Tribological behavior and biocompatibility of novel Nickel-Free stainless steel manufactured via laser powder bed fusion for biomedical applications.

[Display omitted] • The research novelty lies in evaluating the tribological and biological properties of Nickel Free Stainless Steel (NiFSS) produced through laser bed powder diffusion for metals (PBF-LB/M) additive manufacturing. • Optimized process parameters for PBF-LB/M fabrication of NiFSS resulted in samples with a relative density of 98.469% and fully ferritic microstructure in the as-built state. • Tribological experiments assessed NiFSS at constant load and sliding speed using an automated Bio-Tribometer, showing promising friction coefficients and wear rates relevant to implant applications. • NiFSS exhibited reduced Coefficient of Friction and wear rates compared to PBF-LB/M built austenitic 316L SS, attributed to its superior hardness and elastic modulus. • Biocompatibility testing with pre-osteoblastic MC3T3-E1 cells indicated better cell viability on PBF-LB/M built NiFSS compared to PBF-LB/M built 316L SS. • The present study suggests the potential of PBF-LB/M fabricated NiFSS for use in biomedical devices, particularly in joint arthroplasty applications. Due to the risk of releasing carcinogenic nickel ions from conventional 316L stainless steel under a corrosive human body environment, a new variant of steel termed nickel-free stainless steel (NiFSS) has been investigated. The present study investigates the tribological properties and biocompatibility of NiFSS manufactured via laser powder bed fusion (PBF-LB/M). The ferritic NiFSS exhibited significantly lower coefficient of friction (0.08 to 0.28) and wear rate (1.60 × 10-6 mm3/Nm to 6.60 × 10-6 mm3/Nm) compared to reported values for austenitic 316L SS, under both dry and simulated body fluid (SBF) conditions and various sliding geometries. This improvement is attributed to the superior hardness (3.394 ± 0.1340 GPa) and elastic modulus (238 ± 9.0797 GPa) of NiFSS. To assess the biocompatibility, the viability of mouse pre-osteoblastic MC3T3-E1 cells was evaluated with an Alamar Blue assay when the cells were cultured on top of PBF-LB/M built NiFSS and 316L SS samples. The results indicated that even though cell growth was most optimal on regular cell culture plastic, cell viability was better maintained on PBF-LB/M built NiFSS compared to 316L SS. Therefore, the results of the present study propose that PBF-LB/M fabricated NiFSS holds promise for application in biomedical devices for joint arthroplasty. [ABSTRACT FROM AUTHOR]