The filling process of a low pressure die cast (LPDC) aluminium alloy (A356) wheel is being investigated at Ford Alloy Wheel Plant (AWP) in New Zealand. Until recently, attention was focused on the thermal and solidification stages of this casting process and their associated defect causing attributes. A previous publication (Singh et al.), demonstrated an 80% increase in productivity and subsequent decreases in scrap rate by optimising only the solidification phase of the casting process. The work presented in this paper shifts the focus to the metal filling stage and the effects this has on the finished product. Modeling and numerical optimisation techniques, coupled with laboratory experimentation and casting trials have been employed to quantify the relationship between inlet velocities, furnace pressures and mold filling times. The results of calibrating a 2D and 3D finite element model against experimental data have revealed adverse flow patterns of molten metal in typically defective regions of the cast product. These simulations identify some actual problematic areas within the wheel. The computationally predicted flow field is further supported with laboratory trials using a lull scale transparent die and water analog model Solutions to minimise these defects in both the design and process have been calculated and are currently being implemented at Ford Alloy Wheel Plant. Preliminary casting trials have already showed that an improved filling sequence can reduce typical defects attributable to metal flow, resulting in further improvement in casting quality.
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