Investigation of the bending rigidity of the Inconel 625 honeycomb structure printed via direct energy deposition

The present research community is intensely interested in developing lightweight materials and structures to assist the aerospace and locomotive industries in improving their fuel efficiency and payload capacity. The present research focuses on the development of a honeycomb Inconel 625 structure via the direct metal deposition (DMD) technique to replace the existing heavyweight structures. To enable practical implementation, the two honeycomb structures were deposited, out of which one is a bare lattice, and the other was sandwiched between steel plates. The microscopic characterisation reveals the anisotropic nature and columnar grain structure. The flexural results affirm the outer performance of the sandwiched honeycomb structure over the bare lattice by an improvement of 1.5 times. The failure analysis explores the contribution of tensile stress and shear stress to the failure at the outer and mid regions of the structure. In contrast, the compressive stress at the inner region is trivial. The endorsement of the experimental results through analytical and numerical methods registers the overprediction of approximately 4 and 7%, respectively.