Finite element modelling of the interphase region on the mechanical behaviour of a composite containing micrometer sized spherical particles

When a particle or filler is embedded into a polymer matrix, a third region is generated between the filler and matrix due to their chemical reaction between. This region is known as the interphase region. The properties of the interphase are affected by the material properties of the particles and the polymer matrix as well as the volume fraction of the composite. We implement the interphase mathematical model into the finite element method algorithm to investigate the effect of the interphase region on the deformation behaviour of the composite. The properties of the interphase at the matrix boundary are assumed to be smooth and continuous, while discontinuous at the particle boundary. The finite element algorithm employs Galerkin weak formulation with quadratic shape functions. The displacement, strain and stress of the composite are calculated along the radial axis originated from the centre of a particle. The finite element modelling results are presented.