Effect of a Thermal Annealing on the Mechanical Behaviour of Green Pm Compacts

In Powder Metallurgy the knowledge of the mechanisms governing the deformation behaviour of the material during its processing is in an initial stage due to the lack of an elasto-plastic model that could explain the mechanical behaviour, specially when the initial stage of powder die compaction is the one to be considered. For this reason geological models such as Cam-clay and Cap [1, 2, 3, 4] have initially been used to represent the plastic behaviour of the metallic particles inside the die during their compaction. The validity of these models are inevitably limited due to the different nature and, consequently, mechanical behaviour of the geological and metallic particles.