Overall properties of composites with physically non-linear discrete phase

The problem of constructing effective constitutive laws is solved for matri x composites with a physically non-linear discrete phase. The technique emp loyed is a variant of the self-consistent method in which interaction betwe en inclusions is described by disturbance of external field. The approach i s based on generalisation of the Eshelby's theorem. Use of a thermodynamic lime scale leads to a reduction of this problem to the solution of four lin ear integral equations. This procedure presents the possibility of applying this averaging scheme to engineering problems of materials design. As an e xample the problem of designing artificial biocomposites is discussed. The material is modelled as a two-phase matrix composite with a brittle elastic matrix and visco-plastic inclusions. Dense hydroxyapatite is considered as the matrix material and recommended properties of the plastificator are de rived under the condition that material should possess the mechanical prope rties as close to the human cortical bone as possible. The elastic constant s and the yield stress for plastificator are obtained as functions of the v olume concentration of phases. The application of the method to the design of artificial bio-composites is discussed. (C) 1999 Elsevier Science Ltd. A ll rights reserved.