ABSTRACT

The Al-Si-Cu-Mg-Ni alloy is a commonly used piston alloy. In this work, different amounts of phosphorus modifier and Al-2P (Al-2%P) master alloy modifier were added to the original alloy. The ultrasonic melt treatment method was also applied to improved the microstructure of near-eutectic multi-cast Al–Si alloys. Investigation was performed by means of optical microscopy and scanning electron microscopy. The results show that the effect of Al-2P master alloy modifier is more stable. However, the phosphorus modifier requires a higher amount of addition to achieve a refinement effect similar to that of the Al-2P modifier. The external ultrasonic field mainly acts on the AlP particle. The heterogeneous nucleation of the primary Si phase and the AlP clusters formed by the phosphorus modifier are more aggregated than the fine-dispersed AlP particles formed by the Al-2P master alloy modifier in the melt. Hence the ultrasonic melt treatment is more effective for the phosphorus modification.

摘要

Al-Si-Cu-Mg-Ni合金是一种常用的活塞合金。在这项工作中，在原始合金中加入了不同量的磷改性剂和 Al-2P (Al-2%P) 中间合金改性剂。超声熔体处理方法也被应用于改善近共晶多铸铝硅合金的显微组织。研究是通过光学显微镜和扫描电子显微镜进行的。结果表明，Al-2P中间合金改性剂的效果更稳定。但是，磷改性剂需要更高的添加量才能达到类似于Al-2P改性剂的细化效果。外部超声场主要作用在AlP颗粒上。由磷改性剂形成的初生 Si 相的异质成核和 AlP 团簇比由 Al-2P 母合金改性剂在熔体中形成的细分散的 AlP 颗粒聚集得更多。因此，超声波熔体处理对磷改性更有效。