Deformation and Fracture of Corundum Ceramics with a Multilevel Pore Structure
- 6 Downloads
The behavior of Al2O3 ceramics having a 50% volume of pore space under compression is studied. The porous structure includes three types of pores: large porosity with an average size of 120 μm, small porosity with an average size of 2 μm, and extended porous channels (about 150 μm) formed as a result of zonal separation during sintering. It is shown that at a load of ceramics with such a multilevel pore structure, the microdamage accumulates over the entire volume of the sample. It causes decreasing the scale level of fracture from microscopic (in the case of ceramics with unimodal pore structure) to meso- and microscale (for ceramics with a multilevel pore structure). Residual deformation in such material appears at small loads of about 0.3σc due to displacements of blocks and their groups during deformation before the ultimate strength.
The authors are grateful to N.L. Savchenko for assistance in conducting experiments.
The study was conducted as part of the Program of Fundamental Scientific Research of the State Academies of Sciences for 2013–2020, section III.23 and with partial financing of from a grant of the President of the Russian Federation MK-6098.2018.8.
CONFLICT OF INTEREST
The authors declare that they do not have any conflicts of interest.