The properties of a material consisting of periodical representative elements with microdefects (cylindrical micropores, flat microcracks) are investigated. An inhomogeneous mesh of linear finite elements (of square or triangular shape) condensing near the defects is used. It was shown that, to obtain a qualitative result, it is sufficient to consider an isolated representative element. The simultaneous and separate thermoelectrical and mechanical loading is considered, taking into account microdefects of material. Cooling of the metal after the action of electric current is considered. It was found that closing of the cracks under electric pulse at the first stage of loading and after it due to thermomechanical localization on the lands of cracks and meltingof the material leads to increasing the porosity. It is shown that electric current leads to weak concentrations of the temperature on the appearing circular cylindrical defects, while for planar cuts (microcracks), this concentration is very considerable. A further electric current action to the representative element with cylindrical defects does not lead to their closure due to the small concentration of temperature on round pores. This result is repeated for the sample with an ordered structure of representative elements. This phenomenon leads to an increase of the strength of the sample and to simultaneous softening of the material. In the material with the ordered structure of the defects, softening and the increase in the yield plateau takes place under a simultaneous action of electric field and tension. These results clarify the mechanism of change of material properties of the termo-electroplastic model.
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