This work summarizes the findings of multi-objective optimization of a gravity sand-cast steel part for which an increase of the casting yield via riser optimization was considered. This was accomplished by coupling a casting simulation software package with an optimization module. The benefits of this approach, recently adopted in foundry industry world wide and based on fully automated computer optimization, were demonstrated. First, analyses of filling and solidification of the original casting design were conducted in the standard simulation environment to determine potential flaws and inadequacies. Based on the initial assessment, the gating system was redesigned and the chills rearranged to improve the solidification pattern. After these two cases were evaluated, the adequate optimization targets and constraints were defined. One multi-objective optimization case with conflicting objectives was considered in which minimization of the riser volume together with minimization of shrinkage porosity and limitation of centerline porosity were performed.
International Journal of Metalcasting, 2010, Vol 4, Issue 4, p. 61-76