Growth Defects and Chromium Content Loss during the Deposition of Stainless Steel by CAE-PVD and Its Effect on the Corrosion and Passivation Behavior of the Coating

Abstract

In the present study, the effects of growth defects and chromium content loss on the degradation of corrosion and passivation of cathodic arc evaporation (CAE-PVD) of stainless steel coating were investigated in 2 M sulphuric acid solution. EDS analysis indicated that the micro-particles were obtained during the coating growth. In addition, it was detected that the growth defects had poor adhesion to the coating matrix and in the open circuit potential (OCP), they were detached from the coating, providing appropriate conditions for the penetration of the solution. In addition, loss of chromium during evaporation was found to be detrimental to the passivation of the stainless steel coating and the formation of a porous oxide layer. The average percent of the main elements of the coating, according to EDS area analysis, was Fe-13Cr-6Ni. Moreover, the lower semicircle diameter of the coating in electrochemical impedance spectroscopy (EIS) measurements revealed the lower polarization resistance of it, in comparison to that of the bulk 304 stainless steel.