稀土变质消除铝合金压铸件中硬质点

Eliminating the Hard Spots in RE Modified Al Alloy Die Castings

初生硅和AlSiMnFe金属间化合物是造成铝合金压铸件中硬质点区域的主要因素 ,常规钠盐变质不能细化初生硅和Fe相 ,含有一定比例La ,Ce ,Pr ,Nd和Yb的特殊配制的稀土合金不仅能细化共晶硅 ,而且能细化初生硅并改善Fe相形貌。其中初生硅可细化到小于 10 μm ,因此能有效消除铝合金压铸件中的硬质点区域。

The hard spot area in aluminum alloy die casting mainly originates from the primary silicon and AlSiMnFe intermetallic compound. The primary silicon and Fe phase can not be refined with conventional sodium salt modification. Specially prepared RE almoy with a definite ratio of La, Ce, Pr, Nd and Yb not only can refine eutectic silicon but also refine primary silicon less than 10μm in size and improve morphology of Fe phase, so the hard spot area in aluminum alloy die casting could be eliminated effectively.