Microstructure and Mechanical Properties of BN Nanotubes Reinforced Si₃N₄ Porous Composites

Abstract:

The high dielectric constant of Si₃N₄ ceramic limited its application as wave-transparent materials, thus Si₃N₄ ceramics always been prepared as porous ceramics to enhance the properties of wave transparent. While the mechanical properties would be declined in this way, so the BNNTs were used to improve the properties of the composites in this paper. The porous BNNTs/ Si₃N₄ composites were prepared by normal pressure sintering in nitrogen atmosphere. Then the effects of sintering temperature and contents of BNNTs to Si₃N₄ porous ceramics and composites were investigated. The results show that the Si₃N₄ phase was transformed to β-Si₃N₄ completely when the sintering temperature was raised to 1750°C. The BNNTs and rod-like β-Si₃N₄ guaranteed the considerable mechanical properties of the composites, and the mechanical properties increased with the increase of the sintering temperature and the addition of the BNNTs. When the sintering temperature was 1750°C and the content of BNNTs was 0.5wt.%, the porosity and density of the composite are 35% and 2.0g/cm³, respectively. While the flexural strength and the elastic modulus of the composite are 231.8MPa and 62.04GPa, respectively.

• Periodical: Materials Science Forum (Volume 816)
• Pages: 64-70
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.816.64
• Online since: April 2015
• Authors: Hai Kuan Liu, Bin Li*, Chang Rui Zhang, Si Qing Wang, Kun Liu
• Keywords: Boron Nitride Nanotubes, Composites, Porous Ceramics, Silicon Nitride

References

[1] Y. Inagaki, N. Kondo, T. Ohji, High performance porous silicon nitrides, Journal of the European Ceramic Society. 22 (2002) 2489–2494.

DOI: 10.1016/s0955-2219(02)00107-3

[2] Y. F. Shao, D. H. Jia, B. Y. Liu, Characterization of porous silicon nitride ceramics by pressureless sintering using fly ash cenosphere as a pore-forming agent, Journal of the European Ceramic Society. 29 (2009) 1529–1534.

DOI: 10.1016/j.jeurceramsoc.2008.09.012

[3] A. Dı´az, S. Hampshire, Characterization of porous silicon nitride materials produced with starch, Journal of the European Ceramic Society. 24 (2004) 413–419.

DOI: 10.1016/s0955-2219(03)00212-7

[4] F. Cheng, S. M. Kelly, S. Clark, Preparation and characterization of a supported Si3N4 membrane via a non-aqueous sol-gel process, Journal of Membrane Science. 280 (2006) 530–535.

DOI: 10.1016/j.memsci.2006.02.006

[5] I. Berlanga, R. Mas-Ballesté, F. Zamora, Carbon nanotubes growth on silicon nitride substrates, Materials Letters. 65 (2011) 1479–1481.

DOI: 10.1016/j.matlet.2011.02.046

[6] D. Lahiri, A. Hadjikhani, C. Zhang, Boron nitride nanotubes reinforced aluminum composites prepared by spark plasma sintering: Microstructure, mechanical properties and deformation behavior, Materials Science & Engineering A. 574 (2013) 149-156.

DOI: 10.1016/j.msea.2013.03.022

[7] C.L. Yeh, F.S. Wu, Y.L. Chen, Effects of ɑ- and β-Si3N4 as precursors on combustion synthesis of (ɑ+β)-SiAlON composites, Journal of Alloys and Compounds. 509 (2011) 3985–3990.

DOI: 10.1016/j.jallcom.2010.12.201

[8] X. G Li, L. T Zhang, X. W Yin, Mechanical and dielectric properties of porous Si3N4-SiC(BN) ceramic, Journal of Alloys and Compounds 490 (2010) L40–L43.

DOI: 10.1016/j.jallcom.2009.10.107

[9] M. Terrones, J. M. Romo-Herrera, E. Cruz-Silva, Pure and doped boron nitride nanotubes, Materials today. 5(2007) 30-38.

DOI: 10.1016/s1369-7021(07)70077-9

[10] C. Y Zhi, Y. Bando, C. C Tang, Boron nitride nanotubes, Materials Science and Engineering R. 70 (2010) 92–111.

DOI: 10.1016/j.mser.2010.06.004

[11] J. Q Bi, W. L Wang, Y. X. Qi, Large-scale synthesis of BN nanotubes using carbon nanotubes as template, Materials Letters. 63(2009) 1299-1302.

DOI: 10.1016/j.matlet.2009.03.002

[12] D. V Tuyen, Y. J Park, H.D. Kim, Formation of rod-like Si3N4 grains in porous SRBSN bodies using 6Y2O3-2MgO sintering additive, Ceramics International. 35 (2009) 2305–2310.

DOI: 10.1016/j.ceramint.2009.01.010

[13] T. Ohji, Microstructural design and mechanical properties of porous silicon nitride ceramics, Materials Science and Engineering A. 498 (2008) 5–11.

DOI: 10.1016/j.msea.2007.09.104

[14] W. Pabst, E. Gregorov a´, G. Tich a´, Elasticity of porous ceramics-A critical study of modulus-porosity relations, Journal of the European Ceramic Society. 26 (2006), 1085–1097.

DOI: 10.1016/j.jeurceramsoc.2005.01.041

[15] F. Ye, J. Y. Zhang, H. J. Zhang, Effect of sintering temperature on microstructure and mechanical properties of highly porous silicon nitride ceramics produce by freeze casting, Materials Science and Engineering A. 527 (2010) 6501–6504.

DOI: 10.1016/j.msea.2010.07.038