Functionalization of additively manufactured press hardening dies by roller burnishing

• Applicant: Professor Yannis Korkolis, Ph.D.
• Subject Area: Primary Shaping and Reshaping Technology, Additive Manufacturing
• Term: since 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 417202720

Für die Fertigung von Presshärtewerkzeugen mittels einer Kombination aus additivem For the manufacturing of press hardening tools by means of a combination of additive manufacturing processes (direct energy depostion and selective laser melting) and ball burnishing of the contacting surface, open questions regarding the quantitative analytical description of the interactions of the two manufacturing processes are to be addressed in this research project. Derived from this, the aim is the transferability of design principles for arbitrary product geometries with locally strongly varying properties, e.g. with regard to hardness and thickness. Explicitly, the influence of surface texturing on heat transfer and pressure distribution, and thus ultimately the local product properties, is to be analyzed. Comparable investigations concern the position and location of internal cooling channels, but also potentially heat-accumulating pockets. These will be considered not only in terms of their influence on the thermal component history, but also in terms of the structural integrity of themselves under different loading conditions. The aforementioned analyses additionally consider fundamental, manufacturing restrictions of additive manufacturing. For example, it is known that for laser powder cladding the minimum achievable cooling channel geometries (size and path radius) are significantly higher than those of selective laser melting. Consequently, a novel combination of these two processes for tool manufacturing is aimed at, which combines the processes in the best possible way, taking into account resource-saving manufacturing, depending on the requirement profile of the component. The aspects described are analyzed continuously and iteratively, since there are strong interactions between the individual functionalization approaches (internally through cooling channels and pockets, and externally through texturing). Based on the findings, a converging model is aimed at, which includes both the component properties and the manufacturing requirements and restrictions derived from them. This research thus forms the basis for the design of press hardening tools for the realization of partial press hardening on the tool side.

• DFG Programme: Research Grants
• Co-Investigators: Dr.-Ing. Marlon Hahn; Professor Dr.-Ing. A. Erman Tekkaya; Dr.-Ing. Heinrich Traphöner