The Effects of NH4Cl and Particle Size of Al Powder in AlN Whiskers Synthesis by Direct Nitridation

Authors

Abstract

In this study, AlN whiskers were prepared in a tube furnace at 1000˚C for 1h with 500 nitrogen gas flow. Al powders with particle size of 3 μm and 45 μm and NH4Cl were used as raw materials. SEM, TEM and XRD analysis were used to characterize AlN whiskers. The results showed that the diameters of AlN whiskers would range from 140 nm to 340 nm if different amounts of NH4Cl and 3 μm Al powder were used. In the case of using NH4Cl more than 40wt%, pure AlN without any unreacted Al was formed as the final product. Using NH4Cl and Al with particle size of 45 μm led to AlN whiskers with 630 nm to 870 nm in diameter. By adding 50%wt NH4Cl, pure AlN was formed. The diameter of the whiskers was increased by increasing NH4Cl content in starting materials (about 200 nm). Also, an increase in the diameter of AlN whisker resulted from coarse Al powder. By adding NH4Cl to Al, thermodynamically spontaneous cholororination - nitridation reactions were increased in vapor phase and whiskers and pure AlN powder were produced.

Keywords

References

1. Evans, S.M., ”Identification and Characterization of
Point Defects in Aluminum Nitride and Zinc Oxide
Crystals”, Ph.D thesis, The Eberly College of Arts
and Sciences West Virginia, pp.30-36, 2008. 2. Guojin, J., Hanrui, Z., Jiong, Z., Meiling, R., Wenlan, L., Fengeying, W. and Baolin Z., “Morphologies and
Growth Mechanisms of Aluminum Nitride Whiskers
by SHS Method-part 1”, Journal of the Materials
Science, Vol. 35, pp. 57-62, 2000. 3. Zakorzhevskii, V.V., Borovinskaya, I.P. and
Sachkova, N.V., “Combustion Synthesis of
Aluminum Nitride”, Inorganic Materials, Vol. 38, pp. 1131-1140, 2002. 4. Kyung-Jae, L., Do-Hwan, A. and Young-Seod, K., “Aluminum Nitrade Whisker Forming during
Combusting Synthesis”, Journal of the American
Ceramic Society, Vol. 83, pp. 1117-1121, 2000. 5. Martin, P.M., Good, M.S., Johnston, J.W., Posakony, G.J., Bond, L.J. and Crawford S.L., “Piezoelectric
Films for 100-MHz Ultrasonic Transducers”, Thin
Solid Films, Vol. 379, pp. 253-258, 2000. 6. Revanker, V. and Goel, A., “Method for Synthesizing
Aluminum Nitride Whiskers”, United States Patent, Patent Number: 5693305, 1997. 7. Liang, J., Wang, C., Wang, Y., Jing, L. and Luan, X., ”The Influence of Surface Heat Transfer Conditions
on Thermal Shock Behavior of ZrB2–SiC–AlN
Ceramic Composites”, Scripta Materialia, Vol. 61, pp. 656-659, 2009. 8. Fu, R.,Zho, H., Chen, L. and Wu, Y., “Morphologies
and Growth Mechanisms of Aluminum Nitride
Whiskers Synthesized by Carbothermal Reduction”,
Materials Sicence and Engineering A, Vol. 266, pp. 44-51, 1999. 9. Zhou, H., Chen, H., Wu, Y., Miao,, W.G., Xi, L., ”Structure Characteristics of Whiskers Fabricated by
the Carbothermal Reduction Method”, Journal of
Materials Science, Vol. 33, pp. 4249-4253, 1998. 10. Miao, W.G., Wu, Y. and Zhou, H.,”Morphologies
and Growth Mechanisms of Aluminum Nitride
Whiskers”, Journal of Materials Science, Vol. 32, pp. 1969-1975,1997. 11.Radwa, M., Bahgat, M. and El-Geassy, A.A., “Formation of Aluminium Nitride Whiskers by
Direct Nitridation”, Journal of the European
Ceramic Society, Vol. 26, pp. 2485-2488, 2006. 12.Radwan, M. and Bahgat, M., “A Modified Direct
Nitridation Method for Formation of Nano AlN
Whiskers”, Journal of Materials Processing
Technology, Vol. 181, pp. 99-105, 2007. 13. Wang, H. and Northwood, D.O., ”Combustion
Synthesis of AlN Whiskers”, Journal of Materials
Science, Vol. 41, pp.1697-1703, 2006. 14.Bradshow, S.M. and Spicer, J.L., ”Combustion
Synthesis of Aluminum Nitride Particle and
Whiskers”, Journal of the American Ceramic
Society, Vol. 82, pp. 2293-2300, 1999. 15.Itoh, H., Morikawa, H. and Sugiyama, K., “Growth
of Aluminum Nitride Pillar Crystals by Chemical
Vapour Deposition”, Journal of Crystal growh, Vol. 94, pp. 387-391, 1989. 16. Zhou, H., Chen, H., Liu, Y. and Wu, Y., ” Growth of
Aluminum Nitride Whiskers by Sublimation
Recrystallization Method”, Journal of Materials
science,Vol. 35, pp. 471-475, 2000. 17.Jung, W.S. and Joo, H.U.,”Catalytic Growh of
Aluminum Nitrde Whiskers by a Modifierd
Carbotermal Reduction and Nitridation Method”,
Journal of Crystal Growh, Vol. 285, pp. 566-571, 2005. 18.Jung, W.S., Lee, T.J. and Min, B.K.,”Growth
Mechanism of Aluminum Nitride Whiskers Prepared
from a (Glutarato)(Hydroxo) Aluminum (III)
Complex”, Materials Letters, Vol. 57, pp. 4237- 4242, 2003. 19. Portnoi, K.I. and Gribkov, V.N., ”Growh of AlN
Whiskers during the Nitriding of Aluminum”,
Poroshkovaya Metallurgiya, Vol. 89, pp. 10-14, 1970. 20.Caceres, P.G. and Schmid, H.K.,”Morphology and
Crystallography of Aluminum Nitride Whiskers”,
Journal of the American Ceramic Society, Vol. 77 , pp. 977-983, 1994. 21. Guojin, J., Hanrui, Z., Jiong, Z., Meiling, R., Wenlan, L., Fengying, W. and Baolin, Z., ”Morphologies and
Growth Mechanisms of Aluminum Nitride Whiskers
by SHS Method- part2”, Journal of the Materials
Science, Vol. 35, pp. 63-69, 2000. 22. Wang, H., Han, J., Li, Z. and Du, S.,”Effect of
Additives on Self-Propagating High-Temperature
Synthesis of AlN”, Journal of the European Ceramic
Society, Vol. 21, pp. 2193-2198, 2001.
Journal of Advanced Materials in Engineering (Esteghlal)
Volume 34, Issue 1
May 2015
Pages 55-66

Files

Share

How to cite

Statistics

ارتقاء امنیت وب با وف ایرانی