Hydrogen permeation studied by electrochemical techniques

In this paper impedance measurements, weight loss and hydrogen permeation t ests were used to characterise the H2S corrosion process. In a classical pe rmeation cell, where a steel membrane is separating two electrolytic soluti ons, it was seen that the detection of hydrogen diffusing through the steel is totally controlled by the anodic reactions occurring at the steel/H2S i nterface. Solutions with different aggressiveness were used to define the m aximum acceptable permeation current to avoid cracks nucleation and propaga tion. From these tests a procedure was developed to monitor hydrogen induce d cracking (HIC) in industrial plants. (C) 1999 Elsevier Science Ltd. All r ights reserved.