核技术
覈技術
핵기술
NUCLEAR TECHNIQUES
2015年
7期
070601-1-070601-6
,共1页
邱杰%邹杨%李志军%徐洪杰
邱傑%鄒楊%李誌軍%徐洪傑
구걸%추양%리지군%서홍걸
镍基合金%FLiNaK盐%腐蚀%Cr
鎳基閤金%FLiNaK鹽%腐蝕%Cr
얼기합금%FLiNaK염%부식%Cr
Nickel-based alloys%FLiNaK salt%Corrosion%Cr
为探究不同Cr含量的镍基合金在熔盐环境中的腐蚀行为，在700°C的FLiNaK (LiF-NaF-KF：46.5-11.5-42 mol%)盐中对Hastelloy B-2、Haynes 242、Hastelloy S、GH3030和Hastelloy X五种不同Cr含量的镍基高温合金进行了400 h的腐蚀实验。利用扫描电子显微镜(Scanning Electron Microscope, SEM)和电子探针(Electron Probe Microanalysis, EPMA)对腐蚀后样品进行表征，结合样品失重，对不同Cr含量合金的腐蚀规律进行归纳分析。结果表明，合金的耐腐蚀性能受其Cr含量的影响较大，低Cr合金(Hastelloy B-2和Haynes 242)具有较好的耐熔盐腐蚀性能，高Cr合金耐熔盐腐蚀性能较差，当合金中Cr含量大于20%时(GH3030和Hastelloy X)，腐蚀急剧增加，合金表面出现明显的贫Cr层，合金不适合在熔盐环境中应用。
為探究不同Cr含量的鎳基閤金在鎔鹽環境中的腐蝕行為，在700°C的FLiNaK (LiF-NaF-KF：46.5-11.5-42 mol%)鹽中對Hastelloy B-2、Haynes 242、Hastelloy S、GH3030和Hastelloy X五種不同Cr含量的鎳基高溫閤金進行瞭400 h的腐蝕實驗。利用掃描電子顯微鏡(Scanning Electron Microscope, SEM)和電子探針(Electron Probe Microanalysis, EPMA)對腐蝕後樣品進行錶徵，結閤樣品失重，對不同Cr含量閤金的腐蝕規律進行歸納分析。結果錶明，閤金的耐腐蝕性能受其Cr含量的影響較大，低Cr閤金(Hastelloy B-2和Haynes 242)具有較好的耐鎔鹽腐蝕性能，高Cr閤金耐鎔鹽腐蝕性能較差，噹閤金中Cr含量大于20%時(GH3030和Hastelloy X)，腐蝕急劇增加，閤金錶麵齣現明顯的貧Cr層，閤金不適閤在鎔鹽環境中應用。
위탐구불동Cr함량적얼기합금재용염배경중적부식행위，재700°C적FLiNaK (LiF-NaF-KF：46.5-11.5-42 mol%)염중대Hastelloy B-2、Haynes 242、Hastelloy S、GH3030화Hastelloy X오충불동Cr함량적얼기고온합금진행료400 h적부식실험。이용소묘전자현미경(Scanning Electron Microscope, SEM)화전자탐침(Electron Probe Microanalysis, EPMA)대부식후양품진행표정，결합양품실중，대불동Cr함량합금적부식규률진행귀납분석。결과표명，합금적내부식성능수기Cr함량적영향교대，저Cr합금(Hastelloy B-2화Haynes 242)구유교호적내용염부식성능，고Cr합금내용염부식성능교차，당합금중Cr함량대우20%시(GH3030화Hastelloy X)，부식급극증가，합금표면출현명현적빈Cr층，합금불괄합재용염배경중응용。
Background:Corrosion of the structural materials of Molten Salt Reactor (MSR) has been recognized as a challenge that prevents the MSR from long term operation. Oak Ridge National Laboratory (ORNL) has revealed that corrosion occurs predominantly through dealloying of Cr from the candidate nickel-based high temperature alloys. Therefore, a systematic study on the corrosion characteristics of candidate structural materials is needed to ensure their applications in MSR.Purpose:The present work is to evaluate the corrosion behaviors of some nickel-based alloys with different Cr content as well as to supply more corrosion data of materials in molten fluoride salts for reliable selection of structural materials.Methods:Static corrosion tests of five kinds of nickel-based high temperature alloys (Hastelloy B-2, Haynes 242, Hastelloy S, GH 3030 and Hastelloy X) were performed in purified molten FLiNaK salt at 700 °C for 400 h. The microstructural morphology and chemical composition of the samples were examined by Scanning Electron Microscope (SEM) and Electron Probe Microanalysis (EPMA).Results: Hastelloy B-2 and Haynes 242 with low Cr content exhibited better corrosion resistance, while the high Cr-content alloys, GH 3030 and Hastelloy X, exhibited severe corrosion after the corrosion tests. Conclusion:It was found that the corrosion was correlated with the original Cr-content of the alloys, and the weight-loss/area due to corrosion increased with the Cr-content of alloys. When the Cr content of alloys is higher than 20 wt.%, these alloys would suffer severe corrosion in molten fluoride salt environments.
