Assessment of the corrosion resistance of fermanal steel coated with TiC(N)/TiNb(CN) heterostructures for use as a biomaterial

This study aims to assess corrosion resistance on multilayer coatings of [TiCN/TiNbCN]n in a physiological medium with 1, 50 and 150 bilayer periods deposited on silicon (100) and Fermanal steel (FeMnAl) substrates using R.F. reactive magnetron sputtering with a radio frequency source (13.56 MHz) and two TiC and Nb targets. The multilayers were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrochemical behavior simulated by the corporal environment was assessed using electrochemical impedance spectroscopy and Hanks solution as the electrolyte. The morphology of the attack mechanism on the coated and uncoated steel samples was characterized using SEM. The corrosion products were assessed using XRD. A notable increase was observed in corrosion resistance with the deposits of multilayer coatings on the FeMnAl alloy substrates, suggesting the spatial period effect (Λ) in the decreased degradation seenon the coatings. This result corroborates the benefits of varying the bilayer period.