Chaos in Casting: An Approach to Shrinkage Porosity

Experimental data on the effects of various factors on the incidence of shrinkage porosity in cast gold jewellery items have been accumulated in recent years. Consideration of these data leads to the conclusion that certain of these effects are unpredictable, or 'chaotic'. Possible reasons for this are presented and available experimental data are discussed and illustrated in terms of this new approach to shrinkage porosity. Interactions between the effects of different factors are illustrated and discussed as also contributing to the unpredictability of results in some instances.