Troisiéme Conférence Européenne sur les Matériaux et les Procédés Avancés
J. Phys. IV France 03 (1993) C7-1849-C7-1852
Microplasticity of MMC. Experimental results and modellingE. MAIRE, G. LORMAND, P.F. GOBIN and R. FOUGERES
Groupe d'Etude de Métallurgie Physique et de Physique des Matériaux, URA 341 du CNRS, INSA, Bâtiment 303, 69621 Villeurbanne cedex, France
The microplastic behavior of several MMC is investigated by means of tension and compression tests. This behavior is assymetric : the proportional limit is higher in tension than in compression but the work hardening rate is higher in compression. These differences are analysed in terms of maxium of the Tresca's shear stress at the interface (proportional limit) and of the emission of dislocation loops during the cooling (work hardening rate). On another hand, a model is proposed to calculate the value of the yield stress, describing the composite as a material composed of three phases : inclusion, unaffected matrix and matrix surrounding the inclusion having a gradient in the density of the thermally induced dilocations.
© EDP Sciences 1993