Experimental system for electrochemical studies of aqueous corrosion at temperatures above 300°C

An experimental high temperature electrochemical system was designed to measure electrochemical corrosion rates in dilute electrolyte solutions. The system was tested at temperatures up to 360°C and pressures up to 26 MPa. The ion concentrations in the aqueous boiler solutions are typically low, which makes corrosion rates relatively low and difficult to quantify using the traditional mass loss and metallography techniques. The electrochemical system designed with an annular-duct flow-through two-electrode assembly was proved to be efficient for in situ corrosion studies. The dc polarization and electrochemical impedance spectroscopy methods were found to be the most applicable techniques to measure the corrosion current in the high temperature/low density subcritical environments.