Abstract
Oversized rare-earth dopant ions such as Y3+, Nd3+, and La3+ segregate to grain boundaries and reduce the tensile creep rate of α-Al2O3 by 2-3 orders of magnitude. It has been speculated that these dopant ions can modify the grain boundary structure in alumina by promoting the formation of special grain boundaries. If this were indeed the case, it would provide a possible explanation for the aforementioned creep rate retardation. In order to test this hypothesis, electron backscatter diffraction (EBSD) has been used to assess both the proportion of coincidence-site lattice boundaries, and the grain boundary misorientation distribution, in aluminas doped with various ions (Zr, Y, Nd, La, Nd/Zr). The results show that the grain boundary structure in alumina is not significantly altered by the addition of the above dopants, implying that the change in grain boundary chemistry is primarily responsible for the observed creep behavior.
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J. D. FRENCH, J. ZHAO, M. P. HARMER, H. M. CHAN and G. A. MILLER, J. Amer. Ceram. Soc. 77(11) (1994) 2857.
J. CHO, M. P. HARMER, H. M. CHAN, J. M. RICKMAN and A. M. THOMPSON, ibid. 80(4) (1997) 1013.
Y.-Z. LI, C. WANG, H. M. CHAN, J. M. RICKMAN, M. P. HARMER, J. M. CHABALA, K. L GAVRILOV and R. LEVI-SETTI, ibid. 82 (1999) 1497.
E. L. COURTRIGHT, Ceram. Eng. Sci. Proc. 12 (1991) 1725.
N. M. TALLAN, ibid. 12 (1991) 957.
B. O. ELFSTRÖM, 3rd Aero Days Post-Conference Proceedings, No. 2 (1998) p. 81.
C.-W. LIand W. D. KINGERY, in “Advances in Ceramics,” Vol. 10, Structure and Properties of MgO and Al2O3 Ceramics, edited by W. D. Kingery (American Ceramic Society, Columbus, OH, 1984) p. 368.
M. K. LOUDJANI, A. M. HUNTZ and R. CORTES, J. Mater. Sci. 28 (1993) 6466.
A. M. THOMPSON, K. K. SONI, H. M. CHAN, M. P. HARMER, D. B. WILLIAMS, J. M. CHABALA and R. LEVI-SETTI, J. Amer. Ceram. Soc. 80(2) (1997) 373.
J. BRULEY, J. CHO, J. C. FANG, A. M. THOMPSON, Y. Z. LI, H. M. CHAN and M. P. HARMER, ibid. 82 (1999) 2865.
J. CHO, Ph. D. thesis, Lehigh University, 1998.
H. YOSHIDA, Y. IKUHARA and T. SAKUMA, Phil. Mag. Lett. 79 (1999) 249.
H. KOKAWA, T. WATANABE and S. KARASHIMA, Phil. Mag. A 44(6) (1981) 1239.
S. LARTIGUE and L. PRIESTER, J. Amer. Ceram. Soc. 71(6) (1988) 430.
Idem., J. Physique C5-49 (1988) 451.
S. LARTIGUE-KORINEK and F. DUPAU, Acta Met. 42 (1994) 293.
D. BOUCHET, F. DUPAU, F. and S. LARTIGUEKORINEK, Microsc. Microanal. Microstruct. 4 (1993) 561.
J. CHO, H. M. CHAN, M. P. HARMER and J. M. RICKMAN, J. Amer. Ceram. Soc. 81(11) (1998) 3001.
M. A. GÜLGÜN, V. PUTLAYEV and M. RÜHLE, ibid., in press.
D. J. DINGLEY and V. RANDLE, J. Mater. Sci. 27 (1992) 4545.
S. J. WRIGHT and B. L. ADAMS, Metall. Trans. A 23 (1992) 759.
J. CHO, C. WANG, H. M. CHAN, J. M. RICKMAN and M. P. HARMER, Acta. Met. et. Mat. 47 (1999) 4197.
V. RANDLE, “Microtexture Determination and Its Applications” (The Institute of Materials, London, 1992).
H. GRIMMER, R. BONNET, S. LARTIGUE and L. PRIESTER, Phil. Mag. A 61(3) (1990) 493.
D. G. BRANDON, Acta Metall. 14 (1966) 1479.
K. SHIN and A. H. KING, in “Structure and Property Relationships for Interfaces,” edited by J. L. WALTER, A. H. KING and K. TANGRI (ASM International, 1991) p. 25. Received 14 March and accepted 4 September 2001 64
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Cho, J., Wang, CM., Chan, H.M. et al. A study of grain-boundary structure in rare-earth doped aluminas using an EBSD technique. Journal of Materials Science 37, 59–64 (2002). https://doi.org/10.1023/A:1013185506017
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DOI: https://doi.org/10.1023/A:1013185506017