Micromechanical interaction in two-phase iron-copper polycrystals

The plastic deformation of two-phase iron-copper polycrystals was studied e xperimentally and modelled in a semianalytical approach, taking into accoun t work-hardening behaviour, initial texture, slip processes and volume frac tions of the phases. Iron-copper polycrystals including the single-phase ma terials were produced by powder metallurgy in various compositions of iron and copper. The two-phase materials had microstructures ranging between int erpenetrating networks and matrix/inclusion type. Samples were deformed by rolling and compression at room temperature. Besides stress vs, strain duri ng compression the texture and the microhardness distribution were measured before and after the deformation. The determined quantities (stress, strai n, texture) were compared with model calculations performed with a viscopla stic self-consistent (VPSC) model from R. Lebensohn Ind C. Tome. The best p redictions of this model were found in the case of copper inclusions in an iron matrix whereas for interpenetrating networks a viscoplastic Taylor mod el was in better accordance with experiment. (C) 1999 Elsevier Science B.V. All rights reserved.