The team has a long experience in the developpment of homogeneization methods which allow to link the local behavior of a polycristalin materials (i.e. heteroigeneous) at typically sub-micrometric scale and the effective behavior (i.e. average). Homogenization methods in average fields, which are very efficient numerically, are enriched or compared with complete fields computations which allow a complete description of the heterogeneity of stress and strain in grains. Our research works have allowed for example : (i) the proposition of a homogenized constitutive law for thixotropic semi-liquid alloys, (ii) the development of models for elasto-viscoplastic behaviors allowing the interpretation of cyclic tests or the relaxation phenomena observed during in situ loading diffraction experiments, (iii) the analysis of the viscoplastic behavior of minerals for extreme P, T conditions representative of the Earth's mantle.
Equivalent stress and strain distributions in a metallic matrix composite Fe-TiB2.