DESIGN OF NEW CASTING ALLOYS OF Al-Mg-Si-Mn SYSTEM WITH ALLOYING ADDITIONS, ITS STRUCTURE AND MECHANICAL PROPERTIES
DOI:
https://doi.org/10.7494/mafe.2017.43.3.141Keywords:
casting alloy, Al-Mg-Si system, Li addition, precipitation, heat tteatmentAbstract
The strength of Al-Mg-Si-Mn casting alloy strongly depends on Mg content in solid solution and precipitation of strengthening phases. Alloys with the nominal composition AlMg5Si2Mn with addition of Li and Ti+Zr were studied by means of differential scanning calorimetry (DSC), transmission electron microscopy (TEM) and energy dispersive X-Ray analysis (EDX). DSC measurements show that the eutectic melting temperature was about 595°C and it is higher than that of commercial A356 casting alloy. The macro- and microhardness tests show that in as-cast state hardness were higher than for A356 and continuously growth during artificial aging. TEM investigations reveal that during artificial aging three different precipitation types are forms in the alloy matrix. Two of them belong to the different structures of Mg2Si precipitates. Appearance of the third one identified as d’-Al3Li phase represent that Al-Mg-Si system can be successfully used for designing of Li-containing casting alloy which is not developed yet.
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Eigenfeld K., Franke A., Klan S., Koch H., Lenzcowski B., Pflege B.: New developments in heat resistant aluminum casting materials. Casting Plant and Technology International, 4 (2004), 4–9
Petkov T., Kunstner D., Pabel T., Kneibl C., Schumacher P.: Optimizing the Heat Treatment of a Ductile AlMgSi-alloy. Giesserei-Rundschau, 59 (2012), 194–200
Ji S., Watson D., Fan Z., White M.: Development of a super ductile die cast Al-Mg-Si alloy. Materials Science and Engineering, 556 (2012), 824–833. http://dx.doi.org/10.1016/j.msea.2012.07.074
Wuth M.C., Koch H., Franke A.J.: Production of steering wheel frames with an AlMg5Si2Mn alloy. Casting Plant and Technology International, 16, 1 (2000), 12–24
Shabestari S.G., Shahri F.: Influence of modification, solidification conditions and heat treatment on the microstructure and mechanical properties of A356 aluminum alloy. Journal of Material Science, 39 (2004), 2023–2032
Pirš J., Zalar A.: Investigations of the distribution of elements in phases present in G-AlMg5Si cast alloy with EDX/WDX spectrometers and AES. Microchimica Acta, 101, 1–6 (1990), 295–304
Fridlyander J.N., Bratukhin A.G., Davydov V.G.: Soviet Al-Li Alloys of Aerospace Application, Aluminum-Lithium. Proceedings of the Sixth International Aluminum-Lithium Conference in Garmisch-Partenkirchen, Germany, Peters M. and Winkler P.-J. eds., Vol. 1, 1991, 35–42
Boyko V., Link T., Korzhova N., Mykhalenkov K.: Microstructure characterization of AlMg5Si2Mn casting alloy. In: Materials Science and Technology (MS&T) 2013, October 27–31, Montreal, Quebec, Canada, 2013, 1331–1338