Compression behavior of direct compounded compression molded short carbon fiber reinforced thermoplastic pyramidal lattice truss core

Lattice truss sandwich structures have a wide range of applications because of its advantages of light weight and high strength. However, current manufacturing processes are not suitable for mass production of lattice truss cores, which limits the promotion of lattice structure. This study utilizes Direct Compounded Compression Molded (DCCM) process to prepare a Short Carbon Fiber Reinforced Thermoplastic (SCFRTP) pyramidal lattice truss core within 5 min. The compression behavior and failure mode of the core with joint unconstrained and joint constrained is investigated by experiment, theoretic analysis and finite element method. The results demonstrate that the SCFRTP pyramidal truss core with joint constrained exhibits compressive specific strength (0.0512), surpassing cores of metal and resin significantly. The failure modes of the core with joint unconstrained and the core with joint constrained are joints failure and yield fracture of truss struts respectively. It is believed that the molding process can realize the mass production of lattice truss core structure and promote the wider application of the structure.