No abstract available

[en] The strength and ductility of polycrystalline scandium have been studied as a function of hydrogen concentration and test temperature. The effects of hydrogen on the mechanical behavior of scandium are discussed in terms of current embrittlement concepts for hydride forming metals. Hydrogen concentrations ranging from 0.20 to 20.83 atomic percent and temperatures from 78 to 473K were employed in this investigation. SEM fractographs are shown to illustrate the modes of tensile failure

[en] The interaction of a proton with an aluminum host is treated within the spherical model of a solid. Our results give for the heat of solution and activation energy of H in Al 0.593 and 0.5 eV, respectively, compared with the experimental values of 0.66 and 0.52 eV. The previously untreated nonspherical corrections are also estimated and shown to be small

[en] Structural studies of polycrystalline H_0.57 ReO₃ grown with age of ReO₃ placed in air for 2 1/2 years, at normal room temperature conditions, are reported. 13 refs, 1 tab

[en] The effects of hydrogen and other environments on the fracture strength of soda-lime glass and silicon have been investigated using ultrahigh vacuum techniques for precise environmental control. Samples were scribed, soaked, and fractured in vacuum, water vapor, and hydrogen environments. Four-point flexure strength measurements, exoelectron emission, constant moment double cantilever beam slow crack propagation, and previous acoustic emission drilling/grinding experiments all show that hydrogen affects crack propagation. In controlled environments, increases in strength of as much as 235% of the vacuum strength were observed for vacuum scribed-hydrogen soaked soda-lime glass. The separate and synergistic effects of residual stress, hydrogen, water vapor, and air environments are discussed in terms of a hypothesis involving chemical reactions at the surface, residual stress relief in active environments, and stresses arising from diffusional concentration gradients

No abstract available

[en] In the present communication, chemical states of the hydrogen-ion bombarded yttrium are investigated by means of X-ray photoelectron spectroscopy (XPS), and the results are compared with the spectra of thermally synthesized hydride. The dehydrogenation behavior of the implanted sample is also examined in the temperature range up to 400⁰C. (orig./RK)

[en] The effect of metal-metal contact on charged particles has been considered. It was shown that when hydrogen exists in metal in the form of positive ions, i.e. protons, one should expect a directional action of the contact on hydrogen transport. The possible applications of such effects are pointed out, one of which is the possibility of the prevention of hydrogen escape from reactor materials. (author)

No abstract available

[en] The exposure of the miscut Si(001) surface to H gives rise to a rich sequence of stable step structures as a function of the H chemical potential. First-principles calculations of step-formation energies show that the formation of steps on the (2x1) reconstructed surface requires energy, but that on the (1x1) surface, steps form exothermically. This explains surface roughness at high H chemical potentials