作　　者： ; ; ; ; ;

机构地区： 中南大学材料科学与工程学院

出　　处： 《中国腐蚀与防护学报》 2008年第4期205-209,共5页

摘　　要： 用X射线衍射(XRD)、扫描电镜(SEM)、能谱分析(EDS)、析氢法、动电位极化及浸泡实验等手段研究了添加微量稀土元素Ce对AZ91镁合金微观组织及耐蚀性的影响,并从热力学角度分析了Ce对提高合金耐蚀性的影响机制。结果表明,稀土Ce细化了合金的微观组织,使β-Mg17Al12相变得断续、弥散,成分分布更为均匀,生成了Al4Ce相及Mg-Al-Mn-Ce-Fe的金属间化合物;稀土Ce使合金在3.5%NaCl溶液中的自腐蚀电位升高,与Al、O生成了不连续的保护性氧化膜,提高了合金的耐腐蚀性能;添加0.5mass%Ce时合金的耐蚀性最佳。 The effects of rare earth Ce addition on the microstructures and corrosion resistance of AZ91 magneisum allovs were studied by XRD, SEM, EDS, collecting gas, potentiodynamic polarization and immersion test. The mechanics of the corrosion resistance increasing with Ce addition was analyzed in thermodynamic. The results showed that, the addition of Ce refined the mierostructure of AZ91, β-Mg17Al12 phase was broken and dispersed in the matrix with more homogeneous composition. The Al4Ce phase and Mg-Al-Mn-C-Fe intermetallics were observed in alloy. The addition of Ce increased the corrosion potential of alloy and resulted in the formation of Al-Ce-O protective oxidation film reacted bv Ce,Al and O elements. The alloy has the best corrosion resistant property with 0.5 mass% Ce content.

关 键 词： 镁合金 微观组织 耐蚀性

领　　域： [金属学及工艺] [一般工业技术] [金属学及工艺] [金属学及工艺] [金属学及工艺]