论文部分内容阅读
利用OM,SEM/EDS和XRD等测试手段,研究了模拟还原性全挥发处理(AVT(R))和给水加氧处理(OT)工况下Cl-及Cl-/SO42-对超临界机组水冷壁管材料15CrMoG的腐蚀特性的影响。结果表明:在AVT(R)工况下试片表面氧化物颗粒比OT工况更为均一且分布均匀;在含Cl-或Cl-/SO42-模拟OT溶液工况中,试片腐蚀程度随离子浓度增大而增大。在相同离子浓度的OT工况溶液中试片的腐蚀程度比AVT(R)更严重,且在同一工况下相同离子浓度的Cl-/SO42-比Cl-侵蚀性强。由于点蚀的自催化作用,在模拟AVT(R)和OT工况溶液中试片均会发生严重局部腐蚀。EDS结果表明,两种工况不同离子溶液中试片的点蚀坑内均未发现Cl-,但测得S的含量与水冷壁管成分相比显著增高。
The effects of Cl- and Cl- / SO42- on the supercritical water cooling of the supercritical units under simulated reductive total volatility (AVT (R)) and feedwater oxygenation (OT) conditions were studied by means of OM, SEM / EDS and XRD. Effect of Corrosion Characteristics of Wall Material 15CrMoG. The results show that the oxide particles on the surface of the test piece are more uniform and distributed under the condition of AVT (R) than that of the OT condition. The corrosion degree of the test piece in the condition of Cl- or Cl- / SO42- Ion concentration increases and increases. The corrosion degree of the test piece in OT working solution with the same ion concentration is more serious than that of AVT (R), and Cl- / SO42- of the same ion concentration is more aggressive than Cl- in the same working condition. Due to the autocatalytic action of pitting corrosion, severe localized corrosion of test coupons occurs in simulated AVT (R) and OT working solution. The results of EDS showed that no Cl- was found in the pits of the test pieces in different ionic liquids. However, the content of S was significantly higher than that of the water-cooled wall tubes.