Alumina stress-strain curve

Figure 8.88 Indentation stress-strain curve for polycrystalline alumina. (Adapted from Guiberteau et al., 1994, reproduced courtesy of The American Ceramic Society, Westerville, OH.)...

Serrated stress-strain curves, similar to those occurring in metals, have also been observed in ceramics. Such stress-strain curves are shown in schematic Fig. 4.47 and experimentally observed serrated curves in alumina are illustrated in Figs. 4.48 and 4.49, formed during deformation at two temperatures and at the... 

Fig. 5.13 Stress-strain curves for alumina. Strain hardening in pure alumina and magnesia-doped alumina is due to dynamic grain growth. The eventual decrease in stress in pure alumina is a result of cavitation. Note that alumina with 2 % liquid was tested at a lower temperature [3]. With kind permission of John Wiley and Sons...

Figure 8.38 The effect of matrix composition on the stress-strain curves of AR-GRC composites containing 5% by weight fibres, after ageing in natural environment (after Majumdar [17]). (a) Portland cement (b) alumina cement (c) supersulfated cement (d) Portland + 40%flyash (e) polymer modified cement.

Examples of compressive and flexural stress-strain curves for a 60% alumina refractory measured at various temperatures are shown in Figures 11 and 12. 

The strain-time creep curves of alumina based fibers exhibit a steady state (or secondary) e-t linear domain, the corresponding strain rate, e, depending on the applied stress, a the grain size, a and the test temperature, T, according to the Dorn equation. 

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