Novelis Inc. recently developed and patented a unique Direct Chill (DC) casting process known as Fusion Novelis Technology. In this process a chill bar is inserted into the DC casting mould which permits for the first time the co-casting of laminate of clad ingots. These ingots can then be rolled down into clad sheet and offer distinct advantages over traditional aluminum clad sheet processing routes (i.e. brazing and roll bonding). The research presented in this Master’s Thesis was done as part of a larger collaborative research and development project with Novelis Inc. The main objective of this research was to investigate the Novelis Fusion Technology and understand it from a scientific viewpoint. The research has been multi faceted and has included: the creation of a thermal fluid model using the commercial software package CFD to model the first the DC and then Fusion casting process, as well as the design and testing of an experimental DC and Fusion caster at the Novelis Global Technology Centre (NGTC) in Kingston, Ontario. This MASc research has been focused on performing both traditional DC (for AA6111, AA3004 and AA4045) and novel Fusion (AA3004/AA4045) casting experiments. First the series of DC casting experiments was performed. During the experiments two arrays of 5 thermocouples were embedded in the ingot during the cast to capture the thermal history of the ingot. Melt poisoning with a zinc rich alloy was also performed as an independent method of determining the sump depth and shape. Other temperature measurements during the experiment (i.e. alloy superheat, mould temperature, cooling water temperature) were done to gather meaningful data for model validation. A series of Fusion casting experiments was performed after the DC casting trials. Three successful Fusion casting trials were performed at NGTC using a lab scale caster with a 152 mm × 381 mm rectangular mould divided in half by a water cooled copper chill bar. For the Fusion casting experiments the AA3003-Core/AA4045-Clad alloy system was chosen since this alloy system has already been commercially produced using this novel technology. In addition to embedded thermocouples in the Fusion cast ingot, and other temperature measurements as for the DC casting experiments, temperature measurements of the chill bar were performed to gather information for model validation. The effect of melt poisoning as the interface of the composite ingot forms was unknown, so only the core of one experimental ingot was poisoned; this gave enough information about the depth and asymmetrical shape of the AA3003-Core sump. The Fusion cast ingots were characterized (both optically and using SEM techniques) at four distinct locations across the width of the ingot, consistent with different thermal histories at the interface and regions where good and poor interfaces were found in the solidified ingot. No clear correlation between thermal history and the quality of the interface could be found indicating that the interface formation during Fusion casting is extremely complicated and other factors such as oxide formation and wetting mechanisms of the AA4045 on the AA3004 need to be understood to gain a more in depth understanding of the conditions necessary to form a defect free interface. Comparisons of the measured thermal histories and sump depth and shape measurements to the model predictions were excellent.

A series of AlSi9Mg alloys were prepared and tested to reveal the effect of addition sequence and timing of grain refiner and eutectic modifier. AlSr10 master alloy was used as an modification reagent, and also for grain refiner AlTi5B master alloy was used. The depression at the eutectic temperature due to the addition of modifier and decrease in the amount of undercooling at the liquidus due to the presence of grain refiner were examined by the cooling curves which were obtained by the Alu-Therm instrument, which is the aluminum thermal analyzer of the Heraeus Electro-Nite. The alloys that were both modified and grain refined were subsequently poured as tensile test specimen shapes in permanent die casting mould for four times at 60 minutes time intervals, meanwhile thermal analysis of the alloys were also made. In this work the effect of grain refinement and modification agent, also the determination of the optimum time to pour after adding these agents were studied by aluminum thermal analyzer. The parameters obtained from this analyzer are compared with the microstructures / to see the effect of these agents on mechanical properties, hardness, tensile strength and percent elongation values were investigated. In this study the possibility of predicting the mechanical properties prior to casting by thermal analysis method was examined by regression analysis method. By this method relationship between thermal analysis parameters and mechanical properties was established.

Thesis (Ph.D.)--McMaster University, 2005. / Supervisor: P.S. Nicholson. Includes bibliographical references (leaves 135-157).

Thesis (Ph. D.)--Carleton University, 2004. / Includes bibliographical references (p. 123-134). Also available in electronic format on the Internet.

Thesis (M.App.Sc.) - Carleton University, 2005. / Includes bibliographical references (p. 102-108). Also available in electronic format on the Internet.

Thesis (M.App.Sc.) - Carleton University, 2006. / Includes bibliographical references (p. 110-113). Also available in electronic format on the Internet.

Thesis (Ph. D.)--Ohio State University, 2008. / Title from first page of PDF file. Includes bibliographical references (p. 169-178).

Mémoire (M.Eng.)-- Université du Québec à Chicoutimi, 1993. / Document électronique également accessible en format PDF. CaQCU

Mémoire (M.Eng.)--Université du Québec à Chicoutimi, 1996. / Document électronique également accessible en format PDF. CaQCU

Mémoire (M.Eng.)--Université du Québec à Chicoutimi, 1996. / L'abréviation "tm" dans le titre signifie une marque de commerce (Trademark). CaQCU Document électronique également accessible en format PDF. CaQCU