Analyse expérimentale et modélisation numérique des couplages thermomécaniques dans les matériaux solides

In the first part, the theoretical and experimental framework used to present the thermomechanical behaviour of solid materials is briefly recalled. The main feature of the experimental approach relies on the use of thermographical techniques allowing us to deduce, from the thermal data, the distribution of heat sources arising during the mechanical transformation. In the particular case of homogeneous thermomechanical tests, an energy balance can be performed and used to derive the behavioural constitutive equations. When heterogeneities occur, the infrared images facilitate the analysis of localization mechanisms. In the second part, basic aspects of homogenization techniques are reiterated. Related to thermomechanical couplings, homogenization improves the description of the behaviour of materials and structures in which microstructural phenomena have a significant influence at the macroscopic scale. Several finite element simulations are shown concerning the thermoviscoelasticity of polymers, the thermoelasticity coupled with damage in composites, and the pseudoelastic behaviour related to the solid-solid phase change of shape memory alloys.