The energy absorption and bearing capacity of light-weight bio-inspired structures produced by selective laser melting

Abstract

Sandwich structures are widely used in aviation and aerospace fields because they can absorb vast energy due to their excellent continuous compression behaviors. And in this work, the light-weight bio-inspired sandwich structure of titanium alloy was designed based on cybister elytra and produced by selective laser melting (SLM). The results show that bio-inspired structures can realize the light-weight effectively by increasing the core height. The specific and ultimate flatwise compressive strengths first increase and then decrease when core height increases. The load-displacement curves of bio-inspired structures during flatwise compression consists of elastic deformation, buffer and compaction zone. Comparatively, the edgewise compression lacks buffer zone. And the bio-inspired structure has an excellent flatwise comprehensive performance when its core height is 6 mm, whose peak flatwise compressive strength and specific volume energy absorption are 84.30 MPa, 101.30 MJ/m³, respectively. The specific ultimate strength of bio-inspired structures is optimized at the core height of 4 mm on the edgewise compression tests. And the fracture of the side arc damaged area shows an obviously ductile fracture and the panel and core of the middle area are brittle fracture in the flatwise compressive tests. Finally, The ANSYS simulation results are consistent with experimental results during the whole compressions, which will provide an accurate guidance in next researches.

Keywords: Bio-inspired structure; Energy absorption-bearing capacity; Numerical simulation; Selective laser melting; Titanium alloy.