A novel method to induce the precipitation of primary silicon in commercial near eutectic Al-Si alloys

A novel method to induce the precipitation of primary silicon in near eutectic Al-Si alloy (ZL109) was investigated in this work. Ni-38 wt.%Si master alloy was added into the ZL109 alloy melt to induce the precipitation of primary silicon, and this technology was optimized by considering several parameters, such as the inducement temperature, the addition level, and the holding time. It was found that there was good inducement efficiency of Ni-38 wt.%Si master alloy for ZL109 alloy when the addition level was above 1% and held at 740 °C for above 30 min. Meanwhile, the efficiency can last for above 600 min. Finally, the precipitation of primary silicon in ZL109 alloy with Ni-38 wt.%Si master alloy was not induced by the increasing silicon containing, but induced by the addition of Ni-38 wt.%Si master alloy.