Fabrication of Mullite Coating and its Oxidation Protection for Carbon Fiber Reinforced SiC Composites

Abstract:

To protect carbon fiber-reinforced SiC (C/SiC) composites against oxidation,mullite coating was prepared on C/SiC composites by dip-coating method with high solid content Al₂O₃-SiO₂ sol as raw materials. X-ray diffraction and scanning electron microscopy were employed to analyze the phase and microstructure of the coating. The results show that the as-prepared coating is SiO₂-rich, monolithic and well bonded with substrate without penetrating crack, giving rise to good oxidation-resistance. After soaked at 1400°C for 30min under static air, the coated C/SiC composites possess 87% of original flexural strength. As a result of sealing and filling of cracks and pores by viscous SiO₂ in coating, the coated C/SiC composites exhibit improved oxidation resistance at 1500°C and 1600°C. There is no change in flexural strength after oxidized at 1500°C and 1600°C for 30min, respectively. Nevertheless, the carbothermal reduction between viscous SiO₂ and free carbon in C/SiC substrate would occur obviously when oxidation temperature was elevated or oxidation time was prolonged, leading to local foaming in coating and decreasing in oxidation resistance.

• Periodical: Key Engineering Materials (Volume 697)
• Pages: 476-480
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.697.476
• Online since: July 2016
• Authors: Kuan Hong Zeng, Qing Song Ma*, Li Hui Cai
• Keywords: C/SiC Composites, Coating, Mullite, Oxidation Resistance

References

[1] L.F. Cheng, Y.D. Xu, L.T. Zhang, Sci. Eng. Comp. Mater. 10 (2002) 377~382.

[2] R.V. Hiliery, N. Bartlett, H.L. Bernstein, R.F. Davis, H. Herman, Coatings for High -Temperatures Structural Materials: Trends and Opportunities, National Academy Press, Washington, DC, (1996).

[3] Y.S. Liu, L.F. Cheng, L.T. Zhang, et al., Mater. Sci. Eng. A 466 (2007) 172–177.

[4] S.J. Wu, L.F. Cheng, L.T. Zhang, Surf. Coat. Technol. 200 (2006) 4489~4492.

[5] S.J. Wu, L.F. Cheng, L.T. Zhang, J. Inorg. Mater. 20 (2005) 251~256.

[6] Q. Zhang, L. Cheng, W. Wang, Mater. Sci. Eng. A, 473 (2008) 254~258.

[7] S.J. Wu, L.F. Cheng, L.T. Zhang, Surf. Coat. Technol. 200 (2006) 4489~4492.

[8] X.H. Zheng, Y.G. Du, J.Y. Xiao, Y.F. Lu, C.H. L, Mater. Sci. Eng. A 505 (2009) 187–190.

[9] L.F. Cheng, Y.D. Xu, L.T. Zhang, R. Gao, Carbon 39 (2001) 1127–1133.

[10] J.D. Webster, M.E. Westwood, F.H. Hayers, J. Eur. Ceram. Soc. 18 (1998) 2345~2350.

[11] M. Aparicio, A. Durán, J. Am. Ceram. Soc. 83 (2000) 1351~1355.

[12] M. Aparicio, A. Duran, Ceram. Int. 31 (2005) 631–634.

[13] X.H. Zheng, Y.G. Du, J.Y. Xiao, W.J. Zhang, L.C. Zhang, Appl. Surf. Sci. 255 (2009) 4250-4254.

[14] J. Liu, L.T. Zhang, F. Hu, J. Yang, et al., J. Eur. Ceram. Soc. 33 (2013) 433-439.

[15] J. Zhang, W. Li, S. Wang, S.X. Wang, Surf. Coat. Technol., 278 (2015) 80-86.

[16] Y.G. Wang, Y.H. Wu, L. f. Cheng, L.T. Zhang, J. Am. Ceram. Soc. (2005) 424-430.

[17] M. Pavese, P. Fino, C. Badini, Surf. Coat. Technol. 202 (2008) 2059~(2067).

[18] J. Liu, L.T. Zhang, J. Yang, J. Eur. Ceram. Soc. 32 (2012) 705~710.

[19] T. Ban, S. Hayashi, A. Yasumori, J. Eur. Ceram. Soc. 16 (1996) 127~132.

[20] C.H. Rüscher, H. Fritze, G. Borchardt, J. Am. Ceram. Soc. 1997, 80 (1997): 3225~3228.

[21] H. Fritze, J. Jojic, T. Witke, J. Eur. Ceram. Soc. 18 (1998) 2351~2364.

[22] L.S. Cividanes, T.M.B. Campos, L.A. Rodrigues, J. Sol-Gel. Sci. Tech. 55 (2010) 111~125.

[23] H.T. Liu, Q.S. Ma, W.D. Liu, Ceram. Int. 40 (2014) 7203-7212.

[24] C. Ma, H.J. Li, H. Wu, J. Mater. Sci. Technol. 29 (2013) 29~33.