Mechanical Properties of Pyramidal Lattice Sandwich CFRP Composites to Flat and Bending Loads

Abstract

In this study, by rearranging the typical pyramid lattice structure of carbon fibre reinforced polymer composites to obtain a small node distance and simplify the fabrication procedure, a new type of pyramid lattice structure is designed and fabricated using the snap-fit method. The flatwise compression and bending properties of the new pyramid lattice structure are studied experimentally. The results show that the compression failure mode of the lattice structure is truss fracture, while the bending failure mode is truss fracture and debonding between face sheets and cores. The damage distribution of the fibre and matrix in the lattice structure core is obtained via a finite element simulation, and it is found that there are differences in the ply damage with different fibre directions. In addition, the influence of the core truss length and layering direction on compression and bending properties of the structure are analysed using a finite element simulation.

Improved compressive performance of lattice truss core sandwich composites with modified Kagome topologies: An experimental and numerical study

“…This must be mentioned that achieving error in the range of 9%-35% without introducing imperfection for LTCSC panels made of yarns can be regarded as quite satisfactory in comparison with similar studies. 11,14,16 Without the incorporation of imperfection, error as high as one order of magnitude was reported by other literature; 11,14,16 however, they reduced the error to 5%-50% with the inclusion of imperfection. According to the 3-D Hashin failure criterion, FC failure was the first damage mode that initiated the degradation of material properties in the composite strut.…”

“…They compared their proposed homogenization method results with experimental results and found agreeable consistency. Yang et al 16 studied the compressive and bending properties of LTCSCs with pyramidal topology, experimentally and numerically. In comparison with other studies, there was a moderate difference (about 25% to 50%) between the predicted compressive stiffness of the LTCSC and experimental data.…”