Fabrication of High Strength α-SiAlON/BN Composition Ceramics by Hot Pressing

Article Preview

Abstract:

Dense Y3+-dopted α-SiAlON/BN composition ceramics was fabricated by hot pressing at 1900 °C for 60 min, and flextural strength at room and 1000 °C was investigated through three-point bending test. The results show that h-BN contribute to the densification of powder body, but h-BN have little affect on the key temperature region of sintering densification of α-SiAlON ceramics. When content of BN is lower, which didn’t affect on the phase transformation of α-SiAlON, but when content of BN is higher, besides of major phase α-SiAlON, a little of β-SiAlON was also formed. For the α-SiAlON/BN composite ceramics content of 20 wt.% h-BN, the higer flexural strength( room-temperature and 1000 °C) were abtained, the formation of β-SiAlON should be an important resonon for the higher strentgh, more important is , whose flexural strength at 1000 °C is higher 50 MPa than at room temperature, the differnce of thermal properties between SiAlON and BN should contribute to the improve of high-temperature flextural strength.

You might also be interested in these eBooks

Info:

Periodical:

Key Engineering Materials (Volumes 512-515)

Pages:

816-819

Citation:

Online since:

June 2012

Export:

Price:

Permissions CCC:

Permissions PLS:

Сopyright:

© 2012 Trans Tech Publications Ltd. All Rights Reserved

Share:

Citation:

[1] T. EkstrÖm, M. Nygren, Sialon ceramics, J. Am. Ceram. Soc. 75 (1992) 259-276.

Google Scholar

[2] G.Z. Gao, R. Metselaar, α'-Sialon ceramics: a review, Chem. Mater. 3 (1991) 242-252.

Google Scholar

[3] C.F. Liu, F. Ye, Y. Zhou, Q.C. Meng, Investigation on the microstructure of self-reinforced Nd-α-sialon ceramics, Ceram. Int. 34 (2008) 51-56.

DOI: 10.1016/j.ceramint.2006.08.016

Google Scholar

[4] C.F. Liu, F. Ye, L.M. Liu, Y. Zhou, High-temperature strength and oxidation behavior of Sc3+/Lu3+ co-doped α-sialon, Scripta Materiallia. 60 (2009) 929-932.

DOI: 10.1016/j.scriptamat.2009.01.018

Google Scholar

[5] M. Zenotchkine, R. Shuba, J.S. Kim, I.W. Chen, Effects of seeding on the microstructure and mechanical properties of α-SiAlON: I: Y-SiAlON, J. Am. Ceram. Soc. 85 (2002) 1254-1259.

DOI: 10.1111/j.1151-2916.2002.tb00254.x

Google Scholar

[6] H. Peng, Z.J. Shen, M. Nygren, The formation of in-situ reinforced microstructure in α-sialon ceramics.II. in the presence of a liquid phase, J. Mater. Res. 17 (2002) 1136-1142.

DOI: 10.1557/jmr.2002.0168

Google Scholar

[7] I.H. Shin, D.J. Kim, Growth of elongated grains in α-SiAlON ceramics, Mater. Lett. 47 (2001) 329-333.

DOI: 10.1016/s0167-577x(00)00259-7

Google Scholar

[8] C.F. Liu, X.W. Ren, F. Ye, Y. Zhou, Microstructure and mechanical properties of in-situ toughened re-α-sialon ceramics, J. Chin. Ceram Soc. 36 (2008) 1134-1139.

Google Scholar

[9] I.W. Chen, A. Rosenflanz, A tough SiAlON ceramics based on α-Si3N4 with a wisker-like microstructure, Nature. 389 (1997) 701-704.

DOI: 10.1038/39542

Google Scholar

[10] Y. Sun, Q.C. Meng, D.C. Jia, C.L. Guan, Effect of hexagonal BN on the microstructure and mechanical properties of Si3N4 ceramics, J. Mater. Process. Tech. 182 (2007) 134-138.

DOI: 10.1016/j.jmatprotec.2006.07.020

Google Scholar

[11] D.Q. Wei, Q.C. Meng, D.C. Jia, Microstructure of hot-pressed h-BN/Si3N4 ceramic composites with Y2O3–Al2O3 sintering additive, Ceram. Int. 33 (2007) 221-226.

DOI: 10.1016/j.ceramint.2005.09.004

Google Scholar

[12] L. Gao, X.H. Jin, Jingguo Li, Y.G. Li, J. Sun, BN/Si3N4 nanocomposite with high strength and good machinability, Mate. Sci. Eng. A415 (2006) 145-148.

DOI: 10.1016/j.msea.2005.09.085

Google Scholar

[13] J.M. Carrapichano, J.R. Gomes, R.F. Silva, Tribological behaviour of Si3N4-BN ceramic materials for dry sliding applications, Wear. 253 (2002) 1070-1076.

DOI: 10.1016/s0043-1648(02)00219-3

Google Scholar