A technique, which allows characterizing the local strain field over a domain
representative of the microstructure of a heterogeneous material, is described.
It is based on scanning electron microscopy, microelectrolithography, image analysis
and in situ mechanical tests. On one hand, in relation with a microstructure analysis,
it allows characterizing the different mechanisms responsible for the plasticity or
the damage of materials. On the other hand, a quantitative analysis allows comparing
and validating from a local to a global scale, the different models used for the
prediction of materials constitutive laws. Finally, the knowledge of the experimental
displacement improves seriously the results of finite element computations, by a better
determination of the boundary conditions.