Wicking of liquid polystyrene degradation products into the pattern coating in the lost foam casting process

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Authors

External organisations

  • University of Cambridge

Abstract

Entrapment of liquid polystyrene degradation products during filling is detrimental to the quality of Aluminium Lost Foam castings. In this study, the degradation of expanded polystyrene under different heating conditions, and the ability of two pattern coatings of different permeability to absorb the partially degraded liquid polymer, was determined using gel permeation chromatography and scanning electron microscopy. It is suggested that, with the degradation of the polystyrene to a sufficiently low molecular weight liquid, significant absorption of the liquid polystyrene can occur with each coating. A number of simple plate patterns were cast in a real-time x-ray facility to determine the effect of each coating type on filling behaviour and casting quality. Similar tensile properties were found in each case, although the high permeability coating was associated with a filling velocity about twice that associated with the low permeability coating.

Details

Original languageEnglish
Title of host publicationInstitute of Cast Metals Engineers - 67th World Foundry Congress, wfc06: Casting the Future
Publication statusPublished - 2006
Event67th World Foundry Congress: Casting the Future, wfc06 - Harrogate, United Kingdom
Duration: 5 Jun 20067 Jun 2006

Conference

Conference67th World Foundry Congress: Casting the Future, wfc06
CountryUnited Kingdom
CityHarrogate
Period5/06/067/06/06

Keywords

  • Aluminium, Lost foam, Pattern coatings, Polystyrene degradation, Wicking