Ce^（3＋）对LC_9合金在含Cl~－水溶液中缓蚀作用的研究

A Study of Inhibition Action of Ce￣(3+) Cation on Corrosion of LC_9 Alloy in Aqueous Chloride Solutions

用失重法、电化学测量法研究了一些稀土元素离子对ＬＣ９合金在３．５％ＮａＣｌ溶液中腐蚀行为的影响，并将ＣｅＣｌ３的缓蚀性与同等浓度的８１０８复合缓蚀剂、０．３％Ｋ２Ｃｒ２Ｏ７水溶液进行了比较，根据失重实验的失重量计算腐蚀率和缓蚀率，同时也根据试片表面状态、色泽、破损面大小评估试片的耐蚀性、通过动电位扫描法测极化曲线，恒电位法测诱导期的方法来确定孔蚀电位Ｅｂ、保护电位Ｅｐ及其它参数。结果表明，ＣｅＣｌ３是ＬＣ９合金在含Ｃｌ－水溶液中的良好缓蚀剂，其缓蚀作用优于其它两种缓蚀剂。Ｃｅ３＋离子改善了ＬＣ９合金的表面膜，抑制了氧还原反应，减弱了对腐蚀的敏感性。ＣｅＣｌ３是阴极型和沉淀模型缓蚀剂。

The effect of some rare earth element canon on corrosion behavior of LC9 alloy in 3. 5%NaCl solution was studied by weight loss test and electrochemical measurment.The inhibition effect of CeCl3 was compared with 8108 compound inhibitor of the same concentration added to 0. 3%K2Cr2O7 aqueous solution. The corrosion rate and inhibition rate were determined from weight losses in the weight loss test and anticorrosion property of the test specimen LC9 was evaluated from the state, the luster and the damage magnitude of its surface. The polarization curve, the pitting patential, Eb, the protection patential, Ep,and other parameters were measured separatively by the potentiodynamic scanning method and the potentiostatic method. The results show that CeCl3 is a good inhibitor of LC9 alloy in aqueous chloride solutions and its inhibition action is better than the action of other inhibitors. The Ce3+ canons improve the surface film of LC9 alloy, suppress the oxygen reduction reaction and diminish the sensitivity of corrosion. CeCl3 is a type of cathodic precipitate film-forming inhibitor.