Transport Phenomena in the Production and Use of Expanded Polystyrene Patterns in Lost Foam Casting

Abstract

Experiments were carried out to study the effect of process and design variables on defect formation in the lost foam casting process. Emphasis was placed on the production of expanded polystyrene foam patterns and the use of these patterns to create desired castings. Spatial pattern density variation caused by varying the fill and canister pressure for molds with varying distance between injector and opposing wall was measured. The heat transfer coefficient and gas pressure in the gap between the metal front and the foam pattern were also measured. The study found a close correlation between the production of a uniform pattern and the production of a defect-free casting.