Frankfurt / November 15, 2022 - November 18, 2022
Fraunhofer Joint Booth
Fraunhofer Joint Booth
The integration of RFID chips and other sensors in additively manufactured components enables digital component tracking, which simplifies logistics and makes piracy more difficult. In addition, integrated sensors can be used to measure environmental parameters such as temperature or pressure, for example in medical technology and the automotive industry. By using additive manufacturing processes, the industry can reduce work steps, but also irreversibly integrate an RFID chip into the component. In order to make in-situ integration possible, however, the laser sintering process must be modified.
Additive manufacturing using selective laser sintering (SLS) enables the production of functional components with almost unlimited geometric complexity thanks to the layer-by-layer manufacturing process. At Fraunhofer ILT, design guidelines for integrating RFID chips with reliable readout probability in plastic components made of polyamide 12 have been developed. The chips can be integrated by a geometric solution after the build process in an additional work step or in situ during the additive manufacturing of the component. For the geometric solution, barbs are used to integrate a shuttle-receiver approach, which is flush and irreversible. The in-situ integration requires a process interruption during which the powder is extracted from a cavity inserted into the part, and the RFID chip is inserted into the cavity. The build process is then continued. Fraunhofer ILT developed a reliable process for powder removal and investigated the influence of process interruption on component quality.
With the method developed at the Fraunhofer ILT, RFID chips and other sensors can be irreversibly integrated into plastic components in situ. In future projects, the process of in situ integration must be automated in order to significantly increase reproducibility and productivity.
Components subject to high levels of wear and corrosion often fail due to local surface damage. The replacement of failed components is resource intensive and recycling of metal components involves energy intensive smelting processes. Furthermore, the growing demand for increasingly scarce raw materials leads to economic dependence on importing countries and causes a significant environmental footprint due to the CO2 emissions generated in the manufacturing process.
At Fraunhofer ILT, an automated hybrid process chain for the sustainable repair of metal components is being developed. By combining the processes of turning and Extreme High-Speed Laser Material Deposition (EHLA), additive manufacturing as well as pre- and post-processing of metal components is possible in a single setup.
The EHLA process is already established within the industry in the field of surface coatings. The use of EHLA is particularly interesting for repair applications that require:
The centerpiece of the process chain is a sequence of subtractive and additive manufacturing process steps. Local material removal in the shape of a defined groove geometry is first performed at the damaged area of the defective component. Then, EHLA is applied to rebuild the volume in the pre-processed area. Subsequent subtractive machining is used to restore the original contour of the repaired component.
Automation of the process chain is achieved by using a selection of sensors in combination with user-friendly software to provide intuitive operation of the repair process. Optical sensors allow
characterization of the component surface before, during and after repair. Spatially resolved image data and height profiles are used for automated defect detection as well as for adaptive path planning for subtractive and additive process steps. The data is processed to establish the application-related circular economy and to enable predictive maintenance.
*Laser Powder Bed Fusion using AFX – Towards processing of hard-to-weld materials"
Tim Lantzsch, Fraunhofer ILT, Aachen (D)