Lattice structures are competitive to fabricate sandwich structures for their excellent mechanical properties and large internal space volume. A non-planar cross-shaped part as a regular building block has been designed and manufactured using glass fiber-reinforced thermoplastic composites. Identical cross-shaped parts can be assembled into 120-unit cell lattice structures by a mechanical interlocking method. The compressive properties of unit cell lattice structures assembled with different connections pins and sequences were investigated. Lattices with steel pins possess higher compressive modulus and strength than those with composites pins. The compressive moduli of unit cell structures are more sensitive to assembly sequence than that of multi-cell structures. When the structures change to multi-cell from unit-cell with the same assembly sequence, the compressive moduli significantly decrease. The connection between face sheets and core by the ultrasonic welding improves the compressive properties of the structures. The reversible disassembly and strong designability of lattice structures are helpful to satisfy multifunctional requirements, meanwhile realizing energy saving and emission reduction.
Effect of in-plane fiber waviness defects on the compressive properties of quasi-isotropic thermoplastic composites
