Influence of Coated Composite Powders on the Properties of ZrB₂-YAG-Al₂O₃ Ceramics

Abstract:

ZrB₂, YAG and Al₂O₃ are widely applied because of some excellent performances, but ZrB₂ is easily oxidized in the high-temperature air. To make the ZrB₂ ceramics obtain better oxidation resistance, high-density ZrB₂-YAG-Al₂O₃ ceramics were prepared. The influences of coated composite powders on the densification and the oxidation resistance of ZrB₂-YAG-Al₂O₃ ceramics were investigated. The 80wt%ZrB₂-YAG-Al₂O₃ multiphase ceramic materials from different composite raw materials with the spark plasma sintering technique were successfully prepared. The densification of ZrB₂-YAG-Al₂O₃ ceramics with Al₂O₃-Y₂O₃ composite powder coated is easier than that of ZrB₂-YAG-Al₂O₃ ceramics with YAG-Al₂O₃ powder mixed. The reaction temperature is lower than the 1100¡æ for synthesizing YAG powders from Al₂O₃-Y₂O₃ composite powders. The weight gain are increased with increased the oxidation temperature. B₂O₃ is reacted with Al₂O₃ to form Al₁₈B₄O₃₃, Al₁₈B₄O₃₃ is melted and coated on the surface of ceramics to form a protective layer for the oxidation resistance of ceramics at high temperature. The oxidation weight gain of ZrB₂-YAG-Al₂O₃ ceramic with Al₂O₃-Y₂O₃ composite powder coated is lower than that of ZrB₂-YAG-Al₂O₃ ceramic with YAG-Al₂O₃ powder mixed.

• Periodical: Key Engineering Materials (Volumes 602-603)
• Pages: 451-456
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.602-603.451
• Online since: March 2014
• Authors: Jie Guang Song*, Xiu Qin Wang, Fang Wang, Shi Bin Li, Gang Chang Ji
• Keywords: Densification, Oxidation Resistance, Ultra-High-Temperature Ceramics, ZrB₂

References

[1] S.M. Zhang, S. Wang, Y.L. Zhu, Fabrication of ZrB2-ZrC-based composites by reactive melt infiltration at relative low temperature, Scripta Mater. 65 (2011) 139-142.

DOI: 10.1016/j.scriptamat.2011.03.033

[2] W.M. Guo, Z.G. Yang, G.J. Zhang, Microstructural evolution of ZrB2-MoSi2 composites during heat treatment, Ceram. Int. 37 (2011) 2931-2935.

DOI: 10.1016/j.ceramint.2011.03.027

[3] J. Watts, G. Hilmas, W.G. Fahrenholtz, Measurement of thermal residual stresses in ZrB2-SiC composites, J. Eur. Ceram. Soc. 31 (2011) 1811-1820.

DOI: 10.1016/j.jeurceramsoc.2011.03.024

[4] H.J. Zhou, L. Gao, Z. Wang, S. M Dong, ZrB2-SiC oxidation protective coating on C/C Composites prepared by vapor silicon infiltration process, J. Am. Ceram. Soc. 93 (2010) 915-919.

DOI: 10.1111/j.1551-2916.2009.03481.x

[5] C.S. Li, Y. J Zhang, H. Y Gong, Preparation, microstructure and properties of yttrium aluminum garnet fibers prepared by sol-gel method, Mater. Chem. Phys. 113 (2009) 31-35.

DOI: 10.1016/j.matchemphys.2008.07.025

[6] X.P. Qin, H. Yang, G.H. Zhou, Synthesis of submicron-sized spherical Y2O3 powder for n transparent YAG ceramics, Mater. Res. Bull. 46 (2011) 170-174.

DOI: 10.1016/j.materresbull.2010.11.023