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Transmission electron microscopy has been used to study the structural features of boron carbide treated in a high-pressure shear chamber with diamond anvils in the pressure range 25–55 GPa. Such a treatment has been shown to lead to the predominant crack formation along planes {10 11 } and {10 12} and also the formation of polytypes in the {10 11} planes and strain bands in the {10 12} planes.

A new type of ceramics based on the phases of fullerite derivatives and boron carbide B4C is obtained. The material is synthesized at a temperature of 1500 K and a relatively low pressure of 4 GPa; it has a high hardness of 45 GPa and fracture toughness of 15 MPa m1/2.

A new fully carbon nanocomposite material is synthesized by the immersion of carbon nanotubes in a fullerene solution in carbon disulfide. The presence of a dense layer of fullerene molecules on the outer nanotube surface is demonstrated by TEM and XPS. Fullerenes are redistributed on the nanotube surface during a long-term action of an electron beam, which points to the existence of a molecular bond between a nanotube and fullerenes. Theoretical calculations show that the formation of a fullerene shell begins with the attachment of one C60 molecule to a defect on the nanotube surface.

Results of examination of the effect of modifying the grain boundaries of nanostructured corundum with carbon nanoclusters on the nanocomposite hardness are reported. The nanocomposite hardness was found to be increased to 28 GPa. This value is substantially higher than the hardness of single-crystal corundum at any crystallographic plane (23 GPa). Carbon was present at grain boundaries in the obtained nanocomposite owing to the fact that this nanocomposite was sintered from clusters containing corundum nanograins coated with several C60 layers. The structure of samples was investigated by transmission electron microscopy and Raman spectroscopy, and their hardness was measured by indenting and scratch testing.

The method and results of synthesizing carbon nanotubes and onion-like structures by the sublimation of a mixture of a carbon powder with a catalyst (Y2(CO3)3) in the plasma flow of an inert gas (argon) generated in an rf plasmatron are described. Carbon vapors are condensed into fullerene-containing soot onto various materials (Al, Cu, Ti, stainless steel) placed in the working chamber of an experimental setup. The composition of the synthesized soot is analyzed by modern highly informative methods (Raman spectroscopy, transmission electron microscopy, X-ray diffraction). Single-wall carbon nanotubes of a small diameter (1.2 nm) and onion-like structures 10–20 nm in size are formed in experiments. In a reference experiment on a mixture of argon and methane, a material, which consists of a mixture of amorphous carbon, nanosized graphite, and graphite with a crystallite size of several microns, is synthesized. The effect of the substrate material, the gas pressure, and the plasma flow velocity on the formation of carbon nanotubes is studied.

The modification of transport properties (thermal conductivity, electrical conductivity, and See-beck coefficient) of nanostructured thermoelectrics based on Ge and Si-Ge with inclusions of the second phase has been investigated experimentally. In the Ge-C60 nanocomposite, modifying inclusions are the fullerene C60 located along the germanium grain boundaries and 1- to 5-nm SiC nanocrystals in the Si-Ge-SiC nanocomposite. In particular, the presence of these inclusions in the nanocomposite leads to an increase of the Seebeck coefficient in the temperature range above 600 K and, in general, to an increase in the thermoelectric figure of merit ZT by a factor of 1.5–2 as compared to the corresponding characteristics of nanostructured thermoelectrics based on Si-Ge without modifying inclusions of the second phase.

The results of synthesis of carbon onionlike nanostructures from methane in plasma flow of inert gas (argon) generated in induction high-frequency plasmatron are considered and discussed. Carbon vapor obtained via dissociation of methane in plasma flow was condensed on copper substrates placed in a working chamber of the setup. The content of the synthesized soot was analyzed using scanning and transmission electron microscopy. As a result of the performed experiments, carbon onionlike structures with 20- to 100-nm sizes were obtained.

The Hugoniot elastic limit and the spall strength of aluminum and copper samples pressed from a mixture of a metallic powder and 2–5 wt % C60 fullerene powder are measured under a shock loading pressure up to 6 GPa and a strain rate of 105 s−1 by recording and analyzing full wave profiles using a VISAR laser interferometer. It is shown that a 5% C60 fullerene addition to an initial aluminum sample leads to an increase in its Hugoniot elastic limit by an order of magnitude. Mixture copper samples with 2% fullerene also exhibit a multiple increase in the elastic limit as compared to commercial-grade copper. The elastic limits calculated from the wave profiles are 0.82–1.56 GPa for aluminum samples and 1.35–3.46 GPa for copper samples depending on the sample porosity. The spall strength of both aluminum and copper samples with fullerene additions decreases approximately threefold because of the effect of high-hardness fullerene particles, which serve as tensile stress concentrators in a material under dynamic fracture.

A nanocomposite material consisting of Bi2Te3 nanocrystals 30 nm in size coated with a C60 molecule layer is obtained. The Hall effect and thermoelectric properties of the composite are studied. The acceptor effect of fullerene in both p- and n-type Bi2Te3 is detected. Nanocomposite material properties are modified due to the formation of layers of fullerene charged molecules: the nanocomposite thermopower increases, while the thermal conductivity decreases.

A method has been developed to measure the hardness of superhard materials with an atomic force microscope. By using an indenter made of ultrahard fullerite C60, of hardness superior to that of diamond, plastic deformation of diamond is achieved at room temperature without any crack formation and its hardness is measured.