细化及变质方法对A356铝合金微观组织的影响

Influence of Refining and Modification Manners on Microstructure of A356 Aluminium Alloys

在对比研究细晶铝锭和铝钛中间合金2种不同加钛细化方法的基础上,研究锶、稀土、锶+稀土不同变质方法处理后A356铝合金的铸态微观组织变化。结果表明:细晶铝锭细化效果较铝钛中间合金好,经细晶铝锭+锶+稀土联合处理的A356铝合金,晶粒细小,变质充分,针孔较少,组织均匀,是一种优良的细化变质方法。

On the basis of studying two different Ti addition refining manners of grain-refining aluminium ingots and aluminium-titianium master alloys, the effect of different modification manners, such as strontium, rare-earth, strontium combined with rare-earth, on the as-cast microstructure of A356 aluminium alloys was studied. The results show that the refining effect of grain-refining aluminium ingots is more efficient than aluminium-titianium master alloys. A356 aluminium alloys modified with grain-refining aluminium ingots combined with strontium and rare-earth has refined grains, decreasing pinholes and homogeneous microstructure, thus refining aluminium ingots ＋ strontium ＋ rare-earth is an excellent modification manner.