Structural integration of force sensors by selective laser melting (AddKraft)

• Applicants: Professor Dr. Mario Kupnik; Professor Dr.-Ing. Matthias Weigold, since 10/2019
• Subject Area: Production Automation and Assembly Technology ; Electronic Semiconductors, Components and Circuits, Integrated Systems, Sensor Technology, Theoretical Electrical Engineering
• Term: from 2019 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 418628981

The use of selective laser melting (SLM) for additive manufacturing of integrated sensors promises substantial benefits for structural integration in different applications like light weight construction, process monitoring and medical technologies. These are free shape forming compared to conventional machining, the possibility for hermetic enclosures made of the laser-melted material and easy individualization of the sensors. While there are first realizations of SLM-capsuled actuator modules, there are no sustainable approaches for additive manufacturing of force sensors. In this project, the fundamental aptitude of additive manufactured deformation elements and encapsulations for force sensors is investigated. The manufacturing process of the elements is divided in three steps. First a part of the structural deformation element is build using the SLM process. The build process will be paused and a substrate element with an applied force sensor will be inserted in the pre-build deformation element. In the last step the build process will be resumed until the element is finished. The following research questions will be answered in this project: Is the surface roughness and the geometrical accuracy of the parts sufficient enough to integrate sensor elements? Is it possible to achieve a reproducible transfer of elongation between the deformation element and the sensor element? Is it possible to control the process based thermally induced residual stresses in the deformation element and the sensor substrate? A modified SLM process management which aims to control residual stresses and deformations acts as a base for this project. In situ process monitoring will be used to measure the thermal history of the build process and predict the residual stress and the deformation behaviour of deformation elements. To realize welding between the sensor element and the deformation body new process parameters and interface geometries will be investigated. New deformation body geometries have to be developed to exploit the advantages of the SLM process. Based on traditional deformation bodies new concepts will be developed while taking the possibilities and restrictions of the SLM process into account. After this basic research complete single- and three-dimensional sensor elements will be build and their functionality and properties will be tested in long term studies.

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Professor Dr.-Ing. Eberhard Abele, until 9/2019