Failure analysis of bio-inspired corrugated sandwich structures fabricated by laser powder bed fusion under three-point bending

Abstract

Corrugated sandwich structures have been widely used in aviation and aerospace industries due to their perfect mechanical properties. In our work, the theoretical derivation, experimental and finite element method (FEM) were applied to investigate the failure mechanisms and processes of bio-inspired corrugated sandwich structures (BCSS) manufactured by laser powder bed fusion (LPBF) under three-point bending. The results show that the failure maps of BCSS with different structural parameters can be obtained based on the theoretical model, and the panel buckling is the fundamental failure mode because it takes up most of the area of failure maps. Moreover, the panel buckling cannot cause the BCSS to fail, and the panel yielding or core buckling is the fatal failure mode for the structures whose initial failure mode is the panel buckling. Furthermore, the experimental and FEM results agree well with those of analytical predictions.