ZM5-0.1%RE阻燃镁合金表面氧化膜的结构及阻燃机理

Structure and Flame-retardant Mechanism of the Surface Oxide Film on ZM5-0.1%RE Magnesium Alloy

摘要: 为提高镁合金的起燃温度,在ZM5镁合金中添加了质量分数为0.1%的混合稀土(RE),对该合金表面进行了EDS、SEM和XRD分析.结果表明:在高温熔炼时合金表面生成了一层由RE2O3、MgO、Al2O3、Mg17Al12组成的厚度为2.5~3.5 μm的致密氧化膜;氧化膜最外表面没有稀土,而在基体和最外表面层之间混合稀土含量很高,质量分数为26.39%;稀土比镁更易氧化,致密的氧化膜抑制了基体镁合金的进一步氧化.

Abstract: 0.1% mixed rare earth(RE) was added into the ZM5 magnesium alloy to improve its ignition temperatare,and EDS,SEM and XRD were used to characterized the surface oxide film.The results show that a layer of tight oxide film with 2.5-3.5 μm thickness and composed of RE2O3,MgO,Al2O3 and Mg17Al12 was formed on the surface of ZM5 magnesium alloy.No RE elements were detected at the outmost surface of the oxide film.However,RE had the highest content of 26.39% between the base metal and the outmost surface.The tight surface oxide film prevented the further oxidation of the base magnesium alloy.