(1. 蘇州熱工研究院 壽命評估中心，蘇州 215004；
2. 北京科技大學(xué) 新材料技術(shù)研究院，北京100083)
摘 要: 采用掃描電子顯微鏡和X射線衍射儀研究了Cl−對690合金在高溫高壓水中腐蝕行為的影響。研究表明：690合金內(nèi)外表面狀態(tài)對其腐蝕形貌有顯著影響，Cl−使得表面形成的鈍化膜不均勻，出現(xiàn)較多的點(diǎn)蝕坑。溶液中的Cl−能夠影響腐蝕產(chǎn)物膜的結(jié)構(gòu)。當(dāng)溶液中不含有Cl−時，腐蝕產(chǎn)物膜為雙層結(jié)構(gòu)，外層腐蝕產(chǎn)物為顆粒狀；當(dāng)溶液中含有Cl−時，腐蝕產(chǎn)物膜具有單層結(jié)構(gòu)。XRD結(jié)果表明：兩種環(huán)境中的鈍化膜產(chǎn)物主要由Cr2O3、NiFe2O4、NiO等氧化物組成，但含Cl−條件下的氧化物較少。
關(guān)鍵字: 690合金；腐蝕；Cl−；鈍化膜
中圖分類號：TG172 文獻(xiàn)標(biāo)志碼：A
high temperature and high pressure water solution
（1. Life Assessment Center, Suzhou Nuclear Power Research Institute, Suzhou 215004, China;
2. Institute for Advanced Material and Technology, University of Science and Technology Beijing, Beijing 100083, China）
Abstract:The effect of Cl− on the corrosion behaviors of alloy 690 in high temperature and high pressure solution was investigated by SEM and XRD. The results show that the conditions of inside and outside surface have apparent effect on the corrosion morphology of alloy 690. The surface of passive film formed in solution with Cl− is uneven, and a lot of pits can be found. The Cl− of electrolyte has great effect on the structure of corrosion product. The corrosion product film formed in solution without Cl− has the double layer structure. The corrosion scale formed in the Cl−-containing solution has a monolayer. The outer sub-film is composed of grainy crystal. The XRD results show that the passive film in the two environments mainly consists of Cr2O3, NiFe2O4, NiO and other oxides, but there is fewer oxides in the film formed in solution with Cl−.
Key words: alloy 690; corrosion; Cl−; passive film
