A Systematic Framework for Risk Assessment of Fusion Blanket: Addressing Manufacturing Defects, Accident Scenarios, and Radioactive Release

The breeder blanket, as a critical component in fusion reactors, undertakes three essential functions: tritium breeding, neutron shielding, and thermal energy conversion. Serving as the primary plasma‐facing component, it operates under extreme conditions—including sustained high temperatures, intense neutron irradiation fluxes, significant thermomechanical stresses induced by thermal cycling and plasma loading, and complex interactions with magnetic fields. These coupled operational challenges impose stringent reliability requirements, as blanket failure may lead to unplanned reactor shutdowns, structural integrity degradation, and heightened safety risks. This study establishes a systematic framework based on probabilistic risk assessment (PRA) to quantify breeder blanket failure risks and evaluate associated environmental radioactive contamination. The methodology comprises three key steps: (1) multidimensional failure mode analysis covering material degradation, manufacturing defects, assembly errors, environmental stressors, and accident scenarios; (2) quantitative risk annual frequency estimation via fault tree analyses to identify dominant failure pathways; and (3) proposing targeted mitigation strategies (e.g., advanced material selection, enhanced quality control, and real‐time monitoring) to improve blanket reliability and reduce accident probabilities. The proposed framework provides a comprehensive approach for failure risk quantification and preventive design, offering scientific support to enhance the safety and operational sustainability of fusion reactors.