Evaluation of the electrochemical behavior of HVOF-sprayed alloy coatings-II

The electrochemical behavior of four different high velocity oxy fuel (HVOF) sprayed coatings has been studied. These chromium alloy coatings were intended at replacing stainless steel alloy coatings. Stainless steel coatings formed by thermal spray processes provide poor corrosion resistance. Corrosion behavior of the coatings was studied in 0.1 M HNO3 solution using gravimetric analysis, open circuit potential (OCP) measurements and potentiodynamic polarization. These results have been compared with those obtained from bulk AISI 316 stainless steel that acted as control. As per this study, sprayed nickel-chromium alloy coatings containing molybdenum appear to exhibit corrosion resistance comparable to bulk AISI 316.