Variations of Solute Concentration in the Crucible during Hot Chamber Die-Casting Process
Compositional variations of magnesium alloys AZ91D and AM60B in a crucible during hot-chamber die casting process have been investigated. The sampling of molten metal for chemical composition analysis was carried out at three positions (A: bottom, B and C: 100 and 300 mm upside from the bottom, respectively) within a crucible of 600 mm in depth. The picked molten metal was poured into a steel mold to cast into a rod 40mm diameter and 120mm length. Results show that heavier elements such as Al, Zn, Mn, Fe, etc. were concentrated at the bottom of crucible, which is resulted from long-time, repeated casting operations without bailing out. The macro segregation of alloying elements and impurities are partly caused by the reaction between the alloying elements. Short-periods of holding time up to 250 minutes, however, did not significantly change the concentration of Al and Zn at the entrance of gooseneck.
W.Ke, E.H.Han, Y.F.Han, K.Kainer and A.A.Luo
M. C. Kang et al., "Variations of Solute Concentration in the Crucible during Hot Chamber Die-Casting Process", Materials Science Forum, Vols. 488-489, pp. 321-324, 2005