A Positron Emission Particle Tracking (PEPT) Study of Inclusions in Liquid Aluminium Alloy

Abstract:

Inclusions have a detrimental effect upon casting properties but it is known empirically that a slow liquid metal flow has a beneficial effect by reducing the number of inclusions entering the casting. Positron Emission Particle Tracking (PEPT) is a method that can be used to track the path taken by radioactive particles, and can be used to follow the behaviour of inclusions as they make their way from a furnace, along the launder and into the casting. A new PEPT camera geometry was developed and used to track radioactively labelled γ-alumina particles, in the region of 600 μm size. The camera detectors were arranged radially around a launder, into which was poured 150 kg of liquid Al alloy, the radioactive particles being released at intervals during the pour. The positron camera was 0.7 m in length and 0.1 m² in cross-sectional area, and this matched the dimensions of an industrial launder. A model of inclusion behaviour in a flowing liquid Al alloy was also developed, and the Positron Imaging system described was used to validate this model.

• Periodical: Advanced Materials Research (Volume 922)
• Pages: 43-48
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.922.43
• Online since: May 2014
• Authors: D.J. Burnard*, A.J. Caden, J. Gargiuli, T. Leadbeater, D.J. Parker, William D. Griffiths
• Keywords: Aluminum (Al), Casting, Inclusion, PEPT, Positron Emission Particle Tracking, Radioactivity

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