He泡对镍基合金腐蚀性能的影响  

The effect of He bubbles on the corrosion properties of nickel-based alloy in molten salt environment

作　　者：雷冠虹 杨斯达[3] 刘仁多[1] 李健健[1] 黄庆[1] 李诚[1] 黄鹤飞[1] 闫隆[1] LEI Guanhong;YANG Sida;LIU Renduo;LI Jianjian;HUANG Qing;LI Cheng;HUANG Hefei;YAN Long(Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China;University of Chinese Academy of Sciences, Beijing 100049, China;Shanghai Spaceflight Precision Machinery Institute, Shanghai 201600, China)

机构地区：[1]中国科学院上海应用物理研究所,上海201800 [2]中国科学院大学,北京100049 [3]上海航天精密机械研究所,上海201600

出　　处：《核技术》2019年第4期79-85,共7页Nuclear Techniques

基　　金：国家自然科学基金(No.11805256;No.11805261)资助~~

摘　　要：为了明确辐照对熔盐环境中合金腐蚀性能的影响,采用1.2 MeV的He离子对镍基UNS N10003合金进行了剂量为5×1015ions?cm-2和5×1016ions?cm-2的辐照实验,并将未辐照和辐照后的合金置于650℃的FLiNaK熔盐中进行200 h的腐蚀实验。采用扫描电子显微镜和透射电子显微镜对合金的表面形貌、元素分布及微观结构进行了分析。结果表明:低剂量下辐照未发现对合金腐蚀有明显的影响;高剂量下辐照后,合金中产生了He泡;在熔盐中腐蚀后,合金表面出现孔洞且Cr元素大量流失。利用纳米压痕技术对高剂量下辐照的合金在熔盐环境中的硬度演化行为进行了研究。结果显示:辐照后的合金硬度为4.12 GPa,腐蚀后的合金硬度为2.65 GPa,辐照腐蚀后的合金硬度为3.16 GPa,是辐照和腐蚀综合作用的结果。[Background] UNS N10003 alloy is considered to be the primary option of metal structural materials for the molten salt reactor (MSR). It will be affected by the extreme environments, i.e. high temperature, high neutron doses and corrosive coolant during the operation of MSR. Considering that the safe operation of MSR will mainly depends on the service performance of structural alloys, it is necessary to evaluate the performance of such kind of alloys in the complicated environments.[Purpose] This study aims at understanding the effect of He bubbles on the corrosion properties of UNS N10003 alloy in molten salt environment.[Methods] First of all, the 1.2 MeV high temperature He ion irradiation was performed on the UNS N10003 alloy at 650℃. The irradiation fluence was set up to 5×10^15ions·cm^-2 and 5×10^16ions·cm^-2 respectively. Then, samples were immersed in a dry high-purity graphite crucible filled with 200 g FLiNaK salts and heated to 650℃ for 200 h. Finally, scanning electron microscopy (SEM)and transmission electron microscope (TEM) were employed to investigate the surface morphology, the distribution of elements and the microstructure, respectively. Nano-indentation technique was used to obtain the hardness.[Results] At the dose of 5×10^15ions·cm^-2, there was not obvious difference in the surface morphology and distribution of element distribution of the corroded alloy with and without irradiation. While for the corroded alloy pre-irradiated with He ions at the dose of 5×10^16ions·cm^-2, large amount of holes were observed on the surface and the loss of Cr element was found from the bulk to the surface, which can be ascribed to the He bubbles formation. The hardness of irradiated alloy, corroded alloy, and corroded alloy pre-irradiated was 4.12GPa, 2.65GPa and 3.16GPa, respectively.[Conclusion] He bubbles formation play an important role on increasing the corrosion of UNS N10003 alloy. The hardness of irradiated and corroded alloy is lower than the irradiated alloy, and higher than of the corr

关 键 词：镍基合金 离子辐照 熔盐腐蚀 He泡 

分 类 号：TL341[核科学技术—核技术及应用]