Selective Laser Melting for production of injection moulds

Abstract

Cell Kunststoffen at KU Leuven is cooperating with the Institute for Innovation in Sustainable Engineering (IISE) at the University of Derby, England to study the production of injection moulds with conformal cooling channels by means of selective laser melting (SLM). Because drilled cooling channels often cool inefficiently, this master's thesis aims to investigate which opportunities the design freedom of the SLM process can provide to improve cooling.

With a Renishaw AM 250 3D-printer several test channels and geometries in stainless steel (316L) were printed, using different laser power, print direction and scan spacing. The results are examined on strength, density and geometrical quality. Secondly, a test product and an injection mould to be produced with SLM are designed by means of numerical simulations and 3D-printing of prototypes.

The research proves that the SLM 3D-printing technique provides the possibility to print different shapes of conformal cooling channels in high density materials. The research delivers an overview of the properties of stainless steel (316L) produced with SLM. It also distinguishes the relevant from the irrelevant parameters. The best parameters for the production of conformal cooling channels with SLM are defined. A test product in the shape of a cup holder and its injection mould are designed. Further research can include complex conformal cooling channels within this mould to improve product quality and efficiency.