The European Space Agency (ESA) plans to explore the hot and energetic universe with a new type of telescope. The Advanced Telescope for High-Energy Astrophysics (Athena) is equipped with specially developed scientific instruments that enable spatially resolved X-ray spectroscopy and large-area, energy-resolved X-ray imaging.
Special silicon pore optics direct the X-rays to the instruments 12 meters away. The optics are supported by a high-precision optical bench. The component, which has a diameter of approximately 2700 mm and a height of 250 mm, is one of three main components of the telescope and is the subject of a joint project between ESA and Airbus Defense and Space.
Coordinated by ESA and Airbus Defence and Space, the project partners CONCAD, Fraunhofer IWU, Lach Diamant, Novelis, starrag Droop+Rein, SIEMENS, and Pokolm worked on the Athena project from October 2020 to September 2022. In addition to key research questions on milling process development and the residual stress state of the base material, holistic digitalization also played an important role. The aim was to learn from the precisely documented results during the machining of the materials and to feed the lessons learned back into the machining process immediately and iteratively.
Deep pockets had to be milled in aluminum for the optical bench. Precision and material distortion had to be taken into account. In addition, special attention was paid to the surface quality of the high-precision large component. The experts from the Pokolm TechCenter used the universal Slotworx® corner and slot milling cutter for the test series. Slotworx® milling cutters in the M series are multifunctional thanks to an extensive range of cutting inserts. The Duoplug® connection system ensured maximum concentricity and rigidity for the long overhangs.
The iterative approach in this project enables high-precision large components despite tolerance-critical residual stresses in the starting material. In addition, the digital manufacturing approach enables error-free production right from the start while reducing costs and throughput time. With data-based quality monitoring, the project also opens up a new dimension in quality monitoring. The project results can also be transferred to other industries where large components must have a precision of a few micrometers.
At the end of this highly demanding and time-critical project, all project partners were delighted with the professional teamwork.