An Examination of Inclusions in a Quiescent Metal Furnace J. Boileau Ford Research Laboratory, USA The importance of removing impurities from molten aluminum is well known. In general, removal of impurities is a key factor in improving casting soundness and mechanical properties. One technique of removing impurities is via sedimentation, where a quiescent metal bath is used to allow the impurities to either float or settle out. This technique has proved very successful in obtaining high-quality molten aluminum for use in casting automotive components, and is the basis for processes such as the Cosworth process. As part of an annual maintenance procedure, an aluminum holding furnace was drained in preparation for examination of the brick. After the aluminum had been completely drained, a number of interesting features were observed on the walls of the furnace. Samples from these features were taken and analyzed to understand what impurities and/or chemical elements were being removed from the melt. |