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Since magnesium has very low density, it is always attractive in aerospace and transportation industries. However, due to high reactivity with environment, melting, alloying and casting of magnesium is always faced with problems about melt quality. So these alloys have low resistance to oxidation and combustion. Recent studies show that addition of alkali earth metals reduces the oxidation tendency of molten magnesium alloys. This study aimed to investigate the effect of calcium on oxidation resistance of magnesium alloys melt through microstructural studies, XRD and melt oxidation test. Results show that addition of calcium forms intermetallic compounds such as AL2Ca. Formation of these type of compounds in grain boundaries with surface oxide film of CaO, prevents the melt oxidation and minimizes the oxidation during atmosphere exposure. The most important advantage of these alloys is minimizing the use of shielding gases like SF6 which is considered a greenhouse gas that causes many environmental problems.
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Materials and Manufacturing Engineering, vol. 24, pp. 99–102.
B.C., H.N., 2004, “Automotive Applications of Magnesium and Its Alloys”. Trans. Indian Inst. Met., vol. 57, pp. 397–408.
Shuang-Shou Li, Bin Tang and Da-Ben Zeng, 2006, “Effects and mechanism of Ca on refinement of AZ91D alloy”. Journal of Alloys and Compounds, pp. 317–321.
Dong-Bok Lee, Lee-Seok Hong and Young-Jig Kim, 2008, “Effect of Ca and CaO on the High Temperature Oxidation of AZ91D Mg Alloys”. Materials Transactions, Vol. 49, No. 5, pp. 1084–1088.
S. kim, 2014, “Magnesium based alloy for high temperature and manufacturing of them”. U.S patent.
Ha Seong-Ho, LEE Jin-Kyu and JUNG Seong-Boo, 2006, “Behavior of CaO and Calcium in pure Magnesium”. Rare Metals, vol 25, pp. 150.
M. Holtzer and. A. Bobrowski, 2008, “Magnesium melt protection by covering gas”. Archives of Foundry Engineering, Vol 8, pp. 131–136.
T. W. Lee, 2015, “Microstructural evaluation of oxide layers in CaO-added Mg alloys”. Journal of Alloys and Compounds, pp. 5–10.
B. H. Choi, B. S. You and I. M. Park, 2006, “Characterization of Protective Oxide Layers Formed on Molten AZ91 Alloy Containing Ca and Be”. Metals and Materials International, vol. 12. pp. 63–67.
J. Hwan, 2013, “Effect of CaO Addition on Microstructure and Damping Capacity of AM50 Magnesium Alloy”. Materials Transactions.
S. K. Kim, 2011, “Design and development of high performance Mg alloys”. Design, Processing and Properties, no. 978-953-307-520-4.
Y. Chen, 2013, “Effects of the addition of Ca and Sb on the microstructure and mechanical properties of AZ91 magnesium”. Materials Science & Engineering, pp. 262–267.
- Effect of Ca on Oxidation Resistance of Magnesium Alloys (AZ91)
Hassan Saghafian Larijani
Ghasem Eisaabadi. B
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