AC technique to monitor localized corrosion in PWR steam generators. Final report

Laboratory tests have shown that the a.c. electrochemical technique being developed meets the basic requirements for in situ corrosion monitoring of the secondary side of PWR steam generators. The technique uses two probe electrodes which measure the electrochemical impedance of the corroding surface. The electrochemical impedance varies with the kinetics of corrosion, and can be used to indicate the onset of rapid corrosion. This has been demonstrated experimentally. Low temperature experiments simulating model operating conditions, have shown that the technique can determine the impedance of a local crevice region under conditions of high resistivity water and local boiling agitation