A. V. Shuklinov

Micro- and nano-indentation approach to strength and deformation characteristics of minerals

In focus are methodology and effect of micro- and nano-indentation method in studying local deformation and failure of rocks. By micro- and nano-indentation, numerical values of Young’s modulus, and hardness of rocks and minerals have been obtained. The values of fracture toughness are obtained for separate minerals and at grain boundary. The authors highlight the use perspectiveness of the described method in estimating strength and deformation characteristics of rocks.

Electrodeposition of nickel nanoparticles onto multiwalled carbon nanotubes

The process of nickel nanoparticle nucleation and growth during galvanochemical deposition on the surface of multiwalled carbon nanotubes has been studied. The dependences of the morphology, size, and spacing of nickel nanoparticles on the deposition time at a current density of 5 and 0.5 A/dm2 are determined.

Size effects in the hardness of fcc metals on micro- and nanoscales

The size effects in the hardness of three fcc metals, namely, Ni, Cu, and Al, are studied by micro- and nanoindentation, and the boundaries of regions with size effects of various types and the characters of these effects are determined.

The Size Effects in Hardness of Polycrystalline Niobium

The indentation size effect on the hardness of polycrystalline niobium has been studied. A relationship between the material hardness and the indenter mark dimensions is established in a broad range of indentation depths (20 nm–70 μm).

Modification of aluminum antifriction alloys by carbon nanomaterials

A procedure is developed for modification of the near-surface layers of AO-20-1 alloy (AlSn20Cu, GOST Standard 14113–78) by carbon nanotubes at a depth of 2 μm. Data on the depth distribution of carbon across the near-surface layer are obtained. Mechanical and tribological tests of the modified layer are performed. It has been found that the hardness of the near-surface layer increases by 10–60% at a depth up to 1 μm and the friction coefficient decreases by ∼25 %.

The influence of low-intensity beta radiation on crack susceptibility under indentation of silicon

The dependence of the lengths of radial cracks formed during indentation of silicon single crystals on the depth of imprint has been studied using electron microscopy. The influence of low-intensity (I = 105 cm−2 s–1) beta radiation on the crack susceptibility during indenter penetration to a depth of ∼2.5 μm has been revealed.

Beta-induced reduction in Cu/Si-structure adhesion

The effect of low-flux (I ∼ 1.8 × 105 cm−2 s−1) β irradiation on the process of the delamination of thin copper films (with a thickness of ∼100 nm) from a silicon substrate under indentation by a Berkovich pyramid is studied. It is revealed that irradiation with a fluence of F = 3.24 × 1010 cm−2 leads to an increase in the perimeter and area of the copper-film delaminations formed upon penetration of the indenter. This indicates a β-induced reduction in adhesion in the Cu/Si structure.

Nickel galvanochemical coating modified by carbon nanotubes

The structure and microhardness of a nanocomposite nickel galvanochemical coating formed with Watts electrolyte and containing 60 mg/dm3 carbon nanotubes are studied. An addition of carbon nanotubes to the electrolyte leads to a substantial modification of the morphology and texture of grains, grain refinement, and an increase in the coating microhardness by 40%.

Morphology and growth kinetics of Ni nanoparticles on the surface of multiwalled carbon nanotubes at galvanostatic electrodeposition

Nickel nanoparticles are obtained by galvanostatic deposition on the surface of multiwalled carbon nanotubes. The growth kinetics and morphology of Ni nanoparticles for current densities j ranging from 0.01 to 5.00 A/dm2 are investigated.

Phase transformations under indenter in silicon bombarded by low-intensity flux of beta particles

The phase composition inside and outside of impressions formed under indentation of silicon in the presence of low-intensity beta radiation is studied. Comparative analysis of obtained spectra makes it possible to conclude that the contribution of phase transformations under indenter during W-shaped variation of silicon microhardness induced by beta radiation is insignificant. Consequently, nonmonotonic silicon softening is caused by the transformation of the point defect (intrinsic and radiation-induced) subsystem in conditions of low dislocation mobility at room temperature.