Estimation of partial contributions of the protective phase film and the inhibitor into a retardation of metal corrosion

Issue 1(55) 2010
Pages 55-62
Vigdorovich V.I., Tsygankova L.E., Fedotova A.I.
Keywords: carbon steel, hydrogen-sulfide media, corrosion, protection, phase films

The method of an estimation is offered for the contributions of the protective phase film and the inhibitor into a retardation of metal corrosion in the solutions where such surface coatings are formed (in particular, hydrogen sulfide and carbonic acid corrosion of carbon steel). The principles of a calculation of Z film and Z inh are suggested in such conditions. As an example, the experimental data are given for the dependence of total corrosion rate of St3 steel in the hydrogen sulfide media (50...200 mg/l H 2S). In such conditions the contributions of the phase polysulfide film and EM-12 and EM-13 inhibitors into the corrosion retardation are given.