The Effect of Dissolved Ozone on the Corrosion Behavior of Cu-30 Ni and 304L Stainless Steel in 0.5 N NaCl Solutions
Abstract
Electrochemical experiments on the effect of dissolved ozone on the corrosion behavior of Copper-30 Nickel and 304 L stainless steel have been performed in 0.5 N Sodium chloride solutions at room temperature. The experiments performed included measurements of corrosion potential as a function of time and ozone concentrations, cyclic polarization experiments, iso-potential measurements of current densities and Auger electron spectroscopy studies of the chemical composition of the corrosion product films. The results of these experiments have shown that for both Cu-based alloy and the stainless steel, the corrosion potential exhibits a marked shift to more noble values (approx. 300 mv) for ozone concentrations less the 0.2 - 0.3 mg/l. At higher ozone concentrations the corrosion potential is virtually independent of the level of ozone dissolved in the solution. The presence of dissolved ozone resulted in a reduction in the corrosion rate for the Cu-30 Ni alloy, as measured by a significant decrease in the current density at a constant applied potential. This improvement in the corrosion resistance appears to be related to a reduction in the corrosion product film thickness and a higher fraction of oxygen to chloride in the corrosion product film. For the stainless steel, Auger electron spectroscopy indicated no appreciable differences between the passive film produced in ozonated solutions versus those in unozonated solutions. Keywords: Passivity; Pitting.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1989
- Accession Number
- ADA213804
Entities
People
- D. J. Duquette
- H. H. Lu
Organizations
- Rensselaer Polytechnic Institute