№8 2022

  • 1
    Toloraya V.N., Ostroukhova G.A.

    Deals with the issues of determining and evaluating the crystallographic orientation (CGO) of single-crystal castings from nickel heat-resistant alloys obtained by the method of directed crystallization. The methods of setting the axial and azimuthal CGO in castings using seed crystals (seedings) from alloys of the Ni–W system are described. Presents methods for obtaining castings of turbine blades with a single-crystal structure of a given spatial orientation , which allows significantly reducing the level of thermal stresses for cooled blades.

  • 2
    Selivanov A.A., Tkachenko E.A., Babanov V.V., Astashkin A.I.

    The article presents the results of a study of the surface quality of cladding sheets made of alloys of the D16ch type. Methods of metallographic and fractographic analyzes have shown that the appearance of bubbles in the investigated sheets is caused by the presence of internal interfaces (in the form of pores in the base of sheets and cladding), as well as defective areas of poor-quality welding of the cladding and production and heat treatment of sheets, diffuses hydrogen dissolved in the metal or formed on the surface of the sheets during the reaction of aluminum with water vapor. A tendency towards a decrease in the relative elongation in sheets with surface bubbles compared to sheets without defects was revealed.

  • 3
    Kondrashov S.V., Solovyanchik L.V., Minaeva L.A.

    A significant reduction in the percolation threshold of carbon-containing particles in thermoplastic composites can be achieved by distributing the functional filler not over the entire volume of the composite, but only in its part. Regulation of the forces of interaction of functional particles with each other and polymer phases, as well as polymer phases among themselves, by choosing a filler, its covalent and non-covalent modification, as well as the composition of the polymer mixture is an effective tool for obtaining thermoplastic composites with a given level of functional properties.

  • 4
    Tkachuk A.I., Lyubimova A.S., Kuznetcova P.A.

    This paper provides an overview of the development of plant-based epoxy resins. The review presents the main types of plant raw materials; the methods of obtaining epoxy resins based on vegetable raw materials are listed; general factors influencing the yield of the target product are identified: reaction temperature, concentration and type of organic acids. Based on the studied literature data, it can be concluded that the production of plant-based epoxy resins will become a topic for promising research and development of additives for adhesives, paints or composite materials in the future.

  • 5
    Sedova L.S., Dolgova E.V.

    The article contains information about hydraulic fluids used in the foreign and Russian aviation at the present time. Brief information about hydraulic systems is given. Information is provided on foreign hydraulic fluids such as Skydrol™ and Hyjet™ and domestic working fluids named NGZh-5u, LZ-MG-2, 7-50S-3 and hydraulic oils of the MGE-10A, AMG-10 brands. The main Russian enterprises engaged in the production of hydraulic fluids over the past 40 years are indicated. Information on modern developments of hydraulic fluid compositions in the Russian Federation is presented.

  • 6
    Vakhrusheva Ja.A., Yumashev O.B., Chaykun A.М.

    The article is devoted to the analysis of current trends necessary in the creation of rubber compound formulations for special-purpose rubber products, operable under conditions of prolonged exposure to low temperatures. The main operational characteristics of rubbers based on polar and non-polar rubbers are given. The results of new research by scientists from the National research center «Kurchatov institute» state research center of the Russian Federation on the creation of elastomeric materials for work under conditions of prolonged exposure to negative temperatures are systematized, the features of creating frost-resistant rubber are described, and an analysis of the main options for choosing the required ratio of rubbers and ingredients is carried out.

  • 7
    Lebedeva Yu.E., Shchegoleva N.E., Gulyaev A.I., Turchenko M.V.

    The effect of graphene content on the physical and mechanical properties and oxidative resistance of samples of ceramic composite material (CCM) obtained by hot pressing has been studied. The introduction of graphene in an amount of 1–2 vol. % led to an increase in the microhardness of CMC from 24,8 to 26,5 GPa, a decrease in open porosity from 0,8 to 0,2 %, and an increase in oxidation resistance at a temperature of 1500 °C by 63 %. . The structure of graphene with a hexagonal crystal lattice was studied by scanning and transmission electron microscopy: graphene has a scaly fragmentation structure with agglomerate sizes from 1 to 8 μm.

  • 8
    Startsev V.O.

    The influence of aviation fuels, oils and technical fluids on the mechanical properties of polymer composite materials is considered. Regularities of aging in water and aqueous solutions of acids, bases, salts are analyzed. It is shown that the reasons for the change in properties are the processes of plasticization, destruction and post-curing of polymer matrices, chemical destruction of reinforcing fillers and adhesive interaction at the «matrix–filler» interface, the formation of microcracks under the action of internal stresses, enhanced by the action of water and aqueous solutions of acids, salts and bases.

  • 9
    Slavin A.V., Silkin A.N., Grinevich D.V., Yakovlev N.O.

    Considers composite materials with a 3D-reinforced structure. A review of the main options for materials according to the manufacturing method was carried out: woven, knitted, braided and with through reinforcement, as well as woven with a multiaxial fabric and woven with a distance. 3D-reinforcement allows you to increase the shear strength, resistance to delamination and impact. However, it also reduces other mechanical properties by damaging or distorting the horizontal fibers. The most promising for use in load-bearing structures are 3D-woven composite materials due to the least destruction of fibers.

  • 10
    Kolobkov A.S.

    Currently, interest in carbon fibers and polymer composite materials based on them, which are promising materials, is quite high. The article discusses the emergence of carbon fiber technology and its development. Technologies for obtaining a precursor from polyacrylonitrile, from which carbon fibers are produced, are described. The main directions of their improvement are shown, as well as possible ways of developing carbon-based fibers and their main manufacturers.

  • 11
    Vlasova O.V., Solntsev St.S., Denisova V.S., Lepschikov V.G.

    In this work technological coatings based on glass-forming systems K2O–BaO–SiO2 and Na2O–BaO–SiO2, used to protect zirconium alloys from oxidation during hot deformation was studied. Among 12 synthesized compositions a composition was selected with such a ratio of base glass components and modifying additives that provides a dense glassy visible coating on samples of zirconium alloys, prevents rapid increase in microhardness in near-surface layer of metal and effectively protects material from changes in mass during heating for deformation and prolonged excerpts.

  • 12
    Podzhivotov N.Y.

    The application of the method of single-factor analysis of variance is considered on the example of evaluating the results of mechanical tests of a metallic structural material (aluminum alloy). Analysis of variance is proposed to be used as a simple but effective method for the rapid assessment and/or control of the levels of material properties based on the results of physical and mechanical tests, as well as for the assessment and control of the uniformity and stability of experimental data obtained during circular interlaboratory or qualification tests.