Extensive studies1-3 have been carried out by Economy, Wootten, et al., to understand the phenomenon of denting which occurs in Inconel 600 heat exchanger tubing in nuclear steam generators at places where they pass through carbon steel support plates. We report herein some laboratory observations of the crevice region that indicate the importance of galvanic effects within the crevice region.
The technique for developing the crevice was similar to that used by Vaia, et al.1 in which a carbon steel plug was supported on an Inconel 600 sheet formed in the shape of a cone within an Inconel 600 tube. A diagram of the system and the important dimensions are shown in Figure 1. The crevice between the carbon steel plug and the Inconel tubing was circular in shape and had an average width of 0.010 in. The Inconel tubing was washed with detergent, rinsed with...
