The growing demand of steel products in a rapidly developingeconomy and increasing levels of imports in the Arab Worldprogress the development of local steel production. The steelindustry develops along the processes most appropriate to localresources: DR processes and EAF operation.

Today, the numerical simulation of fluid dynamic phenomena(CFD) in steelmaking applications is state of the art. Thelatest simulation results for the BOF and AOD as well asthe thin strip casting process are described. The basicinfluence of the process parameters, e.g. blowing andstirring rate, vessel dimension, location of top lance, numberand arrangement of porous plugs, on the converter meltflow and mixing time is simulated. In the case of thin stripcasting, the free melt flow on the moving belt is influencedby an induced electromagnetic field. The respective MHD(magneto-hydrodynamic) is presented.

Industrial trials were carried out at the ArcelorMittal Isbergues slab continuous caster with the HJN (Hollow Jet Nozzle) previously developed at CRM at the pilot stage. This nozzle allows the addition of fine metallic powders in molten steel right before its solidification. These tests showed the possibility to implement the nozzle in an industrial stainless steel slab caster. It was observed a full melting of the injected elements (Fe and Fe-Ti), a homogeneous distribution of titanium element in slabs and a drastic improvement of the addition yield of titanium.

The targeted carbide-free bainitic TRIP microstructure have been obtained in the studied steels thanks to a specific alloy-design, following a classical hot-rolling schedule followed with a fast cooling regime and a coiling stage. Excellent balance between tensile strength and ductility are achieved and explained by transformation hardening phenomena. The sharp influence of gamma stabilizing elements (copper/nickel/manganese) on phase transformations and mechanical properties is highlighted.