Measurement of hydrogen concentrations in B84360 grade SODcarbon-manganese steel using an electrochemical probe

In the work described in this paper, an improved electrochemical hydrogen probe was developed to allow rapid in situ measurements to be made on steel structures. The construction of the probe and the methods of surface preparation are discussed. The probe was used on welded BS4360 grade 50D carbon–manganese steel to determine· the way in which the hydrogen content of the parent plate, heat affected zones, and weld metal decreased with time. Other samples were subjected to typical service conditions by burying in different types of soil, exposing to sea water containing sulphate reducing bacteria, or applying cathodic protection. The resulting corrosion rates and hydrogen contents of the steel are compared.