Corrosion behavior of ion plated and implated films

The corrosion behavior of cathodic ion plated coatings on 52100 steel and 304 stainless steel in 0.5 N NaCl solutions was investigated. Both TiN and ZrN coatings were applied. The TiN coatings were also ion implanted with nitrogen, titanium and gold to determine the effect of ion implantation on corrosive behavior. To quantify the corrosion behavior, both potentiodynamic scans and electrochemical impedance spectroscopy were employed. It was found that ion implantation did not enhance the corrosion resistance of TiN on either 52100 steel or the 304 stainless steel. However the ZrN did protect the stainless from corrosion. It is suggested that ZrN is rendered inherently more protective by the formation of a passive layer than TiN, even with excess titanium ions from implantation. © 1992