Stoffersen Birgitte, Cooper Daniel John, Jellesen Morten Stendahl, Hald John
Seaborg Technologies, Titangade 11, 2200, Copenhagen, Denmark.
Section of Materials and Surface engineering, DTU Construct, Technical University of Denmark, 2800, Lyngby, Denmark.
Heliyon. 2024 May 31;10(11):e31995. doi: 10.1016/j.heliyon.2024.e31995. eCollection 2024 Jun 15.
The corrosion behavior of alloy Ni 201 in molten sodium hydroxide (NaOH) at 600 °C was investigated at varying basicity levels of the molten NaOH. The ability for Ni 201 to form passivating oxides was investigated after immersion tests varying from 70 to 340 h under atmospheres of argon and argon with different partial pressure of water. Morphology and thicknesses of the corrosion products were characterized by Scanning Electron Microscopy (SEM) and crystallography of the corrosion products by X-ray Diffraction (XRD). Dynamic polarizations were made to investigate the effects of basicity and electrochemical potential. The results showed that Ni 201 corroded at a reduced rate in molten acidic NaOH compared to neutral NaOH due to the formation of NiO. The oxide scales formed on Ni 201 in acidic NaOH were shown to grow non-parabolically and did not result in full corrosion protection as the oxide scales showed crack development over time.
研究了合金Ni 201在600°C的熔融氢氧化钠（NaOH）中，于不同碱度水平下的腐蚀行为。在氩气以及含有不同水分压的氩气气氛中，进行了70至340小时的浸泡试验后，研究了Ni 201形成钝化氧化物的能力。通过扫描电子显微镜（SEM）对腐蚀产物的形态和厚度进行了表征，并通过X射线衍射（XRD）对腐蚀产物的晶体结构进行了分析。进行了动态极化试验以研究碱度和电化学势的影响。结果表明，由于形成了NiO，与中性NaOH相比，Ni 201在熔融酸性NaOH中的腐蚀速率降低。在酸性NaOH中，Ni 201上形成的氧化皮显示出非抛物线型生长，并且随着时间的推移，氧化皮出现裂纹扩展，因此不能提供完全的腐蚀防护。
