Before their experimental use in astroparticle physics, surface specialist OTG Gronau brought six hexagonal stainless steel honeycombs to a high gloss for the Karlsruhe Institute of Technology (KIT). The honeycombs, which are intended for precision experiments and are made of a special steel, were contaminated during manufacture. In its search for a solution, the institute came across OTG Gronau. This was an exciting "teaching assignment" for the surface specialist: Removing burrs and smoothing the surfaces of six highly sensitive hexagonal structures with a diameter of about 1.50 meters and a honeycomb wall thickness of 200 micrometers.
"These objects have very delicate structures. This required an extremely careful approach. Any damage would have impaired their function. Electropolishing - an ablative manufacturing process without thermal or mechanical stress - is therefore very well suited," says OTG Managing Director Udo Gensowski. To ensure exactly the same results for all six honeycombs, the parameters of the electropolishing bath also had to be one hundred percent identical. The final step in the process was a final rinse over several hours with demineralized water (DI water).