阻燃镁合金ZM5-0.1RE氧化动力学研究

Oxidation Kinetics of the ZM5-0.1RE Magnesium Alloy

在ZM5镁合金中添加0.1%混合稀土时,阻燃效果最佳,镁合金起燃温度提高到800℃以上。利用光学显微镜分析了ZM5-0.1RE氧化膜的表面形貌。X射线衍射分析(XRD)和扫描电镜分析(SEM&EDS)表明,这层致密氧化膜由RE2O3、MgO、Al2O3、Mg17Al12组成,氧化膜致密度大于1,具有保护作用。高温氧化动力学研究显示,温度为700℃时,合金的高温氧化动力学曲线符合抛物线规律,在这个温度下,氧化膜增重很少,保护性好。

The ignition temperature of ZM5 magnesium alloy can be increased greatly by adding mischmetal(MM)composed of La and Ce element,increased to more than 800 ℃ with 0.1% MM addition,obtaining desirable ignition-proof effects.The surface morphology of oxidized film of ZM5-0.1RE alloy was observed by optical microscope(OM).The results reveal that the compact film is composed of RE2O3,MgO,Al2O3 and Mg17Al12 with densification degree more than 1,exhibiting excellent protection performance.The oxidation kinetic curves of the alloy is accordant with the parabola principle at 700 ℃,which is controlled by diffusion,showing good oxidation resistance.