Effect of Ni on eutectic structural evolution in hypereutectic Al-Mg2Si cast alloys

▶ By the injection of rod-like NiAl3 phase in Al-Mg2Si alloys, Al-Mg2Si binary eutectic structure gradually evolves into Al-Mg2Si-NiAl3 ternary eutectic. ▶ The ternary eutectic presents a unique double rod structure that rod-like NiAl3 and Mg2Si uniformly distribute in Al matrix. ▶ The mechanism of structural evolution was analyzed in terms of the detailed microstructural observations. ▶ The high temperature (350 °C) tensile strength of the alloy increases by 23% due to the eutectic structural evolution.