90Nb-10Zr合金在500℃过热蒸气中的腐蚀行为  

Corrosion Behavior of 90Nb-10Zr Alloy in 500℃Super-Heated Steam

作　　者：吴悦 陈兵[1] 林晓冬 胡丽娟[1] 梁雪[2] 彭剑超[2] 姚美意[1] 周邦新[1] Wu Yue;Chen Bing;Lin Xiaodong;Hu Lijuan;Liang Xue;Peng Jianchao;Yao Meiyi;Zhou Bangxin(Institute of Materials,Shanghai University,Shanghai 200072,China;Laboratory for Microstructures,Shanghai University,Shanghai 200444,China)

机构地区：[1]上海大学材料研究所,上海200072 [2]上海大学微结构重点实验室,上海200444

出　　处：《稀有金属材料与工程》2021年第12期4437-4444,共8页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51871141,51471102)。

摘　　要：为深入研究锆合金中β-Nb第二相粒子在500℃、10.3 MPa过热蒸气中的腐蚀行为,利用真空非自耗电弧炉熔炼了β-Nb第二相合金90Nb-10Zr,在静态高压釜中进行500℃、10.3 MPa过热蒸气腐蚀试验,利用XRD、SEM和TEM分析了氧化膜的显微组织。结果表明,90Nb-10Zr合金腐蚀1 h时,外表面与腐蚀介质直接接触被氧化成单斜结构的Nb_(2)O_(2)。腐蚀7 h时,由于腐蚀介质中的氧化性物质需向内扩散才会发生进一步腐蚀,90Nb-10Zr合金表面的氧化膜为双层结构:外层为稳态的单斜结构的Nb_(2)O_(2)(m-Nb_(2)O_(2)),内层为亚稳态的四方结构的Nb_(2)O_(5)(t-Nb_(2)O_(5));在本研究中没有检测到Zr单独的氧化物。这一氧化过程可以合理解释含Nb锆合金在过热蒸气中的腐蚀行为与Nb含量的关系。In order to further study the corrosion behavior ofβ-Nb second phase particles(SPPs)in zirconium alloys,a bulk 90Nb-10Zr alloy was prepared by vacuum non-consumable arc furnace based on the chemical composition and crystal structure ofβ-Nb SPPs.The 90Nb-10Zr alloy was corroded in super-heated steam at 500℃and 10.3 MPa in a static autoclave for 1 and 7 h.The microstructure of the oxide film formed on the alloy was characterized by XRD,SEM and TEM.The results show that the monoclinic Nb_(2)O_(2)is formed directly when 90Nb-10Zr alloy is corroded for 1 h,because the corrosion medium is directly contacted with the outer surface of the alloy.When 90Nb-10Zr alloy is corroded for 7 h,the oxide film on the alloy is double-layer structure:the outer layer is m-Nb_(2)O_(2)and the inner layer is t-Nb_(2)O_(5)since the occurrence of further corrosion requires the internal diffusion of the oxidizing substances in the corrosion medium.No single oxide of Zr is detected in this study.This oxidation process can reasonably explain the relationship between the corrosion behavior of Nb-containing zirconium alloy in super-heated steam and the Nb content.

关 键 词：锆合金 90Nb-10Zr合金 腐蚀 氧化膜 显微组织 

分 类 号：TG146.416[一般工业技术—材料科学与工程]