Preliminary Investigation on Burst Behaviors of Zr-Based Cladding Under Simulated LOCA Conditions

Abstract The Fukushima accident exposed the shortcomings of zirconium-based fuel cladding in withstanding severe loss of coolant accidents (LOCA), thereby accelerating the development of accident-tolerant fuel (ATF). Over the past decade, extensive technical exploration has led to chromium (Cr) coated zirconium cladding emerging as the primary technological route slated for commercial application soon. In current study, the burst behaviors of zirconium-based claddings were systematically investigated under simulated LOCA conditions. The initial internal pressures ranged from 2–10MPa, and the heating rates were 14 °C/s and 28 °C/s. Although research on Cr-coated cladding is still ongoing, preliminary findings from the zirconium-based cladding analysis indicate that at a consistent heating rate, the burst time decreases with increasing internal pressure, and the burst temperature decreases accordingly. Conversely, at a constant initial internal pressure, the burst time decreases as the heating rate increases, but the burst temperature elevates.