7. Hydrogen-metal interaction

In the course of its metallurgical history and during its use, a metallic material such as steel is subjected to various sources of hydrogen.

Hydrogen-steel interaction can cause significant material deterioration due to loss of mechanical properties, leading to delayed part failure. The importance of this phenomenon and its consequences justifies the multitude of studies dedicated to it.

In an electro-galvanizing range, chemical and/or electrolytic treatments generate hydrogen. While the volume of hydrogen produced can be reduced, it cannot be totally avoided, either during the deposition phase or during prior chemical and/or electrolytic treatments, known as "preparation" treatments, such as cathodic degreasing or acid pickling of the steel. A closer look at the preparation sequence shows that, when anodic alkaline degreasing is carried...