Optimizing the mechanical properties of steel and alloys by adjustment of the defect nanostructure

The influence of the residence time of 30XΓCA and P18 steel and also VT20 titanium alloy in conditions of polymorphous austenitic and bainitic pretransformation and transformation on their mechanical properties is investigated. The results show that phase transformations permit regulation of alloy structure and properties over a broad range (from properties typical of the quenched state to those of tempered metal). By working at the boundary of polymorphous transformation, the density of the defect structure may be equalized, and the mechanical properties of the alloys may be optimized. Acoustic emission may be used to determine the stage of phase transformation. On that basis, heat treatment that permits the most effective use of the phase transformation is developed.     

Models of Ceramic Tritium Breeding Zones in the Blanket of a Thermonuclear Reactor

The development, performed in the 1980s–1990s, of models of tritium breeding zones for blankets of thermonuclear reactors, based on the use of ceramic lithium-containing materials, is described. 5 figures, 1 table.     

Prospects for Consteel technology in Russia

The development of the Consteel process is briefly analyzed. Foreign experience with the Consteel system and its derivatives (Faststeel and Consteel Evolution) is discussed. Its introduction in Russia is expedient for the production of high-quality steel.     

Operation mode of the proton injector in the linac of the Institute for Nuclear Research with a 100-Hz pulse repetition rate

Results of the analysis and upgrading of the high-voltage pulse generator circuit in the proton injector for operation with a 100-Hz pulse repetition rate are presented.     

The thermal effect on magnetic properties of iron-containing coatings formed on titanium by plasma-electrolytic oxidation

The effect of annealing in air at T _an temperature up to 800°C on the magnetic characteristics, elemental and phase composition, and surface morphology of iron-containing oxide coatings on titanium is studied. Annealing at T _an ?? 500°C does not seem to affect the composition and morphology of coatings. The coercive force (H _c ) of specimens equals 70 Oe at room temperature and 256 Oe at 2 K. Upon annealing at 700 or 800°C, the H _c value decreases to 13 Oe. The change in the magnetic characteristics correlates with the crystallization of a number of iron and titanium phosphates, the redistribution of elements in the coatings and pores, and the surface formation of microcrystals and whiskers.     

Gravitation theory with a Dirac scalar field in the exterior form formalism and the cosmological constant problem

As a consequence of the Poincare-Weyl gauge theory of gravity, the space-time possesses the geometric structure of Cartan-Weyl CW ₄ space with curvature and torsion 2-forms and a Weyltype nonmetricity 1-form. The Dirac field ??(x) appears as an essential additional geometric component with respect to the metric tensor. The conformal theory of gravity coupled with ??(x) in the exterior form formalism is considered. At an early stage of the universe evolution, we consider these field equations for the spatially flat FRWmetric, assuming the densities of ordinarymatter and dark matter to be very small. Then the field equations can be expressed in terms of the metric tensor and ??(t) only and have an exponentially diminishing solution for ??(t), which can explain an exponential decrease of dark energy (the energy of physical vacuum) as a function of time as a consequence of field dynamics in the ultra-early Universe.     

Effect of external signal on the output power of an oscillator with electron feedback

The effect of an external single-frequency harmonic signal on the output power of an oscillator with electron feedback has been studied by analytical and numerical methods. It is established that an increase in the input signal power leads to sharp growth in the output power of the nonautonomous oscillator. Physical processes that take place in the electron beam with virtual cathode under the action of an external harmonic signal, which leads to velocity modulation in the electron beam entering the interaction space, have been analyzed. The obtained results well agree with the data of previous experimental investigations of the signal gain in a low-voltage vircator.