Topology Optimization for Die Casting With Nonplanar Parting Surfaces and Side Dies

Abstract

Abstract. This article presents a topology optimization method for the simultaneous design of castable geometry, arbitrarily curved parting surfaces, and the inclusion of lateral side dies when necessary. An undercut-free final topology with optimal draw direction is guaranteed. Undercuts are evaluated with a density-gradient-based method, and casting dies are represented as component partitioning inspired by multicomponent topology optimization. Although previous work has discussed straight parting line optimization, this study fills a gap by introducing an arbitrarily curved parting surface naturally appearing at component interfaces. Undercut vanishes at the parting surface via a sigmoid classifier function. This new parting surface solution provides an advantage in the die casting of complex geometries. Additionally, this method incorporates lateral side dies to enable the release of cast parts with desired undercut features. Several 2D and 3D numerical examples with structural objectives are presented to validate the proposed method.