Effects of hydrogen on metals

Stewart, A. T., Effect of hydrogen on fatigue crack propagation in steels , Proc. Int. Conf. on Mechanisms of Environment Sensitive Cracking in Materials, University of Surrey, 4-7 April 1977, The Metals Society, pp. 400-11 (1977)... 

Without metallic components, the promotion effect of hydrogen on the... 

E. B. Norris and E. A. Sticha, Effect of Hydrogen on the Stress-Rupture Strength of 2- 4Cr-lMo Steel, Metal Properties for the Petroleum and Chemical Industries (ASME G00103/MPC-2), American Society of Mechanical Engineers, New York, 1976, pp. 590-592. 

Hydrogen, however, may also react with other impurities such as dissolved oxygen, sulphur, carbon, etc. and form high activity products. Therefore, the effect of hydrogen on the mechanical properties of a crystal is ambiguous. A discussion of fracture at metal/oxide boundaries has been given recently by [F. Ernst (1995)]. 

Acids are a part of our environment, present in food and in rain, and a component of skin moisture. It is necessary to consider the effect of acids on metals used to make jewelry. In Chapter 3 we learned that acids produce hydrogen ions (H+) in aqueous solutions. Metal atoms tend to be effective reducing agents, losing electrons to become more stable. Some metals are better reducing agents than others. For example, zinc atoms lose electrons more easily than iron atoms, which, in turn, lose electrons more easily than copper atoms. 

After reaction with the monomer to form a new propagating chain the position is formally the same as transfer with monomer. However, the two mechanisms can be distinguished kinetically if realkylation of the catalyst is slow compared with propagation. There is no direct evidence for this reaction although it is well established that the relatively stable alkyls of ms nesium and aluminium form metal hydride bonds on decomposition at elevated temperatures [83]. The existence of spontaneous termination has been deduced from a consideration of the kinetics, and by analogy with the effects of hydrogen on the polymerization. 

IM Bernstein and AW Thompson, Hydrogen in metals , in Proceedings of the International Conference on the Effects of Hydrogen on Materials Properties and Selection and Structural Design (Champion, PA, 1973) American Society for Metals, Metals Park, OH, 1974. 

The design and construction of small-scale pilot-plant units for processing under extreme conditions of pressure and temperature have been described. This description includes material on constructing barricades, thick-walled pressure vessels, and pumps as well as information on the selection of alloys and the effects of hydrogen on the properties of metals. 

Recently, there have been many reports on the effects of CD on metal catalytic systems. A potentially interesting approach for the modification of catalytic systems based on metal complexes, such as Zn, Mo, Fe, In, Sn, Pd or Ru, involves the use of CD as a protective agent. There are many reports on the interaction between CDs and metallic nanoparticles.Immobilized CD on Pd nanoparticles was employed as an efficient mediator in aqueous biphasic hydrogenation reactions (Figure 4.6a,b). ... 

The authors of [39] determined the functions semiempirically that enter in (11.15) and applied them to the following problem surface energy in nickel and palladium, binding of the hydrogen atoms to vacancies in these metals, stracture of surface layers, and effect of hydrogen on fracture. 

Sofronis P, Robertson IM. TEM observations and micromechanical/continuum models for the effect of hydrogen on the mechanical behavior of metals. Philos. Mag. A 2002 82 3405-3413. 

Tabata T, Birnbaum HK. Direct observations of the effect of hydrogen on the behavior of dislocations in iron. Scr. Metall. 1983 17 947-950. 

Mclnteer WA, Thompson AW, Bernstein IM. The effect of hydrogen on the slip character of nickel. Acta MetalL 1980 28 887-894. 

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