Direct chill casting is a necessary prerequisite for cost competitive processing of aluminum and steel sheet and extrusion products, but is still not widely available for magnesium alloys. This was the major task for the development of a vertical direct chill casting process for magnesium alloys and the resulting pilot casting plant at the LKR premises in Austria, where testing began in early 2001. The R&D work concentrated on safety issues, easy casting operation by remote control, high productivity, and high-quality product. The development program encompassed the complete processing route from melting, alloying, casting, heat treatment, and finally to the extrusion of magnesium profiles. Extrusion billets made from the alloy AZ31 were investigated for grain size distribution over the cross section as well as macro segregation. A multi-chamber profile was extruded and investigated for mechanical and microstructural properties. Studies were completed by the end of 2002, when MAGNUMCAST~R, the new vertical direct chill caster, was ready for industrial application (Table I).
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