Control of surface finish and mechanical properties of nitinol stents fabricated via laser powder bed fusion

This study systematically investigates how laser powder bed fusion (L-PBF) processing parameters influence the mechanical performance, surface quality, and functional behavior of nitinol stents. Using a Box–Behnken design of experiments, the authors correlated laser power, scan speed, and hatch spacing with relative density, surface roughness, phase transformation temperatures, and compressive mechanical behavior. Electropolishing significantly reduced surface roughness (up to 87%), while optimized L-PBF parameters enabled fabrication of superelastic nitinol stents with high recoverability and improved mechanical integrity, demonstrating the suitability of additive manufacturing for patient-specific cardiovascular implants.