Horizontal Single Belt Casting of Thin Strips of an Advanced High Strength Steel (Fe–21%Mn–2.5%Al–2.8%Si–0.08%C wt%)

This research presents numerical modeling and experimental results on thin strips of Fe–21%Mn–2.5%Al–2.8%Si–0.08%C wt% steel, obtained using the horizontal single belt casting (HSBC) process. The free stream of the molten metal, exiting from a nozzle slot, was observed to be highly unstable and nonuniform, after interacting with a 30° inclined refractory plane of a delivery system. However, increasing the inclination of the refractory plane to 45°–60° allows the falling molten metal free stream to become much more stable and less fluctuating. In addition, the molten metal can undergo a hydraulic jump when impacting and flowing down these inclined refractory planes. These hydraulic jumps result in the generation of free surface waves, which travel further downstream. Fortunately, these instabilities are not usually detrimental to the surface quality of the casting, as they are rapidly damped, to disappear within a short distance, prior to solidification. The types and numbers of solid phases then forming for this steel, under the relevant Scheil cooling conditions, are determined using FactSage software. The surface roughness of the cast strip was evaluated using a Nanovea 3D surface profilometer. Microstructures of the cast and heat‐treated strips were determined using Optical and Electron microscopes. Producing a high‐quality steel strip during horizontal single belt casting process is possible without electromagnetic braking. By targeting 4–5 mm cast thickness, at a belt speed of ≈0.8 m s−1, surface waves generated by impingement of the exiting liquid metal stream onto an inclined refractory plane are rapidly damped, prior to final solidification of the steel strip on the moving belt.