Life Extension Potential Analysis of U₃Si₂-Al Fuel Plate Element

Plate-type fuel elements are a nuclear fuel design widely used in research reactors, test reactors, and some power reactors. The in-pile irradiation performance of plate-type fuel elements is a critical factor influencing reactor refueling cycles and operational duration. Numerical simulations based on the fully coupled thermo-mechanical method in ABAQUS were conducted to achieve interactive coupling among stress, temperature, and displacement, thereby simulating the thermo-mechanical behavior of plate-type fuel elements under in-pile irradiation conditions.The results indicate that burnup has minimal impact on the temperature field for dispersion-type fuel meat. As burnup increases, the Mises stress within the plastic regime flattens slightly and becomes lower than values observed at adjacent regions. Swelling rates and maximum cladding stresses were calculated for multiple burnup levels, demonstrating that plate-type fuel retains sufficient safety margins even at high burnup, confirming its potential for continued use. This study provides an effective analytical approach for extending the service life of U<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>Si<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>-Al plate-type fuel elements.