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Research has been done on the microstructure, lattice parameters, and tribological characteristics of materials based on silicon carbide. It has been found that the most promising material from the viewpoint of tribology is silicon carbide made with phenol binding agent.Recently, ceramics have been widely recognized as a new class of advanced materials with a high level and unique combination of physicomechanical characteristics, which differ favorably from metals and alloys [1]. The strong ceramic based on silicon carbide is a promising tribological material, since it has good mechanical and thermophysical properties, as well as stable hardness and strength over a wide temperature range [2, pp. 108 -128]. Materials based on SiC are used in the aerospace, defense, metallurgical, and general engineering industries, as well as in chemical engineering and medical technology [3]. At the Technology ONPP, research has been done on the general and physicomechanical properties of components made from reaction-bonded silicon carbide after tribological tests [4].To perform the tests whose results are given here, blanks were prepared by semidry pressing with initial density 2.05 g/cm 3 . After pressing the blanks were annealed in a cover of wood charcoal, which reduced the carbon loss, and correspondingly produced reactive sintering with a lower free silicon content. The maximum preliminary firing temperature was 900EC with a rate of increase of 250EC/h, hold time at maximum temperature 3 h.A pyramid of blanks was laid out on a support of silicon carbide covered by carbon fibers for siliciding. At the top of the pyramid there was a crucible containing silicon carbide with a silicon content constituting 0.7 of the blank mass. The maximum siliciding temperature was 1615°C with a rate of increase of 400°C/h and a hold at the maximum temperature of 1.5 h. Five specimens (Nos. 1 -5) were used in examining the general and physicomechanical properties. Specimen No. 1 had a basic charge composition: a mixture of SiC powder, carbon black, and starch binder, with the specimen covered by a diamond-type layer. The other specimens differed from No. 1 as follows: in No. 2, the charge was doped with boron compounds; specimen No. 3 was made with a phenol binding agent; No. 4 additionally contained nanodiamonds in the charge; and No. 5 additionally had nanopowder of finely divided technical carbon in the charge.The apparent density and open porosity were determined by water uptake: the mass of a dry specimen was determined by weighing in air, while the pore volume was determined by weighing a specimen saturated with water; and the specimen volume was determined by hydrostatic weighing. The Vickers microhardness was determined with a PMT-3M instrument. The method was based on indentation with a diamond tip in the form of a regular four-faced pyramid under a load applied for a certain time, with measurement of the diagonals on the indent remaining after relieving the load. Table 1 gives the physicomechanical properties of the specimens.In the...

Trends in research performed by FGUP ONPP Tekhnologiya in the area of nanotechnologies are described. Results of developments have been introduced into the manufacture of articles in the aviation and rocket and space industries as well as new thermal insulation materials (TIM-MP) which may be employed in steel and alloy casting units and in industrial furnaces.For more than 15 years FGUP ONPP Tekhnologiya has conducted studies in the area of nanotechnology and has now achieved major practical results that have been introduced into the manufacture of products for the aviation and rocket and space industries as well as for other purposes and the characteristics of these products have been substantially improved. Studies have been performed in a number of areas.The first area of study in the field of nanotechnology is the creation of thin film coatings for structural and instrument optical equipment. The physical principle in the regulation of the optical properties of articles by means of modification of their surface entails the use of the process of interference of electromagnetic waves. In most cases the coatings of optical filters are of a thickness that is a multiple of a one-fourth of the wavelength of radiation which we wish to reduce to a required level. For the visible band of radiation this is in the range 10 -125 nm. Different types of optical light filters may be created by varying the number of layers with different indices of refraction and different thicknesses of these layers.A group at ONPP Tekhnologiya has developed an industrial technology for use in application of glazing made of silicate and organic glass to articles through the use of the method of cathode magnetron sputtering of multifunctional nanocoatings 3-10 nm in thickness (Fig. 1). This has made it possible to achieve a 3 -4-fold reduction in the action of electromagnetic radiation on staff personnel and instrument equipment, a 40% attenuation in the thermal flux of solar radiation in the range of wavelengths 0.9 -2.5 mm, improve optical and anti-flash properties through a decrease in the reflectance from the surface of glass in the visible band of wavelengths from 400 to 740 nm, and substantially increase the abrasive resistance and silver and moisture resistance as well as the thermal stability of the optical and strength characteristics of glazing. Glazing articles with the newly developed coatings have been incorporated into new aircraft models (MiG-29K, Su-ZOMKI, Su-35, and the Ansat and Ka-62 helicopters). The capabilities of nanocoatings will grow with the development of a technology for the creation of increasingly thinner layers for an ever-widening range of materials.The first successful experiments in the creation of packing material with a nanocoating of particular substances that

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