Multi‐scale modelling of fibre reinforced composites exhibiting elastoplastic deformation

Abstract

In this paper, a scale bridging approach for modelling unidirectional tungsten fibre reinforced copper (W/Cu) composite by making use of an anisotropic elastoplastic constitutive model is described. To identify the yield surface of the composite and to further validate the constitutive model, a finite element model of a unit cell (UC) of the composite is set up.The fibre distribution in the UC is random. The length of the UC in longitudinal fibre direction as well as in transverse fibre direction is 33.98 µm. The diameter of the fibres is 7 µm, the fibre volume ratio is 50 % and the total number of fibres is 10. The UC is assumed to be part of a much larger material specimen. Therefore, periodic boundary conditions are applied through equation constraints. The tungsten fibre as well as the copper matrix material is model by making use of a standard von Mises plasticity model. For the fit of the plasticity model to experimental uniaxial stress-strain data for tungsten and copper, see [1]. Displayed in Figure 1 is the meshed geometry of the unidirectional composite.