Xe离子辐照对Zr-1Nb合金表面形貌及电化学腐蚀特性的影响  

Influence of Xe Ion Irradiation on Surface Morphology and Electrochemical Corrosion Behavior of Zr-1Nb Alloy

作　　者：王荣山[1,2] 贾兴娜 周茜 张晏玮 柏广海[1,2] 徐驰 薛文斌[3,4] Wang Rongshan;Jia Xingna;Zhou Qian;Zhang Yanwei;Bai Guanghai;Xu Chi;Xue Wenbin(Suzhou Nuclear Power Research Institute Co.,Ltd,Suzhou 215004,China;National Engineering Research Center for Nuclear Power Plant Safety&Reliability,Suzhou 215004,China;Key Laboratory of Beam Technology of Ministry of Education,College of Nuclear Science and Technology,Beijing Normal University,Beijing 100875,China;Innovation Center of Nuclear Materials for National Defense Industry,Beijing 102413,China)

机构地区：[1]苏州热工研究院有限公司,江苏苏州215004 [2]国家核电厂安全及可靠性工程技术研究中心,江苏苏州215004 [3]北京师范大学核科学与技术学院射线束技术教育部重点实验室,北京100875 [4]国防科技工业核材料创新中心,北京102413

出　　处：《稀有金属材料与工程》2024年第10期2906-2912,共7页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(12005018,12105017);国防科技工业核材料创新中心(ICNM-2022-YZ-02,ICNM-2020-YZ-04)。

摘　　要：锆合金包壳在反应堆环境下受到辐照与腐蚀的协同作用。本工作使用6.37 MeV Xe离子辐照Zr-1Nb合金,评估了常温0.5mol/LLiOH水环境中辐照前后Zr-1Nb合金的电化学腐蚀特性,并测量了辐照前后Zr-1Nb合金的显微硬度和表面形貌、物相组成。经过Xe离子辐照后,Zr-1Nb合金表面出现了离子剥蚀形成的凹凸起伏,硬度和表面粗糙度随辐照剂量增加而增加。0.5dpa剂量辐照后样品的腐蚀电流密度相比于未辐照样品增加约18倍,2.7dpa剂量样品则增加约82倍。同时,辐照后样品的腐蚀电位降低,极化电阻显著减小。此外,辐照后Zr-1Nb合金样品低频阻抗降低,容抗弧半径也随辐照剂量增加而减小。极化曲线和电化学阻抗测量结果表明,离子辐照增强了Zr-1Nb合金的腐蚀倾向,其耐腐蚀性能随辐照剂量增加而降低。电化学腐蚀测试后,Zr-1Nb合金表面出现了板条形组织,且离子辐照后样品该板条形组织更加细小。Zr-1Nb合金辐照样品耐腐蚀性能下降主要是合金基体的辐照损伤导致的结果。Zirconium alloy cladding suffers from the synergetic effect of irradiation and corrosion degradations in reactor environment.In order to evaluate the effect of irradiation on the electrochemical corrosion behavior of the Zr-1Nb alloy before and after irradiation in 0.5 mol/L LiOH solution at room temperature,the alloy was irradiated with 6.37 MeV Xe ions.The microhardness,surface morphology and phase composition of Zr-1Nb alloy before and after irradiation were measured.After the Xe ion irradiation,the surface of Zr-1Nb alloy has a bump formed by ion denudation.The microhardness and surface roughness are increased with the increase in irradiation dose.The polarization current density of the 0.5 dpa dose irradiated sample is increased by 18 times than that of the unirradiated sample,while it is about 82 times higher of the 2.7 dpa irradiated sample,compared with the unirradiated sample.After the ion irradiation tests,the polarization potential and polarization resistance of the samples decrease significantly.In addition,the lower-frequency impedance is decreased,and the curvature radius of the capacitance curve is also decreased with the increase in irradiation dose.The polarization curves and EIS results show that the ion irradiation increases the corrosion tendency of the Zr-1Nb alloy,and its corrosion resistance is decreased with the increase in irradiation dose.After electrochemical corrosion test,the surface of Zr-1Nb alloy has a strip structure,and the strip is finer after ion irradiation.The reduced corrosion resistance after the ion irradiation tests is considered to be mainly caused by the irradiation induced damage on the alloy matrix.

关 键 词：锆合金 离子辐照 腐蚀 电化学阻抗谱 极化曲线 

分 类 号：TG146.414[一般工业技术—材料科学与工程] TL341[金属学及工艺—金属材料]