Effects of a Perimeter on the Post-failure Behavior of Fiber-reinforced Polymer Composite Lattices

The post-failure behavior of a fiber-reinforced polymer composite lattice was experimentally studied using a beam structure. Anisotropic topology optimization was conducted to maximize the structural stiffness and partial latticing to improve toughness. Subsequently, an infill structure was generated from the optimized results using a phase field approach. The perimeter of the two-dimensional beam structure was generated from a binary solution of the optimized results. Optimized composite lattice structures were obtained using three-dimensional printing. Three-point bending tests demonstrated that the perimeter enhanced the toughness of the composite lattice. The perimeter prevented shear band failure and improved the load-carrying capability, even after maximum loading.