Resource Efficient Manufacturing of Complex Cooling Structures

The combination of additive manufacturing (LPBF) and plastic injection molding offers great benefits for functional integration and thereby the functionality of parts, components and systems. By manufacturing cooling channels as very thin-walled structures, short laser processing time is needed to produce these parts. The combination with plastic overmolding allows the mechanical loads to be absorbed, while at the same time utilizing the freedom of shape of the LPBF process. In order to prevent the structures from collapsing during overmolding or to ensure that they do not have to be very thick-walled in order to withstand the high injection pressures, the structures are closed, so that the base-powder is still contained in the structure during the overmolding. After opening the overmolded components, the powder can be extracted and reused. This technique offers great potential for high functional integration and new possibilities in terms of realizing internal cooling structures of electric traction machines. Other advantages that can be exploited are the thermally good connection due to the material bond and the possibility of local reinforcement due to the design freedom of the insert. Thanks to the injection-molded component, complex geometries can also be produced without additional unit costs.