锆合金包壳和GH4169镍基合金的微动摩擦磨损性能研究

Fretting Friction Wear Behavior of Zircaloy and Ni-Based GH4169 Alloy

燃料棒在冷却剂流过时易受到扰动而发生微振动,导致在格架弹簧与包壳管接触点附近产生微动摩擦磨损,严重时会导致燃料棒破损,放射性产物泄漏,从而影响核电厂安全运行,因而需要对燃料包壳的微动摩擦磨损性能进行充分研究。本研究旨在比较分析2种牌号、2种状态的锆合金(Zr-4)和N36与格架材料GH4169镍基合金在不同环境条件下的微动摩擦磨损性能,分析载荷、循环次数、环境条件对其摩擦磨损性能的影响,并结合磨损表面的形貌、成分分析结果,揭示其微动摩擦磨损机理。研究结果表明,微动摩擦磨损时摩擦系数随载荷的增加呈线性增加趋势;相同条件下,Zr-4/Zr-4摩擦副组合的微动摩擦系数最大,GH4169/N36摩擦副组合的微动摩擦系数最小;预氧化对材料的微动摩擦系数影响显著,预氧化态样品的摩擦系数均高于非预氧化态的样品。

The fuel rod tubes are disturbed under the condition of micro-vibration when the coolant flow pasts the surface of the fuel rod tubes from the bottom to the top during the operation of nuclear reactors, which can cause the fretting wear at the contact area of the frame spring and the tube cladding, and thus radio-active products might be leaked out under certain serious conditions, which will result in the shutdown of nuclear reactors, influencing its safety. The fretting wear behavior of Zirconium alloy Zr-4 and N36 mated with Ni-based GH4169 alloy was investigated in this work. The worn surfaces were examined with scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) and 3 D Microscopy. The obtained results showed that the friction efficient increases with the load increasing, and the Zr-4/Zr-4 has the maximum friction efficient, while the GH4169/N36 has the lowest friction efficient. Meanwhile, the preliminary oxidation has great influence on the friction behavior, and the friction coefficient of the pre-oxidized samples is higher than that of the non-pre-oxidized.