Discrete element modeling of the microbond test of fiber reinforced composite

Discrete element method (DEM) was used to simulate the dynamic process of microbond test of fiber reinforced composites, in which the fiber and matrix were modeled as elastic and elastic-plastic materials, respectively. The interface between fiber and matrix was represented by a bilinear contact softening model. Plastic deformation and progressive cracking of the matrix were observed in the simulation with comparable similarity to the existing experimental results. The initiation and propagation of interfacial debonding were also captured by the DEM simulations, whereas it is very difficult to achieve this by other numerical methods. Vertical and inclined vises with two different vise angles were tested in the simulations. It was found that both vise geometry and vise angle had significant effect on the damages of the material, and the inclined vise was sensitive to the vise angle in terms of large variation of cutting force. The developed DEM model can also be applied to predict material damages in other more complicated fiber reinforce composite system.