鐵基金屬材料於超臨界水環境下之腐蝕行為研究

The Corrosion Behavior of Iron-Based Material in Supercritical Water Environments

陳亮璇(Liang-Hsuan Chen) ； 葉宗洸(Tsung-Kuang Yeh) ； 王美雅(Mei-Ya Wang)

《防蝕工程》 36卷2期 (2022/06) Pp. 12-22

https://doi.org/10.6376/JCCE.202206_36(2).0002

摘要

本實驗選用兩種鐵基金屬材料，分別為304H以及T92，暴露於超臨界水環境中檢測其耐腐蝕性與氧化行為，觀察其是否適合應用於超臨界水反應器中。將此二種合金試片置於25 MPa、650℃、溶氫濃度1 ppm及常溫常壓下的過飽和溶氧濃度之超臨界水環境下進行腐蝕試驗，實驗時間持續至1500小時。分析項目包括試片的質量變化，並使用掃描式電子顯微鏡（SEM）觀察氧化物形貌以及X射線能量散布分析儀（EDS）判定氧化物的組成成分。在25 MPa、650℃的超臨界水環境下，T92於兩種不同水化學環境下的氧化物形貌以及內外氧化層都較304H較為均勻且緻密，且304H之重量變化於溶氫及飽和溶氧水環境下皆有減少的趨勢，可以由此推測T92的抗腐蝕能力較304H優秀。

關鍵字

超臨界水環境 ； 鐵基金屬

並列摘要

In this experiment, two iron-based materials were selected, including T92 and 304H, to test in supercritical water environment and investigate their corrosion resistance and oxidizing behavior. Samples were exposed to a high-purity water environment with dissolved hydrogen (DH) concentration of 1 ppm and dissolved oxygen (DO) concentration over 19 ppm, respectively. The testing temperature was 650 ℃, the pressure was 25 MPa and the test duration varied from 500 to 1500 hours. After the corrosion tests, the mass change of specimens was measured with microbalance, and the morphology was observed by scanning electron microscopy (SEM). The composition of the oxide was analyzed with energy-dispersive X-ray spectroscopy (EDX) and the crystal structure of the oxide was characterized by Raman Spectrometer. Moreover, cross-sectional analysis was used to measure the thickness of the oxide films. From the results of mass change and cross-sectional analysis, the T92 samples showed better corrosion resistance than the 304H samples in all conditions.

並列關鍵字

Supercritical Water Environment ； Iron-Based Material

參考文獻

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