Relative motion between the fuel rods and fuel assembly spacer grids can lead to excessive fuel rod wear and, in some cases, to fuel rod failure. Based on industry data, such grid-to-rod-fretting is a significant cause of fuel failures in U.S. pressurized water reactor power plants. Kanthal advanced powder metallurgy technology or APMT, an FeCrAl steel alloy, and a braided SiC fiber, Chemical Vapor Infiltration SiC matrix (SiC/SiC) cladding by General Atomics are possible alternatives to conventional fuel cladding in a nuclear reactor due to their favorable performance under accident conditions. Tests were performed to examine the reliability of the cladding candidates and a conventional cladding, Zircaloy-4, under dry fretting conditions at elevated temperature. The contact was simulated with a rectangular and a cylindrical specimen over a line contact area. Confocal scanning laser microscopy was used to obtain a 3D map of the surface, which was in turn used for wear and work rate calculations on the samples. The wear rate coefficient was used as a measure of the performance and wear under fretting. Additionally, Energy Dispersive Spectroscopy was performed to qualitatively describe the microchemical changes the material undergoes during fretting. While APMT steel and SiC/SiC can perform favorably in loss of coolant accident scenarios, they also need to perform well when compared to Zircaloy-4 with respect to fretting wear. Wear coefficient measurements showed that APMT steel performs favorably in comparison to Zircaloy-4 with respect to fretting wear.

燃料棒和燃料组件隔板之间的相对运动会导致燃料棒过度磨损，并在某些情况下导致燃料棒故障。根据行业数据，这种网格到杆的微动是导致美国压水堆发电站燃料故障的重要原因。Kanthal先进的粉末冶金技术或APMT，FeCrAl钢合金和编织SiC纤维，通用原子化学公司的化学气相渗透SiC基体（SiC / SiC）包层是核反应堆中常规燃料包层的可能替代品，因为它们在低温下具有良好的性能事故情况。进行了测试，以在高温干式微动条件下检查候选熔覆层和常规熔覆层Zircaloy-4的可靠性。用矩形和圆柱形样品在线接触区域上模拟了接触。共聚焦扫描激光显微镜用于获得表面的3D图，然后将其用于样品的磨损和工作率计算。磨损率系数用作微动性能和磨损的量度。此外，进行了能量色散光谱学，以定性描述材料在微动过程中发生的微化学变化。尽管APMT钢和SiC / SiC在损失冷却剂事故的情况下表现良好，但与Zircaloy-4相比，它们在微动磨损方面也需要表现良好。磨损系数测量表明，在微动磨损方面，APMT钢的性能优于Zircaloy-4。共聚焦扫描激光显微镜用于获得表面的3D图，然后将其用于样品的磨损和工作率计算。磨损率系数用作微动性能和磨损的量度。此外，进行了能量色散光谱学，以定性描述材料在微动过程中发生的微化学变化。尽管APMT钢和SiC / SiC在损失冷却剂事故的情况下表现良好，但与Zircaloy-4相比，它们在微动磨损方面也需要表现良好。磨损系数测量表明，在微动磨损方面，APMT钢的性能优于Zircaloy-4。使用共聚焦扫描激光显微镜获得表面的3D图，然后将其用于样品的磨损和工作率计算。磨损率系数用作微动性能和磨损的量度。此外，进行了能量色散光谱学，以定性描述材料在微动过程中发生的微化学变化。尽管APMT钢和SiC / SiC在损失冷却剂事故的情况下表现良好，但与Zircaloy-4相比，它们在微动磨损方面也需要表现良好。磨损系数测量表明，在微动磨损方面，APMT钢的性能优于Zircaloy-4。磨损率系数用作微动性能和磨损的量度。此外，进行了能量色散光谱学，以定性描述材料在微动过程中发生的微化学变化。尽管APMT钢和SiC / SiC在损失冷却剂事故的情况下表现良好，但与Zircaloy-4相比，它们在微动磨损方面也需要表现良好。磨损系数测量表明，在微动磨损方面，APMT钢的性能优于Zircaloy-4。磨损率系数用作微动性能和磨损的量度。此外，进行了能量色散光谱学，以定性描述材料在微动过程中发生的微化学变化。尽管APMT钢和SiC / SiC在损失冷却剂事故的情况下表现良好，但与Zircaloy-4相比，它们在微动磨损方面也需要表现良好。磨损系数测量表明，在微动磨损方面，APMT钢的性能优于Zircaloy-4。与Zircaloy-4相比，它们在微动磨损方面也需要表现良好。磨损系数测量表明，在微动磨损方面，APMT钢的性能优于Zircaloy-4。与Zircaloy-4相比，它们在微动磨损方面也需要表现良好。磨损系数测量表明，在微动磨损方面，APMT钢的性能优于Zircaloy-4。