Numerical study of mechanical behavior of ceramic composites under compression loading in the framework of movable cellular automaton method

Movable cellular automaton method was used for investigating the mechanical behavior of ceramic composites under uniaxial compression. A 2D numerical model of ceramic composites based on oxides of zirconium and aluminum with different structural parameters was developed using the SEM images of micro-sections of a real composite. The influence of such structural parameters as the geometrical dimensions of layers, inclusions, and their spatial distribution in the sample, the volume content of the composite components and their mechanical properties (as well as the amount of zirconium dioxide that underwent the phase transformation) on the fracture, strength, deformation and dissipative properties was investigated

On the dependence of effective mechanical properties of ceramics on partial concentrations of different size pores in its structure

In the framework of the movable cellular automata method we have developed a plane/2D model of mechanical behavior of brittle porous material under shear loading. The work considers the material characterized by a function of pore size distribution with two maxima. Based on simulation results, the authors proposed the analytical estimation of the dependence of strength and elastic properties of the material on its total porosity and partial porosities that correspond to the pores with different sizes

On the dependence of effective mechanical properties of ceramics on partial concentrations of different size pores in its structure

In the framework of the movable cellular automata method we have developed a plane/2D model of mechanical behavior of brittle porous material under shear loading. The work considers the material characterized by a function of pore size distribution with two maxima. Based on simulation results, the authors proposed the analytical estimation of the dependence of strength and elastic properties of the material on its total porosity and partial porosities that correspond to the pores with different sizes

3D modeling of the mechanical behavior of ceramics with pores of different size

Movable cellular automaton method was used for simulating uniaxial compression of 3D porous ceramic samples. Pores were considered explicitly by removing randomly selected automata from the original FCC packing. Distribution of pores in space, their size and the total fraction were varied. It is shown that the relation between mechanical properties of the material and its porosity significantly depends on the pore size. Thus, value of the elastic modulus of the samples with large pores is greater than that of the samples with small pores by average value of 3%-16%. Strength value of the samples with large pores is less than that of the samples with small pores by average value of 12% up to the porosity of 0.55, and then becomes to be greater. When the samples contain small and large pores there is a maximum of mechanical properties at ratio of volumes of large and small pores of about 0.75

Brittle porous material mesovolume structure models and simulation of their mechanical properties

To study the mechanical response of brittle porous materials at mesoscale, porous samples were generated and their deformation was numerically modelled. Two types of pore space morphology such as overlapping spherical pores and overlapping spherical solids were explicitly considered. For deformation modelling, an evolutionary approach including the nonlinear constitutive equations used to describe damage accumulation and its impact on the degradation of the solid frame strength properties was applied. The numerical results have shown that an average stress-strain diagram is sensitive to pore morphology as well as porosity

INVESTIGATION ON LOCALIZATION OF DEFORMATION OF MATERIALS ON MESOLEVEL BY NUMERICAL MODELLING METHODS

The methods for designs of the localization of the plastic deformation on the macro- and mesolevels have been proposed. The model has been developed, the numerical algorithms and computer programs have been developed. The special features of generating and developing the localized plastic deformation in the structural-heterogeneous materials for different models of the media both taking internal non-compensated moments into consideration and according to the moment-free theory have been studied. The model taking the non-compensated internal moments into consideration has been realized, the processes of developing drift bands on the mesoscopic scale level have been modelled, the strong increase of the local turns and drifts in the field of the deformation localization and formation of the volumetric structural elements which can be deflected as the whole ones have been discoveredAvailable from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio