混合稀土对ZM5镁合金表_界_面张力及氧化膜性能的影响.pdf

Nov. 2010 铸 造 Vol .59 No.11 FOUNDRY 1205 · · !!!!! ! 应用技术 ! !!!!! （ ） 混合稀土对ZM5镁合金表 界 面张力 及氧化膜性能的影响 李华基，刘华堂，杨志远，洪观镇 （重庆大学材料科学与工程学院，重庆400030） 摘要：测量了不同RE添加量的ZM5镁合金不同温度下的表面张力，建立了界面反应润湿模型；根据氧化膜破裂能量 公式对熔体氧化膜性能进行了研究，并对氧化膜的高温失效进行了分析。结果表明：熔体中的RE可向熔体/氧化膜界面 集聚，参与氧化反应并提高氧化膜的致密度，有助于形成具有保护作用的氧化膜；同时RE 会增加界面反应层的厚度， 降低熔体/氧化膜的界面张力，使氧化膜不易破裂，并通过改变固-液界面张力方向来提高氧化膜与金属液间的粘附性。 关键词：混合稀土；表面集聚；界面张力；粘附性 中图分类号： + 文献标识码： 文章编号： TG146.2 2 A 1001-4977 （2010）11-1205-04 Effects of RE on the Interface Tension and Properties of Oxidation Film of ZM5 Magnesium LI Hua-ji, LIU Hua-tang, YANG Zhi-yuan, HONG Guan-zhen （College of Materials Science and Engineering, Chongqing University, Chongqing 400030, China） Abstract ：The surface tension of molten ZM5 alloy with different concentration of RE at different temperature has been measured and the wetting model of interface reaction has also been proposed. The oxidation film properties and failure at high temperature of molten ZM5 were investigated on the basis of the energy formula of oxidation film rupture. The results indicate that RE was adsorbed at interface between melt and oxidation film, which participated in the oxidation reaction and improved the density of oxidation film that was benefited to form protective oxidation film; Besides, RE could increase the thickness of interface reactive layer and reduce the interfacial tension to make the oxidation film hard to break. RE also increases the adhesion between oxidat