Elucidating the impact of laser shock peening on the biocompatibility and corrosion behaviour of wire arc additive manufactured SS316L bone staples

Abstract

This study investigates the impact of Laser Shock Peening (LSP) on the biocompatibility and corrosion resistance of SS316L bone staples built using Wire Arc Additive Manufacturing (WAAM). Corrosion tests reveal substantial improvements, with a decrease in corrosion current density from 32.137 × 10− 4 mA/cm² to 3.50864 × 10− 4 mA/cm², a reduction in corrosion rate from 3.66754 × 10− 2 mm/year to 0.400415 × 10− 2 mm/year. Surface hydrophobicity evaluated through contact angle measurements, demonstrates an increase to 98.85° at the highest LSP intensity of 15.0 GW/cm², indicating improved surface properties critical for biomedical applications. The cytotoxicity analysis and surface morphology indicate that the survival, morphology, and adherence of L929 fibroblast cells improve with increasing LSP intensity