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Given the previously mentioned fact that the probability of component failure caused by PCI in pressurized water reactors is extremely low, the typical cases of component failure related to PCI in pressurized water reactors that are currently available in public are as follows: First, the PCI-related failure incident in the PWR1 reactor in the United States during its startup phase in the early 2000s. Background of the incident: At the beginning of the 2000s, this commercial pressurized water reactor experienced leaks in some IFBA (Integrated Fuel Burnable Absorber) fuel rods during cyclic startups and intermediate power restoration processes. Root cause conclusion: Analysis indicates that it is a \"defect-assisted PCI\"; the geometric characteristics of the missing surface area in the core block (MPS) lead to local stress concentration, which ultimately causes cracking and failure of the PCI-type cladding. II. Suspected PCI failure incident during the second cycle startup of Westinghouse pressurized water reactors. Background: Based on the operational experience of multiple Westinghouse pressurized water reactors in service, 9 potential or confirmed cases of PCI failure during the second cycle startup were identified. Analysis process: The relevant research team utilized a database of over 3,000 successfully operated Westinghouse pressurized water reactor fuel rods, and through the FALCON program, carried out comprehensive PCI stress calculations and failure analyses to determine the risk boundaries for PCI during such start-up transients. Additional note: Publicly available information shows that there are very few cases of large-scale, mass failures in pressurized water reactors caused directly by PCI; this failure mode is a low-probability event in such reactors, far less common than other causes of failure such as abrasion and corrosion.