Hydrogen-Induced Corrosion

Factor SCC Fatigue corrosion Hydrogen induced cracking... 

The protection potentials for seawater are described in Section 2.4. In pipelines and harbor installations, there is no limiting negative potential t/ for uncoated earbon steel or for steel provided with thiek eoatings over 1 mm, with yield points up to 800 N mm". With dynamieally highly loaded structures, the protection potential ranges in Table 16-2 should be adhered to as in the regulations [1-3] because of the risk of hydrogen-induced stress corrosion (see Section 2.3.4). 

Cracking mechanisms in which corrosion is implicated include stress corrosion cracking, corrosion fatigue, hydrogen-induced cracking and liquid metal embrittlement. Purely mechanical forms of cracking such as brittle failure are not considered here. 

Environmentally induced cracking consists of (i) stress corrosion cracking (ii) corrosion fatigue and (iii) hydrogen-induced cracking. The general features of these modes of failure are given below ... 

Currently, computer programs for corrosion assessment and control use a combination of expert systems and an object-oriented program such as evaluation of hydrogen-induced cracking of steels,35 or a combination of expert systems and neural networks in corrosion data modeling and prediction.32... 

W. Bruckhoff, O. Geier, K. Hofbauer, G. Schmitt, D. Steinmetz. Rupture of a Sour Gas Line Due to Stress Oriented Hydrogen Induced Cracking - Failure Analyses, Experimental Results and Corrosion Prevention. NACE Corrosion/85, Paper 389, Boston, USA, 1985-03-25/29. 

A. Punter, A. T. Fikkers, G. Vanstaen. Hydrogen-Induced Stress Corrosion Cracking on a Pipeline. Materials Performance 31(6), 24 (1992). (Proceedings of the Pipe Protection Conference, Cannes, France, 1991.)... 

Synthetic Slag (K2)-H20 H2 System. In order to extend the vapor transport conditions in slag systems to a reducing hydrous environment similar to that present in coal gasification, a series of TMS and KMS measurements were made using H2 or H2O as the initial reactant gas. With the TMS system, compositions of H2-N2-H2O up to 10 vol % H2 were attained prior to hydrogen-induced corrosive loss of the transpiration reactor. 

Nelson, H.G. and Williams, D.P., Quantitative observations of hydrogen-induced, slow crack growth in a low alloy steel, in Stress Corrosion Cracking and Hydrogen Embrittlement of Iron Base Alloys, Staehle, R.W., Hochmann, J., McCright, R.D., and Slater, J.E., Eds., NACE, Houston, TX, 1977, pp. 390-404. 

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