混合稀土对ZM5镁合金熔炼起燃温度的影响

镁合金在大气条件下熔炼和浇注极易氧化燃烧，是阻碍镁合金推广应用的重要因素。目前一般采用熔剂覆盖和气体保护法熔炼生产镁合金，或采用半固态射铸成形工艺以降低作业温度，但都存在看不少缺点。通过合金化的方法来达到镁合金阻燃的目的将是发展方向。针对ZM5镁合金，研究了混合稀土及其加入量对起燃温度的影响，并与纯稀土的阻燃效果进行了比较。结果表明，添加0.12％混合稀土能大大提高镁合金的起燃温度，有望成为一种能推广应用的阻燃镁合金。

Effect of Mischmetal Additions on the Ignition Temperature ofMolten ZM5 Magnesium Alloy

Magnesium alloy is prone to burning during its melting and casting in air, which is a major factor in obstructing its application. Fluxes and cover gases are currently used for the melting and production processes, and semi solid thixocasting is also used to lower the operation temperature, but there still remain many problems. Alloying is a promising method of preventing Mg from burning. The effect of mischmetal additions on the ignition temperature of ZM5 Mg alloy was investigated and compared with that of pure rare earths. It is shown that an addition of 0.12 % mischmetal can greatly heighten the ignition point and such an alloy can be widely applied.