A prediction method for the general corrosion behavior of Alloy 690 steam generator tube using eddy current testing

• A corrosion test for the tubes with different levels of eddy current noise was conducted.
• A relationship between the corrosion rate and the eddy current noise of tubes was explored.
• Corrosion rate was closely correlated to the tube noise of a rotating pancake probe.
• Corrosion rate was not related to the tube noise measured using a bobbin probe.

The purpose of this work is to develop an eddy current testing method to predict the general corrosion behavior of Alloy 690 steam generator tubes. A corrosion test was conducted for tubes with different levels of eddy current noise in simulated primary water at 330 °C, and their corrosion behavior was correlated with the tube noise measured using bobbin and rotating probes. The corrosion behavior was closely correlated with the tube noise measured using a rotating probe. However, there was no correlation between the corrosion behavior and the tube noise measured using a bobbin probe. The tube noise value measured using a rotating pancake coil probe is suggested to be a significant parameter in estimating the general corrosion behavior of tubes.