3048
Journal of the American Ceramic Society—Roberts and Garboczi
Vol. 83, No. 12
16J. Poutet, D. Manzoni, F. Hage-Chehade, C. G. Jacquin, M. J. Bouteca, J. F.
Thovert, and P. M. Adler, “The Effective Mechanical Properties of Random Porous
Media,” J. Mech. Phys. Solids, 44, 1587–620 (1996).
stresses and deformations near the high-curvature regions of the
ellipsoid.
We have compared our FEM results with several sets of
previously published experimental data. In cases where the micro-
structure of the porous ceramics roughly matches that of the
models, the agreement is very good. Because the FEM results
correspond to a known microstructure, it is possible to explain
deviations in terms of specific microstructural features. Thus,
comparison of experimental data with the three computational
results provides a useful interpretive tool. A given elastic modulus
does not correspond to a particular microstructure. Therefore, it is
important to corroborate microstructural interpretations obtained
from the elastic moduli with information about the particular
material (such as a micrograph). In the future, it would be useful
to extend this work to higher porosities and to other relevant
models (such as nonoverlapping porous spheres). It is also possible
to use statistical microstructural information obtained from two-
dimensional micrographs to generate models29 that actually mimic
physical microstructures.
17N. Ramakrishnan and V. S. Arunachalam, “Effective Elastic Moduli of Ceramic
Materials,” J. Am. Ceram. Soc., 76 [11] 2745–52 (1993).
18A. R. Boccaccini, “Comment on ‘Effective Elastic Moduli of Ceramic Materi-
als’,” J. Am. Ceram. Soc., 76 [10] 2745–52 (1994).
19R. W. Rice, “Comment on ‘Effective Elastic Moduli of Porous Ceramic
Materials’,” J. Am. Ceram. Soc., 78 [6] 1711 (1995).
20E. J. Garboczi, Internal Rept. No. 6269, National Institute of Standards and
garboczi/).
21H. L. Weissberg, “Effective Diffusion Coefficient in Porous Media,” J. Appl.
Phys., 34, 2636–39 (1963).
22A. P. Roberts and M. Teubner, “Transport Properties of Heterogeneous Materials
Derived from Gaussian Random Fields: Bounds and Simulation,” Phys. Rev. E: Stat.
Phys., Plasmas, Fluids, Relat. Interdiscip. Top., 51, 4141–54 (1995).
23A. R. Day, K. A. Snyder, E. J. Garboczi, and M. F. Thorpe, “The Elastic Moduli
of Sheet Containing Spherical Holes,” J. Mech. Phys. Solids, 40, 1031–51 (1992).
24A. V. Cherkaev, K. A. Lurie, and G. W. Milton, “Invariant Properties of the
Stress in Plane Elasticity and Equivalence Classes of Composites,” Proc. R. Soc.
London, A, 438, 519–29 (1992).
25J. B. Walsh, W. F. Brace, and A. W. England, “Effect of Porosity on
Compressibility of Glass,” J. Am. Ceram. Soc., 48 [12] 605–608 (1965).
26E. Garboczi, K. Snyder, J. Douglas, and M. Thorpe, “Geometrical Percolation
Threshold of Overlapping Ellipsoids,” Phys. Rev. E: Stat. Phys., Plasmas, Fluids,
Relat. Interdiscip. Top., 52, 819–28 (1995).
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