Hydrogen generation and permeation through steel in contact with non-aqueous media

Abstract

Hydrogen embrittlement has been an important issue in industrial applications and is particularly severe in steels because of the high mobility of H in Fe. Critical hydrogen contents lead to embrittlement and therefore to shorter durability of the compartment. The Devanathan-Stachurski cell is an established method for hydrogen permeation measurements through metal membranes in contact with aqueous media. The oxidation current of permeated hydrogen that diffused through a metal membrane is measured and from that the amount of permeated hydrogen could be calculated (Faraday’s law). The main goal of this work was to characterize technologically relevant lubricant media (oils) in terms of hydrogen generation and permeation through a steel membrane in contact with oil under the influence of temperature and electrostatic voltage. For this, one has dealt with sample preparation, cutting the 100Cr6 steel samples into discs, grinding and PVD coat them with a Pd layer. For the experiments a modified DS cell2 was used, due to the high resistance of the oil. Further modifications to the set up and experiments for investigating the effect of electrode distance/oil volume, temperature, different working-electrodes (mild steel, Pd, 100Cr6 steel) polarization strength and time duration were carried out.Using Pd foil or 100Cr6 steel as working electrode a polarization-related effect on the hydrogen permeation current was visible at higher polarization voltage (70 V) and smaller distance between the electrodes in the input cell.Further investigations and optimization are necessary to enable application of the set up in industrial environment.