Abstract :
The global, intergranular and intragranular responses of a polycrystalline aggregate are investigated. It is shown that the heterogeneity of stress and strain dramatically increases from the global to the local level. Plastic deformation structures develop on a scale larger than the grain. Several types of boundary conditions are applied to polycrystalline aggregates, in order to estimate the importance of the surface effect. The results obtained are presented as contour plots on the cube, and a detailed study is performed to relate the variation obtained with the orientation of the grain and the position in the aggregate.
