Abstract: Effect of solidification range on hot tearing susceptibility of Al-Mg alloy castings with the Mg content in a range of 5 to 7 mass% was investigated in this study. As-cast microstructures of Al-5mass%Mg and Al-7mass%Mg alloys showed the distribution of β-Al3Mg2 phase in Al matrix. In Al-7mass%Mg alloy, more β-Al3Mg2 eutectic particles were distributed, while no significant difference in grain size was shown. The hot cracking tendency of Al-Mg alloys reduced with increasing the Mg content. As a result of thermodynamic calculation by FactSage 7.1, enrichment of Mg reduced the freezing range in both Scheil and equilibrium cooling.
Authors: Young-Ok Yoon, Seong-Ho Ha, Bong-Hwan Kim, Hyun-Kyu Lim, and Shae K. Kim
Keywords: Al Mg alloy, Hot tearing susceptibility , Freezing range