PREDICTION OF BUTT CURL DURING EM CASTING OF ALUMINIUM INGOTS

摘要

Butt curl is an undesired phenomenon that occurs in the starting phase of the casting of aluminium ingots. To gain the insight necessary to control butt curl, Hoogovens has developed a thermomechanical model that describes how an ingot deforms. In this numerical model, the casting parameters, the cooling conditions, and the alloy's properties determine the temperature changes, the stresses, and the strains inside the ingot. The model also takes into account the interaction between the butt curl and the heat transfer at the butt. Experimentally determined heat transfer coefficients and mechanical properties are included in its input. It is implemented in the finite element package MARC. A comparison with measurements carried out during an actual cast shows that the present thermomechanical model predicts the butt curl accurately enough to gain the insight necessary.