The harsh conditions in the reactor affect the thermal and mechanical performance of the fuel plate heavily. Some in-pile behaviors, like fission-induced swelling, can cause a large deformation of fuel plate at very high burnup, which may even disturb the flow of coolant. In this research, the emphasis is put on the thermal expansion, fission-induced swelling, interaction layer (IL) growth, creep of the fuel meat, and plasticity of the cladding for the U₃Si₂/Al dispersion fuel plate. A detailed model of the fuel meat swelling is developed. Taking these in-pile behaviors into consideration, the three-dimensional large deformation incremental constitutive relations and stress update algorithms have been developed to study its thermal-mechanical performance under normal conditions using Abaqus. Results have shown that IL can effectively decrease the thermal conductivity of fuel meat. The high Mises stress region mainly locates at the interface between fuel meat and cladding, especially around the side edge of the interface. With irradiation time increasing, the stress in the fuel plate gets larger resulting from the growth of fuel meat swelling but then decreases under the effect of creep deformation. For the cladding, plasticity deformation does not occur within the irradiation time.

反应堆中的恶劣条件严重影响了燃料板的热性能和机械性能。一些堆内行为，如裂变引起的膨胀，会在非常高的燃耗情况下导致燃料板的大变形，甚至可能干扰冷却剂的流动。在这项研究中，重点放在 U ₃ Si ₂的热膨胀、裂变引起的膨胀、相互作用层 (IL) 生长、燃料肉的蠕变和包壳的塑性上。/Al 分散燃料板。开发了燃料肉膨胀的详细模型。考虑到这些堆内行为，开发了三维大变形增量本构关系和应力更新算法，以使用 Abaqus 研究其在正常条件下的热力学性能。结果表明，IL可以有效降低燃料肉的导热系数。高米塞斯应力区主要位于燃料肉与包壳的界面处，尤其是界面侧边附近。随着辐照时间的增加，燃料板中的应力因燃料肉膨胀的增长而变大，然后在蠕变变形的作用下减小。对于熔覆层，在辐照时间内不会发生塑性变形。