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E. Silva, L. Batista, B. Callegari, I. Feierabend, R. Buzolin, R. Coelho, F. Warchomicka, G. Requena, H. Pinto:
"Casting in the Semi-Solid State of ZK60 Magnesium Alloy Modified with Rare Earth Addition";
Talk: THERMEC 2013, Las Vegas; 2013-12-02 - 2013-12-06; in: "THERMEC 2013", (2013).

In this work, the casting process under mechanical agitation in the semi-solid state was investigated for the production of ZK60 magnesium alloy modified with the addition of 2.5% wt of mischmetal. The results show that this process enables the production of ingots with homogeneous chemical composition and free of shrinkage, inner defects and internal oxidation. The as-cast microstructure consists of an -Mg matrix with globular grains reinforced by a grid of distinct intermetallics of Mg-Zn, Mg-Zn-RE and Mg-RE type along the grain boundaries. The yield strength at room temperature undergoes more than 50% increase during direct T5 aging, thus reaching 170 MPa. At 300°C, however, the dispersion of nanometric precipitates does not modify the hot deformation behavior of the aged alloy, which undergoes dynamic recrystallization in a similar manner to the as-cast alloy. DRX at 300°C is fastest for the alloy solution-treated at 500°C.