In this article the matters of the structure of TiN coatings in the function of the parameters of ion-plasma vacuum treatment are addressed and their temporal evolution is considered.
The effect of the reference voltage on the texture in TiN, ZrN, Nb, Ta and W coatings obtained by PVD methods was investigated by X-ray method. It is shown that an increase in the reference voltage ...leads to an increase in the {111} texture to a weakening of this texture in W coatings. The results were interpreted on the basis of the features of elastic anisotropy in the material of coatings with a cubic lattice.
The possibilities of using active neutral particle diagnostics for measuring local ion temperatures and isotopic ratio of deuterium-tritium plasma at the tokamak with reactor technologies are ...considered. Options for positioning the neutral particle analyzer relative to the diagnostic injector are presented. The fluxes of deuterium and tritium atoms escaping out of plasma were simulated in a wide range of plasma densities and temperatures. It is shown that the neutral particle analyzer active diagnostics will make it possible to measure the plasma parameters mentioned with the spatial and time resolutions of ~14 cm and ~0.01–0.1 s, respectively.
The control of the deuterium–tritium (DT) fuel isotopic ratio has to ensure the best performance of the ITER thermonuclear fusion reactor. The diagnostic system described in this paper allows the ...measurement of this ratio analyzing the hydrogen isotope fluxes (performing neutral particle analysis (NPA)). The development and supply of the NPA diagnostics for ITER was delegated to the Russian Federation. The diagnostics is being developed at the Ioffe Institute. The system consists of two analyzers, viz., LENPA (Low Energy Neutral Particle Analyzer) with 10–200 keV energy range and HENPA (High Energy Neutral Particle Analyzer) with 0.1–4.0MeV energy range. Simultaneous operation of both analyzers in different energy ranges enables researchers to measure the DT fuel ratio both in the central burning plasma (thermonuclear burn zone) and at the edge as well. When developing the diagnostic complex, it was necessary to account for the impact of several factors: high levels of neutron and gamma radiation, the direct vacuum connection to the ITER vessel, implying high tritium containment, strict requirements on reliability of all units and mechanisms, and the limited space available for accommodation of the diagnostic hardware at the ITER tokamak. The paper describes the design of the diagnostic complex and the engineering solutions that make it possible to conduct measurements under tokamak reactor conditions. The proposed engineering solutions provide a safe—with respect to thermal and mechanical loads—common vacuum channel for hydrogen isotope atoms to pass to the analyzers; ensure efficient shielding of the analyzers from the ITER stray magnetic field (up to 1 kG); provide the remote control of the NPA diagnostic complex, in particular, connection/disconnection of the NPA vacuum beamline from the ITER vessel; meet the ITER radiation safety requirements; and ensure measurements of the fuel isotopic ratio under high levels of neutron and gamma radiation.
An X-ray diffraction method was used to study the formation of the crystallographic texture of vacuum ion-plasma TiN and ZrN coatings depend on the bias voltage on the substrate. It is shown that, at ...high values of the bias voltage (-100 V), a pronounced texture forms in TiN coatings and a two-component (111) + (113) texture in ZrN coatings. A decrease of the bias voltage to -10 V leads to a twofold increase in the hardness of the coatings, a non-texture state of TiN, and a weakening of the texture of ZrN coatings.
The applicability of neutral particle diagnostics for studying plasma parameters and additional methods of heating in the Tokamak with Reactor Technologies is analyzed. Options for the arrangement of ...diagnostic equipment, which includes three analyzers of charge-exchange atoms (neutral particle analyzers) for different energy ranges of recorded atomic fluxes, are given. It is shown that the diagnostic complex of analyzers makes it possible to measure the distribution functions of plasma thermal ions and to obtain information on the isotopic ratio of the main plasma ion component in the deuterium–tritium mode of facility operation. In addition, the proposed geometry of the analyzer arrangement makes it possible to measure the energy distribution of fast ions, which arise during neutral beam injection and ion cyclotron heating of plasma.
The phase composition, texture and anisotropy of the mechanical properties of 2 mm sheets of Mg-9Li-3Al-0.4Ce alloy were studied by X-ray diffraction and mechanical tests. It is shown that the alloy ...contains two solid solutions, the α phase with HCP lattice based on Mg and the β phase with BCC lattice based on Li. Intermetallic Al12Mg17 is also present in the alloy. Alloy sheets are characterized by a basal α-phase texture. At the same time, the most durable prismatic orientations are mainly located in the transverse rolling direction (TD), which leads to higher strength properties in this direction compared to the rolling direction (RD). The texture of the basicβ-phase in RD and TD does not differ and, accordingly, does not contribute to the anisotropy of strength properties.
A scheme of a multichannel time-of-flight atomic analyzer with an electrostatic deflection system that provides two-dimensional focusing of the ion beam in the transverse direction is described. A ...thin carbon film with a thickness of 100 Å is used to ionize the incoming flow of atoms. The results of numerical simulation of the main parameters of the analyzer, such as the energy values in the channels, their energy resolution, and permeability, are given. An example of the possible use of such an atomic analyzer for measuring the energy distribution function of thermal plasma ions and fast ions of heating beams in the deuterium–tritium operating regime of the TRT facility is considered. The efficiency of radiation background suppression in the analyzer detection system by the coincidence circuit has been analyzed.
The plasmaphysical code is presented that makes it possible to simulate the energy distributions of atoms escaping from plasma of the toroidal facilities. The code includes calculations of the ...particle spatial distributions in the charge-exchange plasma target consisting of atoms and hydrogen-like impurity ions. The calculations of the charge-exchange target are performed in two ways: using the Monte Carlo method and solving the ionization balance equation in the coronal approximation. The code can be used to interpret the neutral particle analyzers (NPAs) data. In particular, with its help, the ion temperatures determined using the NPAs can be corrected. The code can be also used to estimate the atomic fluxes from plasma onto the first wall expected at the currently designed fusion facilities.
Academician A. D. Sakharov’s idea concerning the emission of atomic flux from hot plasma (1951) inspired scientists of A. F. Ioffe Physico-Technical Institute to create the first in the world ...instrument called Neutral Atom Analyzer in 1960 and then in 1961 to use it successfully on the Alpha device (USSR, 1958–1963). Now the analysis of fluxes of fast atoms referred to as Neutral Particle Analysis (NPA) is one of the main diagnostic methods for the ion component of plasma in tokamaks, stellarators, and other devices. NPA provides a unique opportunity for studying the ion distribution functions, ion temperatures and hydrogen isotope ratio in hot plasma. Neutral particle analyzers developed at the Ioffe Institute were widely used in the USSR until the late 1970s, and afterwards began to be employed worldwide. Since then, most of the information on the ion distribution functions and the behavior of fast ions in fusion plasma is obtained from NPA measurements on all leading magnetic confinement fusion systems worldwide. The specialized complex of atom analyzers currently being created at the Ioffe Institute is included in the primary list of ITER diagnostics. The integration of this complex on ITER is expected to begin in 2025.
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