On physical properties of nanoparticles: size effect and scale of nanoobjects

A transition border between macroscopic and nanoscale states of solids associated with change of its physical properties is certain to exist. The change of mechanical, magnetic, thermal and other properties of nanoparticles may be due to the surface tension, decrease in coordination number in the topsurface layer, rebuilding of the electron shell structure, change of the symmetry group of the crystal lattice and the binding energy

Tribology properties changes of nanocrystalline Al–Si–N films after annealing

Методом АСМ исследованы микроструктура поверхности, шероховатость и коэффициент трения нанокристаллических пленок l–Si–N % в исходном состоянии и после воздействия отжига в вакууме при температурах 600, 800 и 900 °С.The surface microstructure, roughness and coefficient of friction of nanocrystalline Al–Si–N films in the initial state and after annealing in vacuum at of 600, 800 and 900 °C were investigated using AFM.Работа выполнена при поддержке ГПНИ «Энергетические системы, процессы и технологии» подпрограммы «Эффективные теплофизические процессы и технологии»

Thermal Stability of the Structure and Phase Composition of Titanium Treated with Compression Plasma Flows

The results of studying the structure and phase composition of the surface layer of commercial pure VT1-0 titanium treated with compression plasma flows in nitrogen atmosphere and annealed in the temperature range of 400–900°C for 1 h are presented. Using the X-ray diffraction method, the α-Ti(O) solid solution is found to form in the titanium surface layer at 500°C, without pretreatment with plasma, and to transform into the titanium oxide TiO2 (rutile) phase at 600°C. Pretreatment of titanium with compression plasma flows promotes the formation of α-Ti(N) solid solution decreasing the rate of surface oxidation and increasing the initial temperature of rutile formation to 700°C, which indicates enhancement of the thermal stability of this structure

Nitriding of commercial pure titanium in the plasma of frequency-pulsed non-selfsustained glow discharge with a hollow cathode at low pressure

glow discharge with a hollow cathode at the temperatures 600–700°C for 3 h was carried out. By means of X-ray diffraction and transmission electron microscopy the change in the phase composition of titanium after nitriding has been revealed. Increase in the nitriding temperature from 600 to 700°C results in the rising of the volume fraction of nitride phase TiN, Ti2N, and TiN0.3. The results showed the threefold increase in the microhardness and the twentyfold increase in the wear resistance as compared to untreated titanium