Transport phenomena in metal processing operations

这一高级研究计划旨在发现在液态金属和合金的加工和铸造过程中限制热、质量和流体流动现象的根本问题，以及它们转化为金属薄板产品的过程。在钢水处理中，精炼金属目前从钢包转移到中间包，然后在浇注之前再分配到连铸机的模具中。建议对进入和通过中间包的钢中的气泡尺寸进行更紧密的调节，以便利用它们漂浮出1-50微米范围内的有害夹杂物。这些尺寸在工业操作中是不可能去除的。为了尝试这种复杂的程序，学生需要学习复杂的计算流体力学，以便预测金属和熔渣的流动，并使用先进的监测设备(温度、物种浓度和夹杂物传感器)，以便将这些结果与位于McGill的全尺寸水模型中间包的等效实验结果进行比较，该中间包配备了最先进的控制系统。同样，在浇铸钢和铝时，浇铸厚厚的金属板仍然很常见。在表面处理(除垢或表面加工)之后，板材从150毫米厚压下到一毫米，甚至更少！热轧厂是资本密集型的，而且不环保。金属板生产的未来是环保的近净成形(NNSC)工艺(厚度约2-10 mm)。这需要将熔化的金属浇铸到移动的冷却基板上，以便形成没有瑕疵的“完美”凝固表面。为了实现这一具有挑战性的目标，麦吉尔的独一无二的中试规模水平单带连铸机(HSBC)现已上市，并配备了先进的、高度仪表化的模拟器。提出了创新的基础工作，学习了液态金属如何与冷表面接触，热量如何通过峰和谷的不完美界面传递(在微观尺度上)，以及根据合金系统和反应修改接触程度的方法。使用最先进的仪器，这项研究旨在发现方法，以革命性的现有技术。

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.