%0 Journal Article
%T Experimental Investigation of the Phase Equilibria in the Al-Mn-Zn System at 400∼C
%A Tian Wang
%A Dmytro Kevorkov
%A Ahmad Mostafa
%A Mamoun Medraj
%J Journal of Materials
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/451587
%X Al-Mn-Zn ternary system is experimentally investigated at 400∼C using diffusion couples and key alloys. Phase relationships and homogeneity ranges are determined for binary and ternary compounds using EPMA, SEM/EDS, and XRD. Reported ternary compound T3 (Al11Mn3Zn2) is confirmed in this study and is denoted as 而2 in this paper. Two new ternary compounds (而1 and 而3) are observed in this system at 400∼C. 而1 is determined as a stoichiometric compound with the composition of Al31Mn8Zn11. 而3 has been found to have homogeneity range of AlxMnyZnz ( ˋat%; ˋat%; ˋat%). The binary compounds Al4Mn and Al11Mn4 exhibit limited solid solubility of around 6ˋat% and 4ˋat% Zn, respectively. Terminal solid solution Al8Mn5 is found to have maximum ternary solubility of about 10ˋat% Zn. In addition, ternary solubility of Al-rich 汕-Mn∩ at 400∼C is determined as 4ˋat% Zn. Zn-rich 汕-Mn∩∩ has a ternary solubility of 3ˋat% Al. The solubility of Al in Mn5Zn21 is measured as 5ˋat%. Based on the current experimental results, the isothermal section of Al-Mn-Zn ternary system at 400∼C has been constructed. 1. Introduction Automotive industry represents one of the most important markets for aluminum alloys. The use of aluminum and its alloys offers considerable potential to reduce the weight of an automobile body or engine without compromising performance and safety [1]. Many different elements including Mg, Cu, Zn, Mn, Si, and so forth are used to improve the properties of Al alloy for specific applications. Al-Zn based alloys have high strength and hardness, improved creep, wear resistance, and low density. It is well known that a small amount of Mn added to Al alloys plays a positive role in improving the fracture toughness, recrystallization, grain refinement, and resistance to stress corrosion fatigue of these alloys [1每3]. Because the Al-Mn-Zn system is an important ternary system for the development of Al alloys, it is essential to understand the phase relationships in the system. In addition, this system is an essential subsystem for AZ, AM-series magnesium alloys, high strength steels, and for galvanizing-related alloy systems [4, 5]. The three constituent binary systems were reasonably studied. Khan and Medraj [6] reevaluated the Al-Mn system which was in good agreement with most of the experimental results [7每10]. From their work [6], thermodynamic calculation almost reproduced the EPMA results of Minamino et al. [11]. Their calculation was consistent with the observation of Okamoto [12] who suggested a smooth continuous liquidus curve between the terminal 汛-phase (BCC)
%U http://www.hindawi.com/journals/jma/2014/451587/