Corrosion-wear monitoring of TiN coated ASP23 steel by electrochemical noise measurements

A modified electrochemical noise (EN) technique has been applied to monitor corrosion-wear of TiN coated ASP23 steel sliding against corundum in 0.5 M H2SO4. Experimental results show that corrosion-wear mechanisms of TiN coatings depend on their substrate properties. When the substrate is active, such as ASP23 tool steel, the electrochemical noise is dominated by dissolution of the substrate at the pinholes and the hydrogen evolution all over the exposed surface.