Aluminum matrix composites reinforced with multiwalled carbon nanotubes (MWCNTs) are promising materials for applications in various high-tech industries. Control over the processes of interfacial interaction in Al/MWCNT composites is important to achieve a high level of mechanical properties. The present study describes the effects of coating MWCNTs with titanium carbide nanoparticles on the formation of mechanical properties and the evolution of the reinforcement structure in bulk aluminum matrix nanocomposites with low concentrations of MWCNTs under conditions of solid-phase consolidation of ball-milled powder mixtures. Using high-energy ball milling and uniaxial hot pressing, two types of bulk nanocomposites based on aluminum alloy AA5049 that were reinforced with microadditions of MWCNTs and MWCNTs coated with TiC nanoparticles were successfully produced. The microstructural and mechanical properties of the Al/MWCNT composites were investigated. The results showed that, on the one hand, the TiC nanoparticles on the surface of the MWCNT hybrid reinforcement reduced the damage of reinforcement under the intense exposure of milling bodies, and on the other hand, they reduced the contact area of the MWCNTs with the matrix material (acting as a barrier interface), which also locally inhibited the reaction between the matrix and the MWCNTs.
30 January 2018 in Journal of Physics: Conference Series
The processes of graphene structures formation under the action of the femtosecond laser radiation on carbon samples in liquid nitrogen are discussed. Mechanisms of graphene sheets exfoliation are proposed depending on the power density of the laser radiation: in the first case, the separation occurs due to the volumetric expansion during heating the region occupied by nitrogen molecules; at a laser radiation energy exceeding the ablation threshold, the surface of graphite begins to breakdown in the region of the action, followed by separation into graphene layers.
1 March 2018 in Journal of Surface Investigation: X-Ray, Synchrotron and Neutron Techniques
The possibility of an alternative approach to structure determination based on the methodology of matching the external shape of the obtained samples with a set of layerwise growth polyhedra is...
1 December 2017 in Bulletin of the Russian Academy of Sciences: Physics
Tungsten surface nanostructuring is performed using the radiation of a Yb:KGW femtosecond laser in air and in liquid nitrogen. Arrays of linear nanostructures and nanorods of tungsten and tungsten nit
1 December 2017 in Bulletin of the Russian Academy of Sciences: Physics
Results are presented from experimental studies of the filamentation of femtosecond laser radiation in a transparent medium. Schemes for registering plasma channels of filaments, conical emission, and
1 December 2017 in Bulletin of the Russian Academy of Sciences: Physics
A qualitative model describing the subsurface overheating of carbon samples exposed to femtosecond laser irradiation in liquid nitrogen is proposed for purposes of simulation. To a large degree, the m