Abstract
The potential for lightweight design solutions in the automotive industry has not yet been fully exploited. Magnesium as the lightest structural metal bears a significant weight saving potential compared to steels and aluminum. Cast magnesium components are widely used e.g. as gear box houses. The production and processing of magnesium sheets material is currently hampered by the low formability of magnesium and high costs. The low formability of magnesium sheets requires a high number of rolling passes to roll cast slabs to final gauge, which leads into a cost issue for the production of magnesium sheets. In order to improve the formability new magnesium alloys are developed. An alternative cost efficient production route for magnesium sheets with improved properties is the feedstock production by twin roll casting (TRC). In the twin roll casting process liquid metal is pumped from furnace or cast over a pipe into a tundish. Then the melt is dragged into the roll gap of a pair of counter rotating, internally cooled rolls. The metal solidifies upon contact with the cooled rolls and gets rolled to a strip.
This paper reports on results of rolling experiments on twin roll cast strips of established and new developed magnesium alloys, like ZAX210 (Mg-2Zn-1Al-0.5Ca), which has been produced with different process routes. The influence of the strip properties and the rolling process parameters like temperature and degree of deformation on the microstructure, the texture and the mechanical properties of the strip is presented and discussed. In the future, the design of new magnesium alloys for sheets needs to be combined with the development of the production process in order to optimize sheet properties.
