Abstract
Silicon Carbide (SiC) is a well-recognized material, wherein its thermo-mechanical properties, radiation and abrasion resistance make it more attractive to produce high stiff space telescope mirrors that are thermally and dimensionally stable for space applications. However, the extreme hardness of SiC renders it difficult to machine and attain high optical surface quality. In recent years, chemical vapour deposited SiC (CVD SiC) has been successfully used as telescope mirror components for ground and space applications. Indigenous manufacturing of CVD SiC blanks based on sintering and cold-isostatic approach is already established and sizes of 0.7 m of SiC blanks can be realized. However, the optical process technologies to grind and polish the large sized CVD SiC to high accuracies need to established. The aim of this present investigation is to develop an appropriate grinding and polishing procedure which is scalable for medium to large sized CVD SiC blanks to obtain high surface quality. Process trials were carried out on CVD SiC substrates using composite tools with a variety of boron carbide and diamond abrasives for grinding and polishing to arrive at an appropriate recipe for these processes. The optimal procedure established for CVD SiC processing is successfully tested for several flat and curved surfaces, including a hyperbolic conical surface. The optical metrology is done using a Zygo’s Fizeau interferometer for surface figure assessment and Bruker’s white light interferometer for surface micro-roughness evaluation. The surface figure and micro-roughness values achieved using the developed optical processes are of the order of 15 nm RMS and 10 Å RMS, respectively. Detailed microstructural characterization studies using SEM and EDX are also carried out. The results of qualification tests conducted on the CVD SiC to make it amenable for space use are also described.
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig1_HTML.png)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig2_HTML.jpg)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig3_HTML.png)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig4_HTML.png)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig5_HTML.png)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig6_HTML.png)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig7_HTML.png)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig8_HTML.png)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig9_HTML.png)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig10_HTML.png)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig11_HTML.png)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig12_HTML.png)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig13_HTML.png)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig14_HTML.png)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig15_HTML.jpg)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig16_HTML.jpg)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig17_HTML.jpg)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig18_HTML.jpg)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig19_HTML.png)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig20_HTML.jpg)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs12596-022-00925-w/MediaObjects/12596_2022_925_Fig21_HTML.png)
Similar content being viewed by others
References
P.C. Chen, C.W. Bowers et al., Advances in very lightweight composite mirror technology. Opt. Eng. 39(9), 2320–2329 (2000)
S. Guo, G. Zhang et al., Effect of materials and modelling on the design of the space-based lightweight mirror. Mater. Des. 30(1), 9–14 (2009)
S.E. Kendrick, H.P. Stahl et al., Large aperture space telescope mirror fabrication trades. Space Telesc. Instrum. Opt. Infrared Millim. 7010, 705–716 (2008)
R. Geyl, M. Cayrel, Low CTE glass, SiC & beryllium for lightweight mirror substrates. Opt. Fabr. Test. Metrol. II Proc. 5965, 461 (2005)
I.A. Palusinski, I. Ghozeil et al., Developing SiC for optical system applications. Nov. Opt. Syst. Des. Optim. VII 5524, 14 (2004)
R.A. Paquin, M.B. Magida et al., Large optics from silicon carbide. Precis. Eng. 15(1), 59 (1993)
W. Yao, Y.M. Zhang et al., Fabrication and test of reaction bond silicon carbide for optical applications. Trans. Nonferrous Met. Soc. China 16(2), 409–413 (2006)
D.E. Lencioni, D.R. Hearn et al., Advanced Land Imager calibration and performance overview. Earth Obs. Syst. IV 3750, 89 (1999)
Y. Ling, low-damage grinding/polishing of silicon carbide surfaces, SIMTech technical report precision machining group, process technology division, (PT/01/001/PM), (2001)
K. Tsuno, H. Irikado et al., New-technology silicon carbide (NT-SiC): demonstration of new material for large lightweight optical mirror, sensors. Syst. Next-Generation Satell. VIII 5659, 138 (2005)
R.S. Breidenthal, R. Galat-Skey et al., Optical surfacing of one-meter-class reaction bonded silicon carbide. Opt. Precis. Struct. 2543, 248 (1995)
W. Yao, Y.M. Zhang et al., Fabrication and test of reaction bond silicon carbide for optical applications. Trans. Nonferrous Met. Soc. China English Ed. 16, 409 (2006)
T. Korhonen, P. Keinanen et al., Polishing and testing of the 1.5 m SiC M1 mirror of the ALADIN instrument on the ADM-aeolus satellite of ESA. Opt. Fabr. Test. Metrol. III 7102, 19 (2008)
J. Robichaud, J. Green, et al. Silicon carbide optics for space situational awareness and responsive space, SSG—Tinsley, 67 (2008).
M.A. Ealey, J.A. Weliman, Polishabiity of CERAFORM sificon carbide. Adv. Mater. Opt. Precis. Struct. 2857, 78–85 (1996)
R.A.M. Keski-Kuha, J.F. Osantowski Douglas et al., Chemical vapor deposited silicon carbide mirrors for extream ultra violet applications. Opt. Eng. 36, 157 (1997)
M. Fruit, P. Antoine et al., Development of the SOFIA silicon carbide secondary mirror. Airborne Telesc. Syst. II 4857, 274 (2003)
J.S. Johnson, K.D. Grobsky et al., Rapid fabrication of lightweight silicon-carbide mirrors. Optomech. Des. Eng. 4771, 243 (2002)
S. Williams, P. Deny, Overview of the production of sintered SiC optics and optical sub-assemblies. Opt. Eng. 51, 011006 (2012)
Y. R. Mahajan, R. Johnson, Applications E. Handbook of Advanced Ceramics, ed. by R. Yashwant, Mahajan Roy Johnson, Vol 2. chapter 21, 1135 (1973)
T.D.P.V. Jalluri, S. Somashekar et al., Characterization of thermal sprayed Si on sintered SiC for space optical applications. Surf. Eng. 37(5), 1–14 (2020)
T.D.P.V. Jalluri, G.M. Gouda et al., Development and characterization of silicon dioxide clad silicon carbide optics for terrestrial and space applications. Ceram. Int. 48(1), 96–110 (2022)
J. Schlichting, Chemical vapor deposition of silicon carbide. Powder Metall. Int. 12, 196–200 (1980)
D. Malacara, Optical Shop Testing, 3rd edn. (Wiley, New Jersey NY, 2007), ISBN:9780471484042, pp. 1–45
R. Windecker, Optical roughness measurements using extended white-light interferometry. Opt. Eng. 38, 1081 (1999)
B. Sung, Y.H. Yun, SiC conversion coating prepared from silica–graphite reaction. Adv. Mater. Sci. Eng. 6383084, 1–8 (2017). https://doi.org/10.1155/2017/6383084
Acknowledgements
The authors are thankful to Mr.S.Somashekar and Mr.D.Deepak of the optics laboratory for their valuable efforts in the optical fabrication of the CVD-SSiC mirrors. Authors wish to express their sincere thanks to M/s. ARCI for supplying the CVD sintered silicon carbide blanks. The constant support and encouragement rendered by the top management of ISRO during the course of this development is gratefully acknowledged.
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary Information
Below is the link to the electronic supplementary material.
Rights and permissions
Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Jalluri, T.D.P.V., Rao, B.V., Rudraswamy, B. et al. Optical polishing and characterization of chemical vapour deposited silicon carbide mirrors for space applications. J Opt 52, 969–983 (2023). https://doi.org/10.1007/s12596-022-00925-w
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12596-022-00925-w