Влияние мощных потоков ионов дейтерия и дейтериевой плазмы на структурное состояние поверхностного слоя титана
The effect of a high-power pulsed flow of deuterium ions and deuterium plasma generated in a plasma focus setup on the surface structure of a Ti plate was investigated. It was established that, depending on the radiation-thermal conditions on the surface, three zones with different surface morphology, structure, and defects were formed in the surface layer irradiated. The peculiarities of the surface damage in the center of the irradiated region of the Ti target exposed to the most severe radiation (power density of the ion and plasma flows of qi ≈ 1011–1012 and qp ≈ 109–1010 W/cm2, respectively) were studied, as well as those for the peripheral region exposed to softer radiation.
The paper explored the possibility of obtaining coatings in the interior cavity of thin Cu tubes on the plasma focus devices. A special feature of such devices is the generation of thin plasma jets of high power. It has been shown the fundamental possibility of receiving protective coating in tubes (Cu) due to the erosion of the anode material (Cu, W). Coating was carried out under the influence of the impulse (t<0,1 µs) argon and deuterium plasma. Coating is a composite material with complex composition, containing the chemical elements, such as Cu, O2, C, W, Fe, Ni. It has been achieved a high value of strength for the coating obtained by processing of the inner cavity Cu tube by Ar plasma in a magnetic field B≤0,1 T.
The structural changes in the vanadium sample surface are studied as functions of the conditions of irradiation by pulsed high-temperature deuterium plasma and deuterium ion fluxes in the Plasma Focus installation. It is found that processes of partial evaporation, melting, and crystallization of the surface layer of vanadium samples take place in the plasma flux power density range q = 108–1010 W/cm2 and the ion flux density range q = 1010–1012 W/cm2. The surface relief is wavelike. There are microcracks, gas-filled bubbles (blisters), and traces of fracture on the surface. The blisters are failed in the solid state. The character of blister fracture is similar to that observed during usual ion irradiation in accelerators. The samples irradiated at relatively low power density (q = 107–108 W/cm2) demonstrate the ejection of microparticles (surface fragments) on the side facing plasma. This process is assumed to be due to the fact that the unloading wave formed in the sample–target volume reaches its irradiated surface. Under certain irradiation conditions (sample– anode distance, the number of plasma pulses), a block microstructure with block sizes of several tens of microns forms on the sample surfaces. This structure is likely to form via directional crack propagation upon cooling of a thin melted surface layer.
The method of Rutherford backscattering of He + ions 2 MeV studied profiles of C, Cu and W in the films deposited on the PF-4 LPI. The films were deposited on glass substrates in gases Ar, D2. It is found that the profiles of the elements is significantly dependent on the kinetic energy of the particles and their sizes. At particle velocities ~ 100 km / s, the particles penetrate to a depth of ~ 500 nm. Profiles are inhomogeneous in nature. For each impurity, there are certain depth beneath the surface layers of the glass. A special feature is the location of the films produced impurity layers below the surface of the glass substrate and overlapping. This arrangement sputtered layers is significantly different from the traditionally used methods of film deposition.
Samples in the form of assembly is pressed firmly against the two W-foil (230 microns), rolled and sintered powder were irradiated 10th pulses vysokotempera deuterium-temperature plasma (up to 10 keV) on the "plasma focus" (PF-4, FIAN) [ 1, 2] for the creation of shock waves and deuterium ion implantation. Options PF-4 and the exposure conditions N + - plasma and posleradiatsionnyh investi--ments are described in [1, 2]. It performs measurements of the neutron yield from W foils. Made SEM analysis of the structure and elemental composition of the surface of the irradiated foils W. Conducted RBS and ERD study of foil on both sides showed that deuterium ions under the influence of shock waves knocked out of the first W-foil and penetrate into the second W-foil, as initially present in the sample hydrogen redistributed. The measured depth profiles of all distributions and integral concentration of deuterium and hydrogen, both sides of each of the foils are presented. The model describes the observed effects of the first knockout deuterium implanted deuterium W foil and redistribution of hydrogen is discussed.
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
Radiation conditions are described for various space regions, radiation-induced effects in spacecraft materials and equipment components are considered and information on theoretical, computational, and experimental methods for studying radiation effects are presented. The peculiarities of radiation effects on nanostructures and some problems related to modeling and radiation testing of such structures are considered.
This volume presents new results in the study and optimization of information transmission models in telecommunication networks using different approaches, mainly based on theiries of queueing systems and queueing networks .
The paper provides a number of proposed draft operational guidelines for technology measurement and includes a number of tentative technology definitions to be used for statistical purposes, principles for identification and classification of potentially growing technology areas, suggestions on the survey strategies and indicators. These are the key components of an internationally harmonized framework for collecting and interpreting technology data that would need to be further developed through a broader consultation process. A summary of definitions of technology already available in OECD manuals and the stocktaking results are provided in the Annex section.