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• The design of the Core Assembly Deformation Test Facility was described in detail. • The conditions of assembly bending and thermal bowing tests were introduced briefly. • The heating and measurement technologies and the layout of sensors were introduced. China Demonstration Fast Reactor (CFR600) is under construction, and the Sub-assembly Deformation Analysis Program (SDAP) developed by China Institute of Atomic Energy is used to optimize the core design and operation management of CFR600. The Core Assembly Deformation Test Facility (CADTF), designed and built by Xi'an Jiaotong University, was selected to carry out a series of assembly bending and thermal bowing tests to provide validation problems for the SDAP. The specimen assembly was specially designed for better non-intrusive optical temperature measurement of the inner wrapper tube. The automatic heating control method and a lot of new measurement technology were applied into the tests to gain abundant and accurate test data. [ABSTRACT FROM AUTHOR]

• Behavior of Cr-coated clad under integral LOCA test is simulated in FEA. • Current burst criteria for Zircaloy is ineffective to capture Cr-coated concept. • New overstress and plasticity instability criteria for the Cr coating are proposed. • Coating thickness is found to be numerically insensitive to burst temperature. Chromium (Cr) coated cladding is one of the most promising accident-tolerant fuels for pressurized water reactors. The behavior of Cr-coated cladding under the accident conditions is crucial to quantify its implication on safety, licensing and economics. This work focuses on the modeling of the burst behavior of Cr-coated cladding under Loss of Coolant Accidents (LOCAs). For this purpose, the material properties and behavior models of Zircaloy and chromium have been studied and implemented into the ABAQUS. Then the ABAQUS models are compared against several burst tests done by Korea Atomic Energy Research Institute (KAERI) and Électricité de France (EDF). During the comparison process, different high temperature creep models, zircaloy cladding burst criteria and coating thicknesses are adopted to investigate the thermo-mechanical performance and burst behavior of Cr-coated claddings under LOCA. Based on the comparative computational analysis, 100% and 85% Cr fracture strength and the strain rate of 0.23 /s and 0.07 /s are proposed as a new overstress burst criterion for coated cladding under a heating rate from 5 K/s and 10 K/s. The effect of coating thickness on the proposed criteria and the ballooning behavior of the coated cladding was predicted to be insignificant. The proposed criteria are beneficial for better understanding of the coated clad burst phenomena and the best estimation of coated clad performance under LOCA scenarios. [ABSTRACT FROM AUTHOR]