FeCrAl/ZrNbCu复合管包壳高温蒸气氧化行为研究

A Study Of High Temperature Steam Oxidation behavior of FeCrAl/ZrNbCu Dual Layer Tube Cladding

摘要:

FeCrAl/ZrNbCu复合管兼顾了Zr合金和FeCrAl合金的优点，是事故容错燃料包壳候选材料之一。本文研究了FeCrAl/ZrNbCu复合管蒸气氧化行为，结果表明，外层FeCrAl材料具有优异的抗蒸气氧化性能，有效保护了内层Zr合金管。氧化产物分析表明，FeCrAl合金氧化膜呈凹凸状，氧化产物为Fe2O3、FeCr2O4、Cr2O3和Al2O3；ZrNbCu合金氧化膜垂直于表面生长，氧化产物为ZrO2和Nb2O5；在1000℃氧化时复合管界面没有明显元素扩散；在1100℃和1200℃氧化后界面发生明显元素扩散。复合管外侧到内侧分别为FeCrAl氧化膜、FeCrAl合金、FeCrAl-ZrNbCr扩散层、ZrNbCu合金、ZrNbCu氧化膜；界面结合方式由机械结合转变为冶金结合。

Abstract:

FeCrAl / ZrNbCu dual layer tube is one of the candidate materials for accident tolerant fuel cladding, which takes the advantages of ZrNbCu alloy and FeCrAl alloy into account. In this paper, the high-temperature steam oxidation behavior of FeCrAl /ZrNbCu dual layer tube is studied. The results show that the outer layer FeCrAl material has excellent high temperature steam oxidation resistance, and the inner ZrNbCu alloy layer can be effectively protected by FeCrAl alloy. The concave and convex morphology of oxide film of FeCrAl alloy is formed, and the oxidation products are Fe2O3, FeCr2O4, Cr2O3 and Al2O3. The oxide film of ZrNbCu alloy grows perpendicular to the surface, and the oxidation products are ZrO2 and Nb2O5. Element diffusion at the interface of the dual layer tube can not be found when it is oxidized at 1000 ℃; there is obvious element diffusion at the interface when it is oxidized at 1100 ℃ and 1200 ℃. From the outer side to the inner side of the dual layer tube, FeCrAl oxide film, FeCrAl alloy, FeCrAl-ZrNbCu diffusion layer, ZrNbCu alloy and ZrNbCu oxide film are formed; the original mechanical bonding transforms to metallurgical bonding when the temperature is above 1100 ℃.