An Integrative Experimental Approach to Design Optimization and Removal Strategies of Supporting Structures Used during L-PBF of SS316L Aortic Stents

Abstract

One of the fundamental challenges in L-PBF of filigree geometries, such as aortic stents used in biomedical applications, is the requirement for a robust yet easily removable support structure that allows each component to be successfully fabricated without distortion. To solve this challenge, an integrative experimental approach was attempted in the present study by identifying an optimal support structure design and an optimized support removal strategy for this design. The specimens were manufactured using four different support structure designs based on the geometry exposed to the laser beam during the L-PBF. Support removal procedures included sand blasting (SB), glass bead blasting (GB), and electrochemical polishing (ECP). The two best-performing designs (line and cross) were chosen due to shorter lead times and lower material consumption. As an additional factor that indicates a stable design, the breaking load requirement to remove the support structures was determined. A modified line support with a 145° included angle was shown to be the best support structure design in terms of breaking load, material consumption, and manufacturing time. All three procedures were used to ensure residue-free support removal for this modified line support design, with ECP proving to be the most effective.

Scanning Strategy Investigation for Direct Powder Bed Selective Laser Processing of Silicon Carbide Ceramic

“…Additive Manufacturing (AM) can offer highly complex parts with minor post-processing operations [9][10][11]. AM is a developing technology that can produce parts from 3D CAD models, as defined by ISO/ASTM 52900 [12].…”

Green Approach for Electropolishing Surface Treatments of Additive Manufactured Parts: A Comprehensive Review

“…They allow the production of near net-shaped objects with complex and sophisticated geometries, even with internal channels and thin-walled structures, by reducing production time and cost, with respect to conventional technologies. Just think to the stents with their filigree shape, which requires high precision [2]. The world market for AM objects is estimated to reach USD 76.16 billion, with a compound annual growth rate (CAGR) of 20.8% in 2030, according to a new report by Grand View Research, Inc.…”