Translator Disclaimer
15 October 2013 Melt spun aluminium alloys for moulding optics
Author Affiliations +
Proceedings Volume 8884, Optifab 2013; 88841W (2013)
Event: SPIE Optifab, 2013, Rochester, New York, United States
Melt spinning is a rapid quenching process that makes it possible to create materials with a very fine microstructure. Due to this very fine microstructure the melt spinning process is an enabler for diamond turning optics and moulds without the need of post-polishing. Using diamond turning of melt spun aluminium one can achieve ≤2 nm Rq surface roughness. Application areas are imaging and projection optics, mirrors, moulds for contact lenses and spectacles. One of the alloys that RSP produces is RSA-905. This alloy has a solid track record as a better and cheaper concept in the application of moulds for optical components such as contact lenses. The RSA-905 is a dispersion hardened amorphous-like alloy that keeps its properties when exposed to elevated temperatures (up to 380°C). This gives the material unique features for optics moulding applications. RSA-905 moulds are cheaper and better than traditional mould concepts such as copper or brass with or without NiP plating. In addition logistics can be simplified significantly: from typical weeks-months into days-week. Lifetime is typically in the range of 100.000 – 200.000 shots. For high volume production typically ranging from several 100.000 – several 1.000.000 shots, NiP plated steel moulds are typically used. By using an appropriate optical coating concept RSA-905 can be upgraded to a competitive alternative to steel in terms of price, performance and logistics. This paper presents some recent developments for improved mould performance of such concept. Hardness, wear resistance and adhesion are topics of interest and they can be applied by special coatings such as diamond-like carbon (DLC) and chromium nitride (CrN). These coatings make the aluminium alloy suitable for moulding mass production of small as well as larger optics, such as spectacle lenses.
© (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
G. Gubbels, L. Tegelaers, and R. Senden "Melt spun aluminium alloys for moulding optics", Proc. SPIE 8884, Optifab 2013, 88841W (15 October 2013);


Emerging low-cost LED thermal management materials
Proceedings of SPIE (October 20 2004)
Rapidly solidified aluminium for optical applications
Proceedings of SPIE (July 23 2008)
Diamond-turned composite mirrors
Proceedings of SPIE (December 12 2003)
Improved cryogenic aluminum mirrors
Proceedings of SPIE (September 17 1998)

Back to Top