R Khorshidi - PhD student, Faculty of Materials Science and Engineering, Semnan University, Semnan, Iran,
A Hasani - Assistant professor, Faculty of Materials Science and Engineering, Semnan University, Semnan
A. Honarbakhsh Rauof - Associated professor, Faculty of Materials Science and Engineering, Semnan University
M. Emamy - Full professor, School of Metallurgy and Materials, College of Engineering, University of Tehran

In recent years, in situ Al-Mg2Si composites have been introduced as a new group of particulate metal matrix composites which contain hard particles of Mg2Si in Al-matrix. Unfortunately, coarsening ofMg2Si particles deteriorates the mechanical properties so that it is an important obstacle for the wideapplication of this type of composites. Our previous investigations depicted that the addition of Na and Mn as alloying elements and solution treatment in the different range of temperature can refineAl-Mg2Si composite structure and improve tensile properties. Selection of the optimal refinement condition to achieve maximum tensile properties of Al-15%Mg2Si composite is a multiple attribute decision making (MADM) problem where some criteria must be considered in decision making. In present research, technique for order preference by similarity to ideal solution (TOPSIS) method isemployed in solving the case study problem. Weights of each criterion are determined by using an analytic hierarchy process (AHP) method. Empirical findings in this study represented that TOPSIS method might lead to the choice of refined Al-15%Mg2Si via solution treatment at 450 ˚C as the preferred alternative

Al-Mg2Si composites; multiple attribute decision making; AHP; TOPSIS