The effects of different fuel cladding materials on neutronic behavior and fuel depletion performance in the VVER-1200 reactor

This study investigates the impact of different fuel cladding materials on the performance and safety of VVER-1200 reactors using the Serpent 2 Monte Carlo code. Cladding materials evaluated include Zircaloy, 304SS, 310SS, FeCrAl, APMT, TiC, ZrC, and SiC. Key parameters assessed are fuel performance, neutronic behavior, infinite multiplication factor (kinf), and radioactive fission product levels. Results indicate that Zircaloy, ZrC, and SiC claddings retain criticality longer (kinf > 1) with favorable neutron flux and fission neutron production. TiC, however, loses criticality early and generates high neutron poisons and fission products. Steel alloys (304SS, 310SS), APMT, and FeCrAl demonstrate moderate performance affecting reactor criticality and neutron flux. Overall, Zircaloy is identified as the most effective cladding, balancing criticality, minimizing plutonium buildup, and reducing radioactive fission products, with ZrC and SiC as close competitors.