脉冲电流作用下纯铁及RPV钢缺陷修复的正电子湮没研究  

Positron annihilation study on defect repair of pure iron and RPV steel under electropulsing treatment

作　　者：文海懿 全琪玮 杨炫烨 赵文增 张思敏 吴奕初[1] 刘向兵[2] WEN Haiyi;QUAN Qiwei;YANG Xuanye;ZHAO Wenzeng;ZHANG Simin;WU Yichu;LIU Xiangbing(School of Physics and Technology,Hubei Key Laboratory of Nuclear Solid State Physics,Wuhan University,Wuhan 430072,China;Suzhou Nuclear Power Research Institute,Suzhou 215004,China)

机构地区：[1]武汉大学物理科学与技术学院湖北省核固体物理重点实验室,武汉430072 [2]苏州热工研究院有限公司,苏州215004

出　　处：《核技术》2024年第8期15-22,共8页Nuclear Techniques

基　　金：国家自然科学基金(No.12275200,No.U23B2072);国家重点研发计划项目课题(No.2019YFA0210003,No.2021YFA1600903)资助~~。

摘　　要：为探究电脉冲处理(Electropulsing Treatment,EPT)对金属材料缺陷的修复作用,设计了一套电脉冲处理设备和与其配套的处理方法,并对电子辐照样品与拉伸样品等含有缺陷的金属材料样品进行电脉冲处理。利用正电子谱学对原子尺度缺陷的十分灵敏的特点,对电脉冲处理后样品进行正电子寿命谱学等研究,获得纯铁及反应堆压力容器(Reactor Pressure Vessel,RPV)钢辐照或形变产生的缺陷及通过电脉冲处理后的部分“修复”情况。结果表明:缺陷“修复”的效果既与样品初始状态有关,又与电脉冲处理参数有关,电脉冲处理样品的正电子平均寿命和维氏硬度变化趋势一致。正电子湮没作为新的无损检测方法有望给出脉冲电流作用下材料损伤或缺陷“修复”的判据,可方便、快速及高灵敏探测实际工况部件的缺陷状态。[Background]The defects generated during the working process of metal materials have a significant impact on their performance.For example,the radiation-induced embrittlement and hardening of reactor pressure vessel(RPV)steels are a factor of concern,which hinders the life extension of the RPV.Annealing treatment is applied to alleviating irradiation-induced precipitates and defects and recover RPV's mechanical properties in the past few decades to extend the in-service lifetime of the RPV.Unfortunately,this conventional method generally requires a high treatment temperature and long operation time,inevitably wasting considerable energy due to the huge size of the RPV.Recently,as a more convenient and energy-saving method,the repair of metal defects by electropulsing treatment(EPT)has been developed.[Purpose]This study aims to design and construct a device for EPT processing of samples,and investigate the repairs of defects in electron irradiated and deformed iron and RPV steel after EPT by using positron lifetime spectroscopy.[Methods]Electron irradiated pure iron and RPV steel samples were prepared and subjected to multi parameter EPT device developed in laboratory,and the changes in defects of the samples with EPT were characterized by positron lifetime spectroscopy.In addition,the mechanical properties of pure iron tensile samples were characterized by micro Vickers hardness,and the defect information was characterized by positron lifetime spectroscopy to explore the relationship between macroscopic properties and microstructure.[Results]The defects introduced by electron irradiation in pure iron and RPV steel samples gradually recover after EPT and exhibit similar patterns to annealing treatment.After stretching,the number of defects in pure iron samples increases,leading to an increase in Vickers hardness.EPT can restore defect and reduce Vickers hardness.[Conclusions]The defects generated by irradiation or deformation in pure iron and RPV steel can be partially repaired through EPT.The effect of defect rep

关 键 词：正电子湮没 脉冲电流 缺陷 修复 纯铁 

分 类 号：TL99[核科学技术—核技术及应用] TB303[一般工业技术—材料科学与工程]