Constitutive Models for compaction powders

Laburpena

The powder consolidation process under pressure has an important role for the manufacture of small and complex components. Using this technique it can be obtained the final shape. Unlike conventional mass or continuous materials, wherein the mechanical behaviour is well known, powders or aggregates of particles have a behaviour which is yet to be known or even explode. There are many studies on the mechanical behaviour of the powder during compaction. Two types of models can be distinguish, micromechanical models and continuum models. The differences between them are that micromechanical models are based on random or orderly packing of spherical particles. Continuum models analyze the change in volume of the compact, the compact is treated as a porous continuous material, and to study the rate of the material it takes into account not only the effort of the deviatoric stress but also the hydrostatic stress component. Despite this fact, there is not a widely theory accepted that explains the mechanical behaviour of the particles during the powder compaction process. This work compares different models of compaction of powders in order to define the model that best fits the behaviour of these materials. [Fuente: ResearchGate]