Hybrid Additive Manufacturing of Forming Tools

Abstract

Additive manufacturing (AM) is widely used in the automotive industry and has been expanded to include aerospace, marine, and rail. High flexibility and the possibility of manufacturing complex parts in AM motivate the integration of additive manufacturing with classical forming technologies, which can improve tooling concepts and reduce costs. This study presents three applications of this integration. First, the possibility of successful utilization of selective laser melting for manufacturing extrusion tools with complex cooling channels and paths for thermocouples is reported, leading to significantly reduced inner die temperatures during the extrusion process. Second, sheet lamination is integrated with laser metal deposition (LMD) to manufacture deep-drawing dies. Promising results are achieved in reducing the stair step effect, which is the main challenge in sheet lamination, by LMD and following post-processing such as milling, ball burnishing, and laser polishing. The new manufacturing route shows that LMD can economically and efficiently reduce the stair step effect and omit the hardening step from the conventional manufacturing process route. Finally, LMD is used to manufacture a hot stamping punch with improved surface roughness by ball burnishing and near-surface complex cooling channels. The experimental results show that the manufactured punch has lower temperatures during hot stamping compared with the conventionally manufactured punch. This study shows the successful integration of AM processes with classical forming processes.