Complex modification effect by ZrAlSi intermetallic and element Sr on the microstructure and mechanical properties of hypereutectic Al-Si alloys

In this study, the morphological evolution of ZrAlSi intermetallic in ternary Al-Si-Zr alloys was investigated. In hypereutectic Al-18Si alloy, the introduction of Zr results in the formation of blocky ZrAlSi particles. Besides, there form almost no primary Si, while replaced by ZrAlSi. Using ZrAlSi to modify primary Si and Sr to modify eutectic Si, complex modification effect can be realized in an Al-Si multicomponent piston alloy. Correspondingly, the mechanical properties were significantly improved. (C) 2013 Elsevier B. V. All rights reserved.