Compressive Strength Of Porous Ceramics

Bodies with porosities ranging from approximately 3 to 60 by volume were prepared utilizing hydrogen peroxide to induce pore formation.

Compressive strength of porous ceramics.

Alumina for example has a tensile strength of 20 000 psi 1138 mpa while the compressive strength is 350 000 psi 2400 mpa. The compressive strength of the porous hap ceramics decreases linearly with increasing macropore size for a given total porosity. With increased porosity volume. This is consistent with the preceeding discussion on fig.

However the use of the model is limited to structures with a continuous array of unidirectional walls and where buckling is the main failure mode. In the present work porous ceramics having a large porosity of 70 were obtained. For a metal the compressive strength is near that of the tensile strength while for a ceramic the compressive strength may be 10 times the tensile strength. 4 and the corresponding expressions.

Material specific gravity sg coefficient of linear expansion α m m k maximum safe operating temperature o c. Porous ceramics with porosities of 75 vol and α si 3 n 4 matte grains α β phase ratio of 1 5 or α si 3 n 4 whiskers α β phase ratio of 0 36 were prepared by in situ nitridation of silicon powder. This work reveals that the compressive behavior of unidirectional porous ceramics can be predicted by the honeycomb out of plane model in a wide porosity range from 45 to 80. The compressive test of these porous ceramics showed that large strains of 0 2 0 3 are requisite for their fracture.

The mechanical strength was primarily influenced by the crystallinity of glass ceramics and the interfaces between the crystalline phases and the glassy matrix. Preparation and compressive strength behavior of porous ceramics with β ca po3 2 fiber skeletons ota 1997 journal of the american ceramic society wiley online library skip to article content. As such weak ceramics need to be handled with great care increasing their strength is of interest. For full table with tesnsile strength compressive strength flexural strength and modulus of elasticity rotate the screen.

Ceramics tend to be weak in tension but strong in compression. The compressive strength of porous glass ceramics firstly increased and then decreased with the sintering temperature reaching a maximal value of 1 8 mpa at 750 c. Properties of some common ceramics. Depending on the ceramic material the compressive strength can get as low as 0 16 mpa for hydroxyapatite ha ca 10 po 4 6 oh 2 at a porosity of 87.