Presentation details
» Aspects of Glass Foils Thermal Forming for X-ray Telescopes Mirrors
Presentation duration: 20 minutes
Presenter: Martin Mika
We have studied the precise thermal forming of glass foils with the aim to develop a low-cost technology suitable for the mass-producing of thin X-ray optics shells meeting the requirements of the future large X-ray telescopes. We used commercially available thin glass foils with an excellent micro-roughness of few 0.1 nm. Our special composite mandrels with surfaces avoiding the sticking of glass foils served as the support for the foils during the slumping process. In some experiments additional force was applied on the top surface of the samples. To optimize the process we varied both temperature and time of heat-treatment following our experiment design. We measured the shape and surface quality (the waviness and micro-roughness) of the micro-sheets employing the Tylor-Hobson mechanical profilometry, the optical interferometry (ZYGO), and the Atomic Force Microscopy (AFM) analysis. Knowing the response surfaces of the measured properties, we were able to determine the time-temperature area where we achieved the best surface quality with the micro-roughness below 0.3 nm. Within this area the shape of the foils was dependent on the soaking time and temperature; hence, we are able to modify the shape by controlling these two parameters keeping the high surface quality. This way we can fabricate foils of various shapes using just one mandrel. We suppose that this approach can substantially reduce the number of expensive mandrels needed for the production of shells with various shapes. We expect that besides lowering costs this technology can also significantly speed up the manufacture of X-ray telescopes mirrors.
Authors:- Martin Míka
- Martina Landová
- Veronika Semencová
- René Hudec
- Adolf Inneman
- Ladislav Pína
- Michaela Skulinová
- Libor Švéda
- Vlastimil Brožek
- Jan Šik