Zr-Nb合金包壳管氧化膜的微观结构  

Microstructure of Zr-Nb Alloy Cladding Oxide Flim

作　　者：王华才[1] 程焕林 郭丽娜[1] 汤琪[1] 韩华[1] WANG Huacai;CHENG Huanlin;GUO Lina;TANG Qi;HAN Hua(China Institute of Atomic Energy,Beijing 102413,China)

机构地区：[1]中国原子能科学研究院,北京102413

出　　处：《腐蚀与防护》2022年第7期67-73,116,共8页Corrosion & Protection

基　　金：中核集团青年英才基金(FY202307000520)。

摘　　要：针对某Zr-Nb系合金包壳管水侧腐蚀,通过光学显微镜、X射线衍射分析(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)等技术,研究了Zr-Nb合金包壳管氧化膜的微观结构。结果表明:腐蚀生成的氧化膜表面分布有不同取向的微裂纹,其中垂直裂纹可以为氧离子的扩散提供快速路径。TEM分析表明氧化膜主要由柱状和等轴状单斜相ZrO_(2)组成,基体/氧化膜界面附近等轴状单斜相ZrO_(2)的存在与裂纹、大晶粒尺寸和晶内孪晶密切相关,导致ZrO_(2)发生由四方相到单斜相的转变,由于残余应力导致的晶格膨胀,单斜相ZrO_(2)晶面间距增加了约0.4%。The microstructure of the oxide film of Zr-Nb alloy cladding was studied by optical microscopy,X-ray diffraction analysis(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM).The results showed that microcracks with different orientations were distributed on the surface of the oxide film of Zr-Nb alloy,including vertical and transverse cracks.The vertical cracks could provide a fast path for the diffusion of oxygen ions.TEM results showed that the oxide film was mainly composed of columnar and equiaxed monoclinic ZrO_(2),The existence of equiaxed monoclinic ZrO_(2)grains near the interface of zirconium alloy matrix/oxide film was closely related to cracks,large grain size and intragranular twinning.Due to the lattice expansion caused by residual stress,the interplanar spacing of monoclinic ZrO_(2)increased about 0.4%.

关 键 词：Zr-Nb合金 氧化膜 裂纹 晶体结构 

分 类 号：TL341[核科学技术—核技术及应用]