V. A. Zimina, I. Yu. Smolin

FEATURES OF THE STRESS STATE OF POROUS BRITTLE MATERIALS UNDER TENSILE CONDITIONS

The paper discusses the problem of taking into account the influence of the heterogeneous structure of a material on its effective characteristics and mechanical behavior. To evaluate the effective properties and features of the stress and strain analysis of porous materials, it is proposed to use a combined method that includes experimental data (an SEM image of a porous material surface) and numerical methods of solids mechanics. Numerical simulation of the mechanical behavior of porous ceramics is performed on the basis of experimental data on its pore structure. As a result of the performed research, it is shown that this method makes it possible to determine the features of the stress and strain state of porous ceramics. The stress analysis reveals both tensile and compressive local stresses in porous ceramics mesovolumes under uniaxial tension. At the same time, the values of these local stresses exceed the mesovolume-average values by an order of magnitude.

Acknowledgment: The work was performed under the state assignment to the Institute of Strength Physics and Materials Science SB RAS, theme No. FWRW-2022-0003.

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