Chapter 13 - Laser additive manufacturing of lightweight reticulated shell structure with elevated compressive property inspired by diving bell of water spider

Abstract

Owing to reasonable stress distribution, large rigidity, and span, the reticulated shell structure is widely used in the field of aerospace industry. However, its hard-to-process nature hinders the progress of design optimization and experimental investigation. In this chapter, a series of reticulated shell structures, inspired from the diving bell of the water spider, was designed and fabricated by laser powder bed fusion (LPBF) of AlSi10Mg powder. The effects of strut diameter and strut angle on dimensional accuracy, densification behavior, and mechanical properties of LPBF-processed reticulated shell structures were investigated. All the LPBF-processed reticulated shell structures exhibited high relative density. The load-displacement curves of the reticulated shell structures exhibited a similar trend including three distinct stages of elastic stage, subsidence stage, and densification stage. The fracture mechanism of LPBF-processed reticulated shell structures with different strut diameters was revealed through a combination of finite element simulation and experimental observations. With an increase of strut diameter, the dominant fracture mechanism changed from stress-controlled to porosity-controlled fracture. The structure with a strut angle of 75 degrees exhibited the lowest stress concentration level at stress concentration points, leading to the best compressive behavior among all the designed structures.