Dissolution and Inhibition Mechanism of 1018 Steel in Simulated Cooling Water by Adding Phosphononoacetic Acid Compound under Two Flow Conditions

Abstract

It was monitored the dissolution process of 1018 steel in simulated cooling water during the transient and steady state conditions with time. Dissolution and growth of corrosion product layers were following using a linear flow cell and flow magnetic-induced cell. By using Electrochemical Impedance Spectroscopy, it was analyzed the dissolution and inhibition process. The growth of a layer when adding hydroxyphosphonoacetic acid, inhibits metal dissolution and it presents two different influences at the interface for impedance response. They showed that new layer forms in a simple array depending on the flow regimen and the hydroxypphosphonoacetic group added to the surface. After stabilization time of 5 hours in absence of inhibitor, continuous growth and dissolution of a layer changed the electrical characteristics for the scaling and corrosion product due to flow regimen. Electrical passive elements described qualitatively the characteristics of the layer formation due to inhibitor addition