This work carries out a research about the elastic behaviour of metallic powder compacts. Cylindrical specimens with different levels of density have been submitted to uniaxial compression tests with loading and unloading cycles. The analysis of the elastic loadings shows a non-linear elasticity, which can be mathematically represented by means of a potential law. Results can be explained from two different theoretical approaches: one concerns the initial compression cycles and is based on the development of an internal field of chain forces; the other concerns advanced compression stages in which forces are distributed homogeneously among the contacts between particles.
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