№4 2015
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1
The investigation results of the new weldable wrought alloy V-1208 based on Al–Cu–Mn system with addition of Sc, Ag and Zr are represented. Sheets from this alloy were manufactured at JSC «KUMW». It was shown that scandium, silver and zirconium complex additions increase strength and life-time characteristics, corrosion resistance and weldability. Influence of heat treatment modes on the sheets mechanical properties was studied. Complex investigations of mechanical, corrosion and operational charac-teristics are represented. Weldability with argon arc welding and friction stir welding are evaluated. Comparison with 1201 and 2219 alloys is carried out.
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2
Current development and research trends in the field of producing and investigating of long-life heat-resistant coatings for nickel and titanium alloys with working temperature up to 1000°C are considered. The results of investigations currently taken place and the ways of improving the properties of long-life enamel coatings are shown. The FSUE «VIAM» experience on the heat-resistant coatings development capable to provide long term effective operation of the nickel and titanium parts in high operational temperatures is considered.
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3
The matter of amorphous metal bands application in the laminated metal-polymeric functional components (actuators) for smart materials is hereby considered. The remarkable feature of the metal amorphous materials is their structural and chemical homogeneity, high plasticity and their resistance to repeated bending and corrosion. It is suggested to use the amorphous metal materials as bands in conjunction with ferroelectric ceramics made of lead zirconium-titanate to create laminated piezoelectric cells. Phase transformation process in nickel-based amorphous alloy VPr51 of metal-metalloid type by means of differential scanning calorimetry and thermo-mechanical analysis methods is studied as well. It is determined that the given nickel-based amorphous alloy keeps its structural homogeneity and workability in the temperature range up to 380°C relevant to the piezoelectric materials based on lead titanate-zirconium operation.
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4
The method of raster electron microscopy and the fractographic analysis was applied to research surface and microstructure of heat resistant nickel alloys samples before and after destruction in order to identify pre-destruction signs after tests for short-term and long-term hardness and also for low-cyclic fatigue at temperatures of 20, 650 and 750°С. It is determined that exits density of slip planes on surface of studied samples depends on testing method, level of applied load and temperature of tests, there are differences in behavior of alloys during the loading. Difference in resistance to slip systems development and to destruction start after exhaustion of material ability for plastic deformation is shown for two alloys.
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5
The complex thermal barrier coating (TBC) for rotor blades of jet prop engines made of nickel-base superalloy VZHM4 working at temperatures up to 1200°С is represented, and also application of high-temperature heat resistant coatings for intermetallic nickel-base alloys as a bond coatings for turbine nozzle blades working at temperatures up to 1250°С is considered. Results of high-temperature tests of VZhM4 and VKNA-25 alloys with applied TBC are represented. It is shown that [Ni–Cr–Al–Ta–Re–Y–Hf+Al–Ni–Y]+(Zr–Y–Gd)O TBC protects VZhM4 alloy at temperatures up to 1200°С and [Ni–Cr–Al–Hf+Al–Ni–Hf]+(Zr–Y–Gd)O HPC protects VKNA-25 alloy at temperatures up to 1250°С. Research of thermal conductivity of ceramic (Zr–Y–Gd)O material is made.
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6
It was determined that the maximum level of strength is achieved after full heat treatment (quenching and artificial ageing) after welding. Heat treatment of welded joints made by friction stir welding leads to structural heterogeneity alignment and removal of weakening of the heat affected zone. After-welding modes of heat treatment do not practically influence the protective properties of non-metallic inorganic coatings.
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7
The article considers advantages and disadvantages of currently used ZrO2–(7–8)%Y2O3 (yttrium-stabilized zirconia – YSZ) ceramic layer, widely used now in serial coatings to protect turbine blades of gas turbine engines. The systems and some properties of new ceramic materials based on zirconium oxide with the addition of one or more rare earth elements which are currently being developed abroad are represented. The ceramic layers developed by VIAM brought on by magnetron midrange targets sputtering based on zirconium alloys with rare earth metals with following plasma chemical ceramics deposition in the argon oxygen environment are shown. The microstructure of the surface of the deposited layers, thermal conductivity and the prospects of their use in the development of a new thermal barrier coating (TBC) generation are investigated.
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8
The possibility of using ion-plasma coatings deposited by high energy vacuum-plasma technology to reduce the free end oscillations amplitude of VT6 titanium alloy samples during testing on vibrodynamic bench at resonance conditions by the first bending mode is hereby shown. The coatings based on pure Ti, Zr, Cr, Ni, Al, Cu metals deposited on the MAP-3 unit under modes enabling the coating growth in the range of 19–73 g/m2 while the tempera-ture of ion and radiation heating does not exceed tempering temperature of the VT6 titanium alloy is investigated. The tests on the damping capacity of applied coatings were performed. It is established that aluminum coating has the best properties.
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9
The physical, mechanical and thermo-physical properties of the domestic foamed elastic VPP-1 and rigid plate-type VPP-5 polymer materials produced to substitute the foreign foamed elastic «Solimide» (USA) and rigid plate-type «Rohacell» (Germany) polyimide materials are described in the article. Properties of the domestic foamed VPP-1 and VPP-5 polyimide materials are compared with foreign foamed polyimide analogue materials. The description of the manufacturing method for the foamed polyimide test specimens on the foamed polymeric materials mechanical treatment equipment developed in VIAM is provided. The recommendations on application of the domestic foamed polyimide materials VPP-1 and VPP-5 are given as well.
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10
In this work the anti-corrosion properties of polyesterurethane compound in conditions of high humidity (WKL-100) and the salt spray chamber (KCT-35) on samples of 30KhGSA steel and D16-T, 1163-AT and 1163-T aluminum alloys were determined. The results were compared with properties of well-known Cor Ban 35, PINS AT (TU38.401-58-120–95) and Dinitrol AV-40 protecting compounds. The fulfilled tests have shown high protective properties of pilot batch of PEUK compound for application in technological processes for enhanced parts and units protection in aviation hardware.
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11
On the investigations examples of aircraft gas turbine engines corrosive damages after 5 years exposure on the open experimental ground of the FSUE «VIAM» G.V. Akimov Gelendzhik climatic test center (VIAM GCTC) the possibilities of confocal laser imaging microscopy are represented. The 3D-models were built and quantitative assessment of surface topography by statistical data processing of the roughness using standard software was undertaken.
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12
The method of determining the adhesion strength of silver coating to the silicon substrate was developed for defining the quality of contact connections in semiconductor elements. It is shown hereby that the best option is to use high-adhesive membranous glue VK-51 and a special tooling with molybdenum heat compensators.
