Horizontal single belt casting for the competitive manufacturing of ferrous and light metal alloy sheet material

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Sheet aluminum and steel products are currently being produced globally, by continuously casting large slabs and then sequentially rolling them down in hot and cold rolling mills, so as to form thin sheet material. These processes are energy and manpower intensive, and will have to be replaced with greener, Near Net Shape Casting (NNSC) Processes. The most viable of these is the Horizontal Single Belt Caster, (HSBC), which provides for the friction-free, unconstrained solidification of steel, aluminum and magnesium strips, followed by in-line rolling down to final gauge sheet. With this research we will target AA6xxx and AA5xxx aluminum alloy systems, magnesium AZ31 alloy, and new grades of High Strength Steels, HSS, (TWIP and TRIP) on our HSBC pilot caster. Only an HSBC can handle the production of HSS grades, since they work harden too rapidly for conventional hot rolling mills handling thick sections. As these new grades of HSS steels represent a new era for steelmakers, being twice the strength of regular steels, with much greater ductility prior to failure (~+65% elongation), they can be used as thinner sections to lightweight cars, and/or to significantly strengthen critical components. With this research, we shall continue our modeling the first few mille-seconds of melt/substrate (water cooled belt) when the surface quality of the sheet is determined. The commercial implications of the near net shape casting programs are also very significant, with at the very least, 30% decreases in capital and operating costs projected vs. conventional slab caster-hot rolling mill operations. Last year, Salzgitter GmbH, Germany, announced their intentions to construct the world's first commercial size HSBC caster (or DSC in their parlance, for "Direct Steel Casting"). They are doing this for the production of "difficult to make" ultra-high strength ultra high ductility, steel alloys, which become too strong for thinning down in hot rolling mills. Further, the horizontal single belt caster (HSBC), would certainly be a much better match for the output of current integrated steel mills than a Twin Roll Caster (TRC), and would allow for the thermo-mechanical processing needed for advanced steel properties.