The Effect of β-SiC Nanowires on the Properties of Al₂O₃ Composites

Abstract:

To investigate the effect of adding b-SiC nanowires on the properties of the Al₂O₃ matrix composites, four different amounts of SiC nanowires, 0.05, 0.1, 0.2 and 0.25 wt% were mixed with Al₂O₃ powder. All mixtures were ball-milled and dried in an oven at a temperature of 120°C. The Al₂O₃-SiC mixtures were uniaxially pressed into pellets under 5 MPa and were then isostatically cold-pressed (CIP) under a pressure of 200 MPa. Specimens (13 mm in diameter and 2.5 mm in thickness) were sintered in a tube furnace at the temperature of 1400°C for 1 h in Ar atmosphere. Physical and thermal properties of pellet composites were characterized. The bar shape specimens with dimension of 3 mm x 4 mm x 35 mm were prepared for four-point bending test. The relationship between thermal conductivity and flexural strength versus grain connection of composites have been investigated. The results showed that the composites with adding SiC nanowires at 0.05-0.2 wt% possessed lower thermal conductivity than those monolithic Al₂O₃ specimens. However, the thermal conductivity of the composite specimens with 0.25 wt% SiC nanowires became higher than those of monolithic Al₂O₃ specimens. The flexural strengths of the composites gradually decreased with the increasing amount of SiC nanowires.

• Periodical: Key Engineering Materials (Volume 690)
• Pages: 240-245
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.690.240
• Online since: May 2016
• Authors: Wasana Khongwong*, Chumphol Busabok
• Keywords: Al₂O₃ Matrix Composite, Thermal Conductivity, β-SiC Nanowires

References

[1] L. Wang, H. Wada, and L.F. Allard, Synthesis and characterization of SiC whiskers, J. Mater. Res. 7 (1992) 148-163.

DOI: 10.1557/jmr.1992.0148

[2] M. Bhatnagar, and B.J. Baliga, Comparison of 6H-SiC, 3C-SiC, and Si for power devices, IEEE Trans. Electron Devices. 40 (1993) 645-655.

DOI: 10.1109/16.199372

[3] A. Fisher, B. Schroter, and W. Richter, Low-temperature growth of SiC thin films on Si and 6H–SiC by solid-source molecular beam epitaxy, Appl. Phys. Lett. 66 (1995) 3182-3184.

DOI: 10.1063/1.113716

[4] N.H. Macmillan, Review: The theoretical strength of solids, J. Mater. Sci. 7 (1972) 239-254.

[5] E.W. Wong, P.E. Sheehan, and C.M. Lieber, Nanobeam Mechanics: Elasticity, Strength and Toughness of Nanorods and Nanotubes, Science. 277 (1997) 1971-(1975).

DOI: 10.1126/science.277.5334.1971

[6] G. Shen, D. Chen, K. Tang, Y.T. Qian, and S. Zhang, Silicon carbide hollow nanospheres, nanowires and coaxial nanowires, Chem. Phys. Lett. 375 (2003) 177-184.

DOI: 10.1016/s0009-2614(03)00877-7

[7] W. Khongwong, M. Imai, K. Yoshida and T. Yano, Synthesis of b-SiC/SiO2 Core-Shell Nanowires by Simple Thermal Evaporation, J. Ceram. Soc. Japan. 117.

DOI: 10.2109/jcersj2.117.194

[2] (2009) 194-197.

[8] W. Khongwong, M. Imai, K. Yoshida and T. Yano, Influence of Raw Powder Size, Reaction Temperature, and Soaking Time on Synthesis of SiC/SiO2 Coaxial Nanowires via Thermal Evaporation, J. Ceram. Soc. Japan. 117.

DOI: 10.2109/jcersj2.117.439

[4] (2009) 439-444.

[9] W.Y. Yang, H.Z. Miao, Z.P. Xie, L.G. Zhang and L.N. An, Synthesis of silicon carbide nanorods by catalyst-assisted pyrolysis of polymeric precursor, Chem. Phys. Lett. 383 (2004) 441-444.

DOI: 10.1016/j.cplett.2003.11.031

[10] Y. Ryu, Y. Tak and K. Yong, Direct growth of core-shell SiC-SiO2 nanowires and field emission characteristics, Nanotechnology, 16 (2005) S370-S374.

DOI: 10.1088/0957-4484/16/7/009

[11] W. Khongwong, K. Yoshida and T. Yano, Simple Approach to Fabricate SiC-SiO2 Composite Nanowires and Their Oxidation Resistance, Mater. Sci. Eng. B. 173 (2010)117-121.

DOI: 10.1016/j.mseb.2010.01.042

[12] R. Morrell, Handbook of Properties of Technical and Engineering Ceramics: Part 1 An Introduction for the Engineer and Designer, HMSO, London, (1985).