Long term corrosion of Cr-Mo steels in superheated steam at 482 and 538 C
Long term corrosion of Cr-Mo steels in superheated steam at 482 and 538 C
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Cr-Mo钢在482和538℃过热蒸汽中的长期腐蚀
DOI：
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发表时间：
1982
期刊：
影响因子：
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通讯作者：
W. A. Maxwell
中科院分区：
文献类型：
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作者：
J. C. Griess;J. H. Devan;W. A. Maxwell
研究了几种Cr-Mo铁素体钢在电厂过热蒸汽中的腐蚀行为。测试在482和538 C（900和1000 F）下在单程回路中进行，时间长达28，000小时（3.2年）。铬浓度范围从2.0到11.4%，和腐蚀的表面处理的效果进行了研究。在482 ℃下，许多试样中只有一个显示出剥落的迹象，但在538 ℃下，大多数材料的至少一些试样上发生剥落;例外是铬含量最高的合金（Sandvik HT-9），硅含量最高的9 Cr-1 Mo钢和Sumitomo 9 Cr-2 Mo钢，该钢仅进行了19，000小时的试验。抛物线氧化动力学充分描述了腐蚀过程的第一年左右，之后的腐蚀速率是恒定的，低于预测从外推的渗透与时间曲线的初始部分。铬浓度在2%和9%之间时，腐蚀行为与铬含量无关，Sandvik HT-9的腐蚀略低。腐蚀几乎与表面处理无关，但在两种情况下，在蒸汽暴露之前表面上存在的氧化皮似乎延缓了蒸汽中的氧化。«少
The corrosion of several Cr-Mo ferritic steels was investigated in superheated steam at an operating power plant. Tests were conducted at 482 and 538 C (900 and 1000 F) in a once-through loop for times up to 28,000 hours (3.2 years). Chromium concentrations ranged from 2.0 to 11.4%, and the effect of surface preparation on corrosion was investigated. Only one of many specimens showed evidence of exfoliation at 482 C, but at 538 C, exfoliation occurred on at least some of the specimens of most materials; the exceptions were the alloy with the highest chromium content (Sandvik HT-9), one heat of 9 Cr-1 Mo steel with the highest silicon content, and Sumitomo 9 Cr-2 Mo steel, which was in test for only 19,000 hours. Parabolic oxidation kinetics adequately described the corrosion process for about the first year, after which corrosion rates were constant, and lower than predicted from extrapolation of the initial part of the penetration versus time curves. With chromium concentrations between 2 and 9%, corrosion behavior was independent of chromium content, and corrosion was slightly less with Sandvik HT-9. Corrosion was nearly independent of surface preparation, but in two cases, the presence of mill scale on the surfacemore » prior to steam exposure seemed to retard oxidation in steam.« less