NUST MISIS, Chair for Metal Forming, Moscow, Russia:

V. V. Doroshenko, Engineer, Junior Researcher, Laboratory of Hydrocarbon Catalysis and Processing, Candidate of Technical Sciences, e-mail: v.doroshenko@mail.ru
E. A. Naumova, Associate Professor, Candidate of Technical Sciences, e-email: jan73@mail.ru
M. A. Barykin, Engineer, e-mail: mr.barykin97.97@mail.ru
A. N. Koshmin, Engineer of the 1^st Category, e-mail: koshmin.an@misis.ru

The results of studies of the casting properties of aluminum-calcium alloys in comparison with known silumins are presented. The alloys were prepared in a resistance electric furnace based on pure components and ligatures. The pouring was carried out at temperatures of 700 and 780 ^oC for silumins and aluminum-calcium alloys, respectively, obtaining flat ingots for subsequent remelting and casting of samples. All samples were poured with the same superheat above the liquidus temperature of 100 ^oC. It is shown that alloys with calcium (both eutectic and hypereutectic) are not inferior to widely used silumins in terms of fluidity, hot brittleness, and form fillability. For the first time, the parameters of difficult shrinkage were determined in a T-shaped sample of aluminum-calcium alloys in comparison with silumins. It is shown that eutectic alloys have comparable values of linear shrinkage with eutectic silumins, and the shrinkage of the hypereutectic alloy Al – 6% Ca – 3% Mn exceeds the shrinkage of the hypereutectic silumin AK18 by 1.5 times (1.5 and 1%, respectively). A high deformation plasticity during hot and cold rolling of the Al₆Ca3Mn hypereutectic alloy has been established. The overall reduction ratio after applying both rolling methods exceeded 95%. The primary crystals retained their compact size and shape. It has been established that the strength properties of cold-rolled sheets from the Al₆Ca₃Mn hypereutectic alloy correspond to the strength values of the AD31 industrial aluminum alloy, which allows to consider it promising in those industries where a combination of high manufacturability with reduced thermal and electrical conductivity is required.

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