Paper
11 October 2015 Polishability of thin electrolytic and electroless NiP layers
Author Affiliations +
Proceedings Volume 9633, Optifab 2015; 963311 (2015) https://doi.org/10.1117/12.2193749
Event: SPIE Optifab, 2015, Rochester, New York, United States
Abstract
Ultra-precise metal optics are key components of sophisticated scientific instrumentation in astronomy and space applications, covering a wide spectral range. Especially for applications in the visible or ultra-violet spectral ranges, a low roughness of the optics is required. Therefore, a polishable surface is necessary. State of the art is an amorphous nickel-phosphorus (NiP) layer, which enables several polishing techniques achieving a roughness of <1 nm RMS. Typically, these layers are approximately 30 μm to 60 μm thick. Deposited on Al6061, the bimetallic effect leads to a restricted operational temperature, caused by different coefficients of thermal expansion of Al6061 and NiP. Thinner NiP layers reduce the bimetallic effect. Hence, the possible operating temperature range. A deterministic shape correction via Magnetorheological Finishing of the substrate Al6061 leads to low shape deviations prior to the NiP deposition. This allows for depositing thin NiP-layers, which are polishable via a chemical mechanical polishing technique aiming at ultra-precise metal optics. The present article shows deposition processes and polishability of electroless and electrolytic NiP layers with thicknesses between 1 μm and 10 μm.
© (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Jan Kinast, Matthias Beier, Andreas Gebhardt, Stefan Risse, and Andreas Tünnermann "Polishability of thin electrolytic and electroless NiP layers", Proc. SPIE 9633, Optifab 2015, 963311 (11 October 2015); https://doi.org/10.1117/12.2193749
Lens.org Logo
CITATIONS
Cited by 4 scholarly publications.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Mirrors

Polishing

Surface finishing

Magnetorheological finishing

Chemical mechanical planarization

Metal optics

Aluminum

Back to Top