Abstract
Ceramic cores are used in casting processes to create complex internal shapes within the final component. The work presented here uses Computational Fluid Dynamics (CFD) analysis to predict the filling and solidification behaviour of ceramic core material during the Ceramic Injection Moulding (CIM) process in the large, complex geometries now typical of modern cores. The aim of the study is to develop a predictive capability to identify key defects in the core that might otherwise only be observed after a number of expensive manufacturing processes. Manufacturing trials using short shots have been carried out in order to validate the transient flow patterns of the paste; this has highlighted the occurrence of jetting, weld lines and flow defects that are highly dependent on the injection parameters and runner designs employed. Analysis of the modelled solidification, shear rates, stagnation points and phase migration has driven die and process optimisation in a production environment.
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Acknowledgements
The author gratefully acknowledges financial support from the Centre for Doctoral Training in Innovative Metal Processing (IMPaCT) funded by the UK Engineering and Physical Sciences Research Council (EPSRC), grant reference EP/L016206/1 and Doncasters Group.
A special thanks to Thomas Wright and the Doncasters Technical Centre and to the staff members of the University of Birmingham, in particular Richard Turner, Stuart Blackburn, John Wedderburn and Frank Biddleston.
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Cademartori, S., Humphreys, N., Gebelin, JC., Brooks, J. (2018). Implementing CFD Modelling to Address Defect Formation in Core Injection Moulding. In: Nastac, L., Pericleous, K., Sabau, A., Zhang, L., Thomas, B. (eds) CFD Modeling and Simulation in Materials Processing 2018. TMS 2018. The Minerals, Metals & Materials Series. Springer, Cham. https://doi.org/10.1007/978-3-319-72059-3_20
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