Record number :
1410594
Title of article :
Elastic properties of porous oxide ceramics prepared using starch as a pore-forming agent
Author/Authors :
?ivcov?، نويسنده , , Zuzana and ?ern?، نويسنده , , Martin and Pabst، نويسنده , , Willi and Gregorov?، نويسنده , , Eva، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2009
Pages :
7
From page :
2765
To page :
2771
Abstract :
The elastic properties, in particular the tensile modulus (Youngʹs modulus) and Poisson ratio, of porous alumina, zirconia, and alumina–zirconia composite ceramics are studied using the resonance frequency method and the results compared with theoretical predictions. Starch is used as a pore-forming agent, so that the resulting microstructure is essentially of the matrix-inclusion type (with large bulk pores, connected by small throats when a percolation threshold is exceeded). It is found that for this type of microstructure the porosity dependence of the Youngʹs modulus is significantly below the upper Hashin–Shtrikman bound and the power-law prediction; it corresponds well, however, to a recently proposed exponential relation and to an empirical volume-weighted average of the upper and lower Hashin–Shtrikman bounds. Results for all three types of ceramics indicate that – in the porosity range considered, i.e. up to approximately 50% – the Poisson ratio depends only slightly on porosity.
Keywords :
porosity , mechanical properties , Al2O3 , ZrO2 , Starch consolidation casting , Microstructure-final
Journal title :
Journal of the European Ceramic Society
Link To Document :