There is considerable evidence indicating that hydrogen entry into the metal may be a fundamental part of the stress corrosion cracking (SCC) of stainless steels in hot chloride containing water.1 Hydrogen entry appears also to be a crucial factor in certain instances of pitting-embrittlement attack in mild steel power generating boilers.2,3 Relatively little study has been made in the laboratory, however, of hydrogen entry and permeation in metals corroding in high temperature water, possibly because of the experimental difficulties involved. This communication describes a simple electrochemical cell, using a stressed tube working electrode, which allows hydrogen permeation measurements to be made in SCC experiments at temperatures up to 300 C (572 F).
The cell (Figure 1) uses a section of pipe, 5 1/2 inches long, 5/8 inch OD, and 0.065 inch wall thickness, as both cell wall and counter electrode. It is normally of the same...
