Fracture toughness modelling of polymers filled with inhomogeneously distributed rigid spherical particles

Abstract

Filler particles are not homogeneously distributed in real composites consisting of polymer matrices and rigid spherical particles. In the presence of a crack, high multiaxial stresses develop in the material which are a function of the distance from the crack tip. This variation effects the stress concentration in the periphery of the inhomogeneously distributed particles. For a certain stress level closer particles are able to debond from the matrix while particle pairs with larger centre to centre distances may still be bonded to the matrix. Based on a two particle model, the debonding and matrix yielding energies were calculated. Subsequent integration over the local composite deformation results in the fracture toughness of such composites. Randomly distributed particles provide a lower fracture toughness in modelling as compared to inhomogeneoulsy distributed particles in the composite.

Keywords

• Polymer composites
• Fracture toughness
• Modeling and simulation