Development of 3D-printed basalt fiber reinforced thermoplastic honeycombs with enhanced compressive mechanical properties

In present work, fiber reinforced thermoplastic composite filaments consisting of polylactic acid, polycaprolactone and basalt fibers for 3D printing are developed and proposed. Mechanical test, dynamic mechanical analysis and rheology test are conducted to capture the mechanical, thermal and viscoelastic properties of 3D-printed PLA-PCL/KBF specimens. Then, circular honeycombs are fabricated using four ratios of filaments via fused deposition modeling technology, and the in-plane compressive mechanical properties are explored. The results show that circular honeycombs manufactured using PLA-PCL30/KBF filament possess superior energy absorption capacity, which is ascribed to the ductility of matrix and good interfacial matrix/fiber adhesion. Furthermore, two other honeycomb structures (hexagonal and re-entrant cell geometries) are fabricated and their compressive mechanical properties are assessed. It is revealed that the hexagonal honeycombs exhibit comparative energy absorption capacity with re-entrant ones. Therefore, the PLA-PCL/KBF composite materials are promising FDM feedstock for manufacturing honeycomb structures as energy absorbers.