Transport phenomena in metal processing operations

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This advanced research program aims at discovering the fundamental issues limiting heat, mass, and fluid flow phenomena, during the processing and casting of liquid metals and alloys, and their transformation into sheet metal products. In the processing of liquid steel, refined metal is currently transferred from a ladle into a tundish for re-distribution into the moulds of continuous casting machines, prior to casting. It is proposed to regulate the sizes of argon bubbles within the steel passing into, and through, a tundish more closely, so as to use them to float out deleterious inclusions in the size range 1-50 microns. These sizes are impossible to remove in industrial operations. To attempt such sophisticated procedures, students need to learn complex computational fluid dynamics in order to predict the flows of metal and overlaying slags, and to use advanced monitoring equipment (sensors for temperature, species concentration, and inclusions), in order to compare these with equivalent experimental results from a full scale, water model tundish, fitted with a state of the art control system, located at McGill. Similarly, when casting steel and aluminum, it is still common to cast thick slabs of metal. Following surface conditioning (scale removal or surface machining), slabs are rolled down from 150 mm thick to a millimeter, or less! Hot rolling mills are capital intensive, and environmentally unsound. The future for metal sheet production is environmentally-green, near-net shape casting (NNSC) procedures (~2-10mm thick). These require casting molten metal onto a moving cooling substrate, so as to form a "perfect" solidified surface, free of blemishes. To accomplish this challenging goal, a unique pilot scale Horizontal Single Belt Caster (HSBC) at McGill is now available, together with an advanced, highly instrumented, simulator. Innovative fundamental work is proposed, learning exactly how the liquid metal contacts a chill surface, how the heat is transferred through an imperfect interface of peaks and valleys (at the micro-scale), and means to modify the degree of contact, depending on the alloy systems and reactions. Using state of the art instrumentation, this research aims at discovering ways to revolutionize current technologies.