Abstract: (10966 Views)
The principal goal of this research is to produce a CrN/Cu multilayer coating and a CrN single-layer
coating and also compare their electrochemical and antibacterial behavior. In this investigation, the coatings were
applied to the stainless steel substrate by cathodic arc evaporation a sub-division of physical vapor deposition
(CAE-PVD). The present phases were characterized and the thickness of the coatings was measured using X-ray
diffraction (XRD) and field emission scanning electron microscopy (FE-SEM), respectively. Rockwell-C tester was
used to evaluate the adhesion quality. Also, to evaluate the mechanical properties of the coatings such as modulus
of elasticity and hardness, a nanoindentation test was used and the indentation effect and coating topography were
evaluated using atomic force microscopy (AFM). Studying the electrochemical behavior of the coatings was done
using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) tests in Ringer's
solution. The results of EIS tests showed that the CrN coating had higher polarization resistance in comparison to
the CrN/Cu coating and an increasing trend of polarization resistance related to both coatings was identified by
rising the time of immersion. Also, using the PDP curves, the CrN and CrN/Cu coating current densities were
estimated at 1.835×10-8 and 2.088×10-8, respectively. The antibacterial activity of CrN and CrN/Cu coatings was
evaluated by the spot-inoculation method. The results of the antibacterial test indicated that compared to CrN
coating, CrN/Cu coating had a better impact on the control of the bacteria growth.
Full-Text [PDF 1271 kb]
(2842 Downloads)
Highlights
CrN single-layer coating and CrN/Cu multilayer nanostructured coating were successfully applied on AISI 304 stainless steel using by CAE-PVD.
SEM images showed that in both CrN and CrN/Cu coatings there are pinholes and macro-particles from melted cathode.
Nanoindentation test showed that hardness and elastic modulus of CrN and CrN/Cu coatings were 19.5 ± 2.1, 248 ± 18, 16.1 ± 0.84, and 287 ± 3 GPa.
Polarization resistance of both coatings in the Ringer solution was improved.
Antibacterial tests showed that both coatings have antibacterial behavior and CrN/Cu coating compared to CrN coating reduces the bacterial number even more after 3 h owing to the presence of Cu.