Elaheh Maleki - Engineering Group, Iran University of Industries and Mines
Saman Mostafapoor - School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran
Mehdi Malekan - School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran
Masoud Emamy - School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran

In this work, the effect of variation of Mg to Cu ratio for Al-۱۵Zn-xMg-yCu (x+y=۵) was studied using computer aided cooling curve analysis method. In this respect, different amounts of ۰.۲۵, ۰.۶۶, ۱.۰۰, ۱.۵, and ۴ were selected for Mg/Cu ratio. Then, cooling curve analysis was performed for studied alloys. The provided data used to extract solidification parameters of the specimens. It was seen that, Mg/Cu ratio affects solidification behaviour of the alloy. The results showed that the influence of Mg/Cu ratio on solidification could be divided into two parts of ratios smaller than ۱ and those larger than that. For Mg/Cu<۱, solidification range, especially affected by solidus temperature, increases when the ratio climbs. In this ratio region, nucleation undercooling reduced with increment of Mg/Cu ratio although recalescence undercooling shows an increment in this region. For Mg/Cu>۱ both undercoolings vary conversely compared to Mg/Cu<۱ region.

Al-Zn-Mg-Cu, Aluminum Alloy; Solidification; Thermal Analysis, Computer Aided Coolong Curve