(上海交通大学 金属基复合材料国家重点实验室， 上海 200030)
摘 要: 镁合金熔炼时会发生剧烈的燃烧，因此必须采取有效的措施对其加以保护。合金化阻燃是一种理想的阻燃方法。从热力学角度对镁合金元素氧化方式的差异作出了解释，并采用统一的氧化模型分析了两种氧化膜的形成过程。研究结果表明，添加少量的Be或Ca可以提高Mg9Al0.5Zn合金的燃点。但是，两种合金中基体元素Mg与合金元素Be和Ca的氧化方式并不相同。加入Be后，Mg发生外氧化，Be发生内氧化。加入Ca后，Ca发生外氧化，Mg发生内氧化，因此合金表面氧化膜的物相组成和元素分布也不相同。
关键字: 铍； 钙； 镁合金； 热力学
（College of Materials Science and Engineering, Shanghai Jiaotong University，Shanghai 200030, P.R.China）
Abstract:When being melted， magnesium alloys were prone to burn heavily, so special measures must be taken to protect it from ignition. Alloying is a effective method to keep magnesium alloy from burning intensively. In terms of thermodynamic principle， the different oxidation behaviors of these two kinds of alloys were analyzed. The thermodynamic forming processes of the oxide films were also explained by constructing a simplified model. When alloy elements of Be and Ca were added， the ignitionproof property was improved significantly. The structure and chemical compositions of the oxide film were investigated by XRD and AES. The results revealed that Be is oxidized under the MgO layer and Ca is oxidized in the outmost layer.
Key words: beryllium; calcium; magnesium alloy; thermodynamics
