en Research Paper Research Paper The principal goal of this research is to produce a CrN/Cu multilayer coating and a CrN single-layer<br> coating and also compare their electrochemical and antibacterial behavior. In this investigation, the coatings were<br> applied to the stainless steel substrate by cathodic arc evaporation a sub-division of physical vapor deposition<br> (CAE-PVD). The present phases were characterized and the thickness of the coatings was measured using X-ray<br> diffraction (XRD) and field emission scanning electron microscopy (FE-SEM), respectively. Rockwell-C tester was<br> used to evaluate the adhesion quality. Also, to evaluate the mechanical properties of the coatings such as modulus<br> of elasticity and hardness, a nanoindentation test was used and the indentation effect and coating topography were<br> evaluated using atomic force microscopy (AFM). Studying the electrochemical behavior of the coatings was done<br> using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) tests in Ringer&#39;s<br> solution. The results of EIS tests showed that the CrN coating had higher polarization resistance in comparison to<br> the CrN/Cu coating and an increasing trend of polarization resistance related to both coatings was identified by<br> rising the time of immersion. Also, using the PDP curves, the CrN and CrN/Cu coating current densities were<br> estimated at 1.835&times;10-8 and 2.088&times;10-8, respectively. The antibacterial activity of CrN and CrN/Cu coatings was<br> evaluated by the spot-inoculation method. The results of the antibacterial test indicated that compared to CrN<br> coating, CrN/Cu coating had a better impact on the control of the bacteria growth. multilayer nanostructured coating, CrN/Cu, CAE-PVD, electrochemical impedance spectroscopy (EIS), antibacterial behavior 1 16 http://ijmse.iust.ac.ir/browse.php?a_code=A-10-488-11&slc_lang=en&sid=1 Mozhgan Hirbodjavan m.hirbod69@gmail.com 1800319475328460016463 1800319475328460016463 No Department of Materials Engineering, Bu-Ali Sina University, Hamedan, 65178-38695, Iran Arash Fattah-alhosseini arash.fattah@gmail.com 1800319475328460016464 1800319475328460016464 Yes Department of Materials Engineering, Bu-Ali Sina University, Hamedan, 65178-38695, Iran Hassan Elmkhah elmkhah@gmail.com 1800319475328460016465 1800319475328460016465 No Department of Materials Engineering, Bu-Ali Sina University, Hamedan, 65178-38695, Iran Omid Imantalab omid.imantalab@gmail.com 1800319475328460016466 1800319475328460016466 No Department of Materials Engineering, Bu-Ali Sina University, Hamedan, 65178-38695, Iran