High-Strength Reaction-Sintered Silicon Carbide for Large-Scale Mirrors - Effect of Surface Oxide Layer on Bending Strength

Abstract:

Reaction-sintered silicon carbide of 800 MPa class bending strength had been newly developed. The developed silicon carbide showed good rigidity, high thermal conductivity, and high density, like a conventional sintered silicon carbide. The developed silicon carbide is one of the most attractive materials for large-scale ceramic structures because of its low processing temperature, good shape capability, low-cost processing and high purity. We had fabricated some lightweight space mirrors, such as a high-strength reaction-sintered silicon carbide mirror of 650 mm in diameter. In this study, experiments were conducted to investigate the effect of annealing on the bending strength of high-strength reaction-sintered silicon carbide. The annealing heat treatments were carried out at 1073 K, 1273 K, and 1473 K in an air atmosphere. The maximum bending strength of 1091 MPa at room temperature was achieved by the annealing heat-treatment at 1273 K for 10 h in air. We confirmed that annealing heat treatment was effective to improve the bending strength of reaction-sintered silicon carbide by inducing compressive residual stress at the surface oxide layer.

• Periodical: Advances in Science and Technology (Volume 63)
• Pages: 374-382
• DOI: https://doi.org/10.4028/www.scientific.net/AST.63.374
• Online since: October 2010
• Authors: Shoko Suyama, Yoshiyasu Itoh
• Keywords: Full Dense, Good Shape Capability, High-Strength, Light Weight, Low Processing Temperature, Mirror Substrate, Reaction Sintering, Silicon Carbide (SiC), Surface Oxide Layer

References

[1] J. Breysse, D. Castel, B. Laviron, D. Logut, M. Bougoin, Proc. of 5th ICSO, Toulouse, S5 (2004).

DOI: 10.1117/12.2552134

[2] M. Bougoin, P. Deny, Proc. of SPIE, Vol. 5494, Bellingham (2004) p.9.

[3] M. Krödel, J. Lichtsheindl, Proc. of SPIE, Vol. 5494, Bellingham (2004) p.19.

[4] M. Krödel, Proc. of SPIE, Vol. 5494, Bellingham (2004) p.297.

[5] J. S. Johnson, K. Grobsky, D. J. Bray, Proc. of SPIE, Vol. 4771 (2002) p.243.

[6] K. Tsuno, H. Irikado, K. Hamada, K. Ohno, J. Ishida, S. Suyama, Y. Itoh, N. Ebizuka, H. Eto, Y. Dai, Proc. of 5th ICSO, Toulouse, S5 (2004) p.681.

DOI: 10.1117/12.2307962

[7] K. Tsuno, H. Irikado, K. Ohno, J. Ishida, S. Suyama, Y. Itoh, N. Ebizuka, H. Eto, Y. Dai, W. Lin, T. Suzuki, H. Omori, Y. Yui, T. Kimura, Y. Tange, Proc. of SPIE, Asian-Pacific RS (2004).

DOI: 10.1117/12.580660

[8] S. Suyama, T. Kameda, Y. Itoh, Diamond and related materials, 12, (2003) p.1201.

[13] J. Korous, M. C. Chu, M. Nakatani, K. Andoh, J. Am. Ceram. Soc., 83-11(2000) p.2788.

[14] D. Sciti, S. Guicciardi, A. Bellosi, J. Euro. Ceram. Soc., 21(2001) p.621.

[15] G. Zhan, M. Mitomo, H. Tanaka, J. Am. Ceram. Soc. 83-6(2000) p.1369.

[16] Y. Itoh, M. Takahashi, H. Takano, Fusion Eng. and Design, 31(1996) p.279.