摘要
用电化学方法研究了Mg-14Li-1A1-0.1Ce合金在卤素溶液(NaX.X=F.CI.Br和I)中的腐蚀行为并用失重法测定其腐蚀速率,用扫描电镜(SEM)观察腐蚀后的表面形貌.利用XRD检定腐蚀产物的相组成.结果表明.合金在卤素溶液中的腐蚀速率由低到高的顺序是:NaF<NaI<NaBr<NaCI.经过48 h腐蚀后,合金在NaCl、NaBr和NaI溶液中的腐蚀产物层的组分为Mg(OH)_2,Lia_3Mg_7和Li_0.92Mg_4.08,而在NaF溶液中的腐蚀产物层的组分为Li_3Mg_7和Li_0.92Mg_4.08.此外,合金住NaF溶液中的电化学活性非常低,出现了钝化现象.电化学阻抗谱表明合金腐蚀产物层不能起到防止作用.
The corrosion behavior of Mg-14Li-lAl-0.1Ce in sodium halide NaX (X=F, Cl, Br and I) solutions was investigated by immersion test and electrochemical methods. Its corrosion rate in various solutions was accessed by mass loss method. The phase constituent, chemical composition and morphologies of corroded surface after 48 h immersed in different solutions were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results revealed that the corrosion resistance of Mg-14Li-lAl-0.1Ce in sodium halide solutions decreased in the order: NaF〉NaI〉NaBr〉NaC1. After immersed in NaI, NaBr, NaC1 solution respectively, the corrosion products consisted of Mg(OH)2, Li3Mg7 and Li0.92Mg4.0s, but for NaF solution, only Li3Mg7 and Li0.92Mg4.0s were found. Mg-Li-Al-Ce alloy showed passivation behavior in NaF solution. EIS results indicated that the corrosion product layer could not prevent the Mg-Li-AI-Ce alloy from further corrosion.
出处
《腐蚀科学与防护技术》
CAS
CSCD
北大核心
2011年第6期467-470,共4页
Corrosion Science and Protection Technology
基金
超轻材料与表面技术教育部重点实验室资助项目