in this paper. Its key parameters are determined experimentally, and the tensile method has been used to research the cracking behavior of Cr coating under different strain rates. The results show that with the increase of strain rate, the interfacial shear strength increases because of the decrease of cracking spacing, while the shear strength changes erratically with the coating thickness increases. Furthermore, abundant two unequal-crack-spacings and few two equal-crack-spacings are observed which are perpendicular to the loading direction.

中文翻译：

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不同应变速率下锆合金燃料包壳 Cr 涂层的剪切强度和开裂行为

Zr 基燃料管上的 Cr 涂层是开发耐事故燃料 (ATF) 的一种潜在方法。为了解决Cr涂层在不同加载条件下的开裂行为和剪切强度的定量评价，本文采用改进的剪切滞后模型估算了Cr涂层与锆合金基体之间的平均剪切强度。通过实验确定了其关键参数，并采用拉伸法研究了Cr涂层在不同应变速率下的开裂行为。结果表明，随着应变速率的增加，界面剪切强度因裂纹间距的减小而增加，而剪切强度随涂层厚度的增加而变化不规律。此外，