Sub-micron alumina ceramics were fabricated by spark plasma sintering technique (SPS), using commercial α-Al2O3 powders as starting material and MgO as sintering-aid. The effects of sintering temperature and sintering-aid content on densification and grain growth of sub-micron alumina were systemically studied. The results show that the optimal sub-micron alumina is obtained by sintering at 1250℃ for 5min under 60MPa, doped with 0.05wt%MgO. The relative density and the average grain size are 99.8%TD and 0.68μm, respectively. Moreover, the Vickers hardness can reach 20.75GPa (HV5), and the in-line transmission (1mm thickness) in the 3-5μm mid-infrared range is measured beyond 83%. However, second phase MgAl2O4 is found in the samples doped with more than 0.1wt%MgO, resulting in a lower transmittance because of light scattering.
SHAN Meng
,
ZHOU Guo-Hong
,
WANG Shi-Wei
. Fabrication of Sub-micron Alumina by Spark Plasma Sintering[J]. Journal of Inorganic Materials, 2008
, 23(5)
: 1001
-1004
.
DOI: 10.3724/SP.J.1077.2008.01001
[1] Krell A, Blank P, Ma H, et al. J. Am. Ceram. Soc., 2003, 86 (4): 546-553.
[2] Rosenflanz A, Frey M, Endres B. Nature, 2004, 430: 761-764.
[3] Krell A, Blank P, Ma H, et al. J. Am. Ceram. Soc., 2003, 86 (1): 12-18.
[4] Godlinski D, Kuntz M, Grathwohl D. J. Am. Ceram. Soc., 2002, 85 (10): 2449-2456.
[5] Echeberria J, Tarazona J, He J Y, et al. J. Eur. Ceram. Soc., 2002, 22 (11): 1801-1809.
[6] Wang S W, Chen L D, Hirai T. J. Mater. Res., 2000, 15 (4): 982-987.
[7] Shen Z J, Johnesson M, Zhao Z, et al. J. Am. Ceram. Soc., 2002, 85 (8): 1921-1927.
[8] Zhan G D, Kuntz J, Wan J, et al. Scripta Mater., 2002, 47 (11): 737-741.
[9] Jiang D T, Hulbert D M, Anselmi-Tambruini U, et al. J. Am. Ceram. Soc., 2007, 91 (1): 151-154.
[10] Peelen J G J. Influence of MgO on the Evolution of the Microstructure of Al2O3, In: Mater. Sci. Res., Vol 10. New York, 1975. 443-453.