Response of composite sandwich beams with graded lattice core

This study introduces a new idea that combining graded material and lattice core for forming the graded lattice core sandwich structures, which is based on the stitching and hot-press process. The mechanical strengths and failure mechanisms under bending load are estimated. The simple mechanical analysis is effective and accurate for estimating the performance and failure mode of the sandwich panels. In order to demonstrate sensitivity of geometric parameters on the bending behavior of graded lattice core sandwich panels, four kinds of representative graded lattice core sandwich panels were fabricated and tested to probe different failure modes. The predictions of strength compared very well with measurements investigated. The optimal designs of the graded lattice core sandwich panels were determined. Six constraint functions on failure mechanisms were considered. The optimum parameters and minimum weight were evaluated. All the designs had great difference in their load capacity-per-weight and the failure mechanisms.