Effect of a Stable Magnetic Field on Silicon Properties

The effect of a constant magnetic field (0.17 T) on microhardness, kinetics of photoconductivity decline and electro conductivity in silicon crystals is studied. The nature of changes of micromechanical and electrophysical characteristics in samples is investigated as a function of time elapsed after magnetic treatment. The results obtained are discussed in terms of magnetic field stimulated processes occurring in a subsystem of structural defects

Effect of a Stable Magnetic Field on Silicon Properties

The effect of a constant magnetic field (0.17 T) on microhardness, kinetics of photoconductivity decline and electro conductivity in silicon crystals is studied. The nature of changes of micromechanical and electrophysical characteristics in samples is investigated as a function of time elapsed after magnetic treatment. The results obtained are discussed in terms of magnetic field stimulated processes occurring in a subsystem of structural defects

Structural Phase Transition in CdSb + 3 % MnSb Composite at a High Hydrostatic Pressure

In CdSb + 3 % MnSb composite, structural properties have been studied, specific resistance ρ and Hall coefficient RH are measured at a high hydrostatic pressure of up to P ≤ 9 GPa. An irreversible structural phase transition is found at barometric dependencies p(P) and RH(P). From our experimental data, barometric dependencies of carrier concentration and their mobility are calculated. On the basis of the heterophase structure – effective medium model, characteristic points and parameters of the phase transition, and also dynamics of variation of the initial phase volume C1 as a function of pressure are computed. The latter dependence is in agreement with the investigation results of Raman scattering before and after application of pressure

Structural Phase Transition in CdSb + 3 % MnSb Composite at a High Hydrostatic Pressure

In CdSb + 3 % MnSb composite, structural properties have been studied, specific resistance ρ and Hall coefficient RH are measured at a high hydrostatic pressure of up to P ≤ 9 GPa. An irreversible structural phase transition is found at barometric dependencies p(P) and RH(P). From our experimental data, barometric dependencies of carrier concentration and their mobility are calculated. On the basis of the heterophase structure – effective medium model, characteristic points and parameters of the phase transition, and also dynamics of variation of the initial phase volume C1 as a function of pressure are computed. The latter dependence is in agreement with the investigation results of Raman scattering before and after application of pressure

Structure of Carbon Nanotubes in Colloidal Solutions under the Influence of a Constant Electric Field

Processes of self-organization in diffusive and limited conditions of colloidal solutions of carbon nanotubes under the influence of constant electric fields are studied. It is established that functionalized MCNT – COOH in a drop of colloidal solution is oriented in an electric field in a controllable way, which is of great practical value

Structure of Carbon Nanotubes in Colloidal Solutions under the Influence of a Constant Electric Field

Processes of self-organization in diffusive and limited conditions of colloidal solutions of carbon nanotubes under the influence of constant electric fields are studied. It is established that functionalized MCNT – COOH in a drop of colloidal solution is oriented in an electric field in a controllable way, which is of great practical value

Dimensional Effects in Micro- and Nanostructural Changes in Grain and Intragrained Structure of Steel 45 at Static-pulse Treatment

Conducted macro-, micro- and nanostructured materials were investigated by the influence of sample sizes of steel 45 in the form of a parallelepiped, after intense static pulse processing in plastic deformation as in the single (150 J), and pulsed (25 J) impact with a frequency of 23 Hz. When all modes of processing bulk samples found structuring self-organized formation of dislocations. With a single exposure revealed as filling pearlite grains periodic dislocations (200 nm), and the formation of dislocation-free regions. When a periodic pulse treatment of the samples with transverse dimensions fold speed of propagation of elastic waves and shock waves as well as the related transport velocity of dislocations turns shockwave mechanism causing the formation of alternating strips of ferritic and pearlite walls (25 microns), wherein the pearlite wall completely or partially filled with dislocations

The formation of the orthorhombic martensite in zirconium-base alloys

The structure of zirconium-base alloys with metals of V-VIII groups of the Periodic Table, quenched from high temperature $\beta$-phase region, was studied. X-ray diffraction analysis, light microscopy, and transmission electron microscopy were used in this investigation. It was found that the orthorhombic $\alpha''$-phase is formed only in the Zr-Ta, Zr-Mo. and Zr-Re systems within the composition ranges from 1.5 to 2.0 at.% Mo, from 5 to 11 at.% Ta, and in the $\rm Zr-1.5$ at.% Re alloy. The lattice parameters of the $\alpha''$-phase were found and it was established that the degree of rhombicity of the $\alpha''$-phase lattice increases with the increase of content of $\beta$-stabilizing element. The morphology and crystallographic features of the $\alpha''$-phase in these systems were studied. It is drawn the analogy between the orthorhombicity of the $\alpha''$-phase in zirconium-base and titanium-base alloys and the tetragonality of the $\alpha$-phase martensite in some iron-base alloys

Martensitic transformation and metastable ß-phase in binary titanium alloys with β\beta-metals of 4-6 periods

The structure of titanium-base alloys with d-metals of V-VIII groups of the Periodic Table, quenched from high temperature p-phase region, was studied. X-ray diffraction analysis, light microscopy, and transmission electron microscopy were used in mis investigation. It was established that the $\beta$-stabilising action of the alloying metal depends on its position in the Periodic Table. Both the group number and the period number influence on the minimum concentration of the alloying metal necessary for the complete stabilisation of the p-phase in quenched alloy. The dependencies of the lattice parameter of the p-phase from the alloying metal concentration for titanium alloys with d-metals of 4-th, 5-th, and 6-th periods were determined. The correlation between the M$_{\rm s}$ temperatures of binary titanium-base alloys and the position of alloying elements in the Periodic Table is established

Formation and Features of Adiabatic Shear Bands in Zr-Nb Alloys in Spherical Stress Waves

The adiabatic shear bands produced under loading by spherical stress waves in Zr—Nb alloys was studied by optical and transmission electron microscopy. The structure and distribution of the adiabatic shear bands were established depending on the loading conditions and the niobium content.Nous avons étudié par microscopie optique et électronique les bandes de cisaillement adiabatique produite sous la charge par les ondes sphérique tension dans les alliages Zr—Nb. Les effects de conditions charge et contenu du niobium sur la structure et la distribution de les bandes de cisaillement adiabatique sont présentés