Utilization of Optimization of Internal Topology in Manufacturing of Injection Moulds by the DMLS Technology

Abstract

The present paper is focused on the issue of creating residual stresses in the manufacturing of the moulded parts for injection moulding machines using DMLS technology. Thus, fractures and cracks can cause deformations and geometric inaccuracies in the final part. Moreover, they pose a potential damage risk to the machine itself. The simulation tools for the analysis of the Direct Metal Laser Sintering (DMLS) process were used to expose the critical points of the original monolithic shaped insert in which the highest stresses during the manufacture occur. Subsequently, an alternative solution was created via the optimization of the internal topology. This solution was analysed, and in terms of strength characteristics, compared to the original model in order to ensure the proper function and durability of the manufactured part. The present study was created in cooperation with a company engaged in the production of injection moulds. The internal topology optimization of the part itself is used in combination with the appropriate orientation of the model in the workspace, unlike other research in the given field, where either the model orientation optimization or the support structure is used in this design. However, except for the mentioned reduction of residual stresses, it has a positive effect on mechanical properties, reducing material consumption and savings in time; thus, the obtained results can be applied to other methods of additive manufacturing.