Lightweight core topologies have been considered as an advanced alternative to improve the overall performance of sandwich structures in bending. Designed sandwich beams containing 3D printed cores as conventional honeycomb, re‐entrant auxetic honeycomb with two positions of the cells, and chiral topologies were created with CATIA V5. The sandwich beams were manufactured from polylactic acid polymer (PLA) by fused deposition modeling (FDM) using the Ultimaker 3 Extended printer. Three‐point bending testing was conducted on sandwich beams using an Instron 8872 testing machine and following ASTM C393‐20, as to obtain the strength, bending stiffness, and energy absorption of the sandwich beams for these three designed core topologies. Comments on the cores' performance and sandwich beams response are done together with observations concerning their failure.
The impact resistance and energy absorption capability of lightweight sandwich panels mainly depend on the material properties and geometrical features of the core. To study the energy absorption capabilities of foam core sandwich panels, low velocity impact tests on panels with polyurethane or polystyrene foam core and aluminum facesheets are carried out. The results show that the sandwich panels with polystyrene foam core are potentially an appropriate candidate for energy absorption applications due to their high absorption capabilities and minimum response force transferred from the sandwich panel.
Architectured structures, particularly auxetic materials, have demonstrated encouraging applications in energy absorption as they facilitate the customization of their structural response. Specific geometries of unit cells can thus be tailored for particular needs due to recent progress in additive manufacturing techniques. This paper experimentally studies how the grading of the cell unit angle of an auxetic core in a sandwich panel affects its energy absorbing capability and structural response. 3D printed sandwich panels with uniform and graded auxetic cellular core were tested under quasistatic compression. The results show that sandwich panels with graded core exhibit much better energy absorption capabilities with higher plateau stress and densification strain. This indicates that, by appropriately controlling its geometry, auxetic structures can show further potential as core in sandwich panels for energy absorption applications.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.