Abstract
Effect of residual porosity on the flexural strength of sintered α-SiC ceramic with Al2O3 and Y2O3 as sintering aids was investigated. The flexural strength (σ)-porosity (p) behaviour of the SiC ceramics was experimentally derived based on the minimum solid area approach. Both the data from the present work and those available in the literature can be simply and well-expressed by an exponential function at a correlation coefficient as good as r2 ≃ 0.90: σ = 915exp(-9.0p)MPa The value of the exponent constant (9.0) agrees reasonably with that theoretically predicted by using the approach for an extreme of idealized oblate spheroids. The pore structure appeared to have little or no influence on the exponential σ-p behaviour, except for the presence of surface pores which act as fracture flaws leading to a major deterioration of mechanical strength compared to the predicted one.
Original language | English |
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Pages (from-to) | 229-232 |
Number of pages | 4 |
Journal | Ceramics International |
Volume | 22 |
Issue number | 3 |
DOIs | |
State | Published - 1 Jan 1996 |