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The effect of irradiation with a pulsed electron beam on the diffusion of titanium in the polycrystalline Zr-1 wt.% Nb alloy is studied using high-frequency glow discharge optical emission spectrometry. The depth distribution profiles of titanium concentration in the Zr-1 wt.% Nb alloy after isothermal diffusion annealing and annealing under surface irradiation with a pulsed electron beam are determined. It is shown that under simultaneous exposure to temperature and irradiation with a pulsed electron beam, an increase in the coefficient and a decrease in the activation energy of grain boundary diffusion are observed in the near-surface layer of the alloy. [ABSTRACT FROM AUTHOR]

The effect of pulsed electron beam (PEB) irradiation modes on the structure formation and properties of the near-surface layer of titanium alloys of the Ti–6Al–4V–H system has been studied. The microhardness, elasticity modulus, friction coefficient, and plasticity (Hμ/E) and resistance ( H μ 3 / E2) indices have been determined. PEB irradiation in the mode without surface melting is shown to reduce the strength characteristics and the Hμ/E and H μ 3 / E2 indices of the near-surface layer of alloys. Because of PEB irradiation in the surface melting mode, a two-phase α + α'' lamellar structure with increased Hμ/E and H μ 3 / E2 indices is formed in the near-surface layer of alloys ~10 μm thick. The effect of the near-surface layer properties on the alloy resistance to deformation under tension and creep has been studied. [ABSTRACT FROM AUTHOR]

The effect of irradiation of ultrafine-grained (UFG) nickel with a pulsed electron beam (PEB) in the mode without surface melting on the copper diffusion in the near-surface layer is studied. The profiles of copper concentration distribution over the depth after isothermal diffusion annealing and PEB-irradiation annealing of the UFG nickel surface are determined. It is found out that as a result of PEB irradiation, the coefficient of grain-boundary diffusion of copper in nickel increases and the mode of grain-boundary heterodiffusion in the near-surface layer of nickel changes in comparison with isothermal diffusion annealing. [ABSTRACT FROM AUTHOR]

Comparative studies of the effect of pulsed electron beam irradiation of the Ti–6Al–4V titanium alloys with the contents of hydrogen of 0.002 wt.% (VT6 alloy) and 0.23 wt.% (VT6–0.23H alloy) on their structure and peculiar creep behavior are performed at a temperature of 723 K within the range of creep rates 10–7–10–5 s–1. It is found out that irradiation of the VT6 and VT6–0.23H alloy samples with electron beams in the no-melting mode neither changes nor increases their steady-state creep. It is shown that formation of a modified surface layer during electron beam irradiation in the melting mode gives rise to a decrease in the steady-state creep rate in the VT6 alloy and its increase in the VT6–0.23H alloy. It is demonstrated that the dependence of the steady-state creep of the VT6 alloy on the stress before and after pulsed electron beam irradiation is satisfactorily described by the creep power law. The presence of hydrogen in a solid solution in the VT6–0.23H alloy violates the creep power law. The physical causes for the high values of a stress sensitivity index and an effective creep activation energy of the VT6 and VT6–0.23H alloys are discussed. [ABSTRACT FROM AUTHOR]

Using the methods of electron backscatter diffraction, electron microscopy and X-ray diffraction analysis, it is demonstrated that irradiation of the surface of a submicrocrystalline molybdenum specimen with a pulsed electron beam in a non-melt regime results in the formation of a gradient structure in its bulk. The irradiation temperature is shown to affect the density of defects, the value of stress, and the distributions of grain-boundary misorientations in the surface and bulk of the submicrocrystalline molybdenum specimens. [ABSTRACT FROM AUTHOR]

A pulsed action of an electron beam on a Zr-1% Nb zirconium alloy is studied. Alloy samples are irradiated by three 50-μs pulses at an energy density of 15-25 J/cm, a power of (3-6) × 10 W/cm, a current density of 10-50 A/cm, and an electron energy of 18 keV. This method of processing is found to modify the surface layer of the alloy without changing the structure-phase state of its volume. This surface modification increases the hydrogen saturation resistance of the alloy. [ABSTRACT FROM AUTHOR]