Hydrogen embrittlement and

Gibala R and Hehemann R F (eds) 1984 Hydrogen Embrittlement and Stress Corrosion Craoking (Metals Park, OH American Soceity of Metals)... 

For many years hydrogen was considered as a deleterious impurity which deteriorates mechanical properties of materials. This is clearly illustrated by hydrogen embrittlement of ferrous metals and alloys. The main effort of the research was aimed therefore at the study of hydrogen embrittlement and at the ways to avoid it. ... 

Despite considerable developments in the study of stress-corrosion cracking mechanisms in recent years, it remains difficult to draw a clear distinction between those situations which involve hydrogen embrittlement, and those... 

Despite the major technical importance of hydrogen embrittlement, and the wealth of research work on the subject, the mechanism (or perhaps mechanisms) of hydrogen embrittlement remains uncertain. Much of the book edited by Oriani, Hirth and Smialowski is concerned with mechanistic aspects of hydrogen embrittlement, and the reader is referred in particular to the summary by Thomson and Lin . 

Duquette, D. J., Fundamentals of corrosion fatigue behaviour of metals and alloys , in Proc. Conf. Hydrogen Embrittlement and Stress Corrosion Cracking, Cleveland, Ohio, 1-3 June 1980, Case Western Reserve University Department of Metallurgy and Materials Science, pp. 249-70 (1980)... 

Safety issues, low or inexistent NOx emissions, injectors requirements, adequate compression ratios, system design and appropriate use of materials to avoid problems such as hydrogen embrittlement and chemical attacks are part of the technological solutions incorporated in the Alset fully engineered System. 

E. SNAPE obtained his BS and PhD degrees in Metallurgical Engineering from the University of Leeds in 1965. During his research career with Inco, he received numerous awards for his work on stress corrosion and hydrogen embrittlement, and became an international authority on this subject. In 1974, Dr. Snape pioneered the development of a waste reclamation process which now is being applied to the recovery... 

The heart of corrosion science has been identified as electrochemical science coupled with the thermodynamic and kinetic values. Other limbs are oxidation and high-temperature oxidation of metals, protective coatings, passivity, inhibitors, microbial-induced corrosion, corrosion fatigue, hydrogen embrittlement and corrosion-resistant alloys. Having identified the limbs of corrosion science, it is instructive to examine how the various aspects came into existence over a period of time. 

A.R. Troiano Hydrogen Embrittlement and Stress Corrosion Cracking 1984... 

Szklarska-Smialowska, Z., Hydrogen Embrittlement and Stress Corrosion Cracking, R. Gibala, R.E Hehemann (eds.), ASM International, pp. 99 207-230, 1995. 

Limited data show that both welding practice and location of defects can dictate the hydrogen embrittlement snsceptibility of a weld. A study on microalloyed steel API 5L Grade X60 examined weld joints that were fabricated using either one or two weld passes." Fractnre mechanics specimens were extracted from the base metal, fusion zone, and heat-affected zone and tested in 7-MPa hydrogen gas. Results showed that Kj values measured in the weld fnsion zones were similar to valnes in the base metal, i.e., Rju was approximately 100 MPaVm in each region. In contrast, the heat-affected zones were more susceptible to hydrogen embrittlement, and Rju was difficult to measure. The heat-affected zone in the two-pass weld was most susceptible. 

A/cm. The choice is between higher protection at the risk of local overprotection (and possible hydrogen embrittlement) and less protection at the risk of corrosion, particularly in regions farther from the anodes. It is also a choice between the high cost of electric power on the one hand and the need for more frequent maintenance due to incomplete protection from corrosion, on the other. 

---