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Uglev N.P., Poilov V.Z., Smirnov S.A., Zvezdin V.L., Shilov A.V. Distribution of complex alloys components in the volume of a metal casting
Investigated was the distribution of component concentration near casting walls for 10 grades of high-temperature nickel alloys for aircraft application. It was shown that for alloys having a dendritic structure the concentration deviations from the mean value amount to 67% and have a wave character with a step exceeding the dendritic net period by one order of magnitude. Investigated were the regularities of forming a modified metal layer at boundary between the casting and the ceramic mold (burn-on). It was shown that in the scale of investigated castings (210 mm) there is no thermogravitational convection in the melt. Analysis of structural features and data on the distribution of components in the surface layer of the castings made it possible to formulate a hypothesis about the causes of burn-on formation as a consequence of the movement of flows of particular melt atoms being in a special superfluid state.
Key words: Heat-temperature alloys for aircraft application, nickel-based alloys, concentration distribution, dendritic structure, thermogravitational convection, burn-on, alloying components, melt macrostructure, microconvection.

Khristenko V.V., Ushkalova O.V. Results of investigating wear-resistant chromium irons
The possibility of Cu-Fe-Cr-C melts existence in two liquid phases form copper based and Fe-Cr-C-phases has been experimentally confirmed by methods of sedimentation analysis and differential scanning calorimetry. Dispersed in (Fe-Cr-C) melt copper phase inclusions, are obstacles to growth of primary carbides during solidification wear resistant chromium cast iron and provide primary carbides reduction.
Key words: Wear resistance, chromium iron, two-phase melt state, frozen emulsion, copper phase, thermographic curves.

Batyshev A.I., Batyshev K.A. Formation of hot tears in steel castings depending on solidification conditions. Part I. Set forth is information about some peculiarities of solidification and cooling of grade 25L GOST 977-88 steel in molds with different heat accumulation capabilities, change in linear shrinkage and hot tearing in castings. In Part I of the article, considered are conditions of solidification and cooling in disposable (sand, shell, chamotte) and metal molds. Presented are cooling curves of experimental castings with a diameter of 30 mm, curves of temperature distribution across their cross-sections, skin growth in time.
Key words: Casting, carbon steel, solidification, cooling, molds, cooling conditions.

Stotzel R., Yilmaz I., Liu S., Kimura F. Use of refractory coatings and additions to produce castings without defects and impurities
ASK Chemicals has been able to develop new type of additives which enable the foundries to reduce the casting defects significant and cast more cores uncoated. ASK developed within the framework of a development project different extremely gaspermeable coatings which suppress these defects. The new coating, which fulfils this profile, is the Miratec AH 501. Due to the fact, that the water jackets for motor blocks or oil galleries are almost impossible to shot blast, there is a serious demand on the coatings to provide flawless castings but also zero adherence of the coating on the casting surface. A special coating based on good anti-veining and anti-penetration properties have been developed, which reduces the coating residue after pouring to a minimum. SEM investigations show that the coating has self-releasing properties after pouring.
Key words: Mould and core coating, sand additives, foundry, performance, casting defect.

Konunnikova S.G., Zhukebaeva T.Zh., Aubakirov D.R. Compositions and methods of forming dispersed resin-bonded sands
The paper considers different compositions of sand-resin mixtures and solutions on improvement of their physical-mechanical properties. There also was shown the relationship between technological parameters of mixtures, compositions and properties of the binder components of mixtures. Results of mechanical testing of castings obtained with the use of mixtures of different composition. It describes experimental unit for manufacture of shell molds from sand-resin mixtures. Finally there was defined an optimum composition of the core mixture for manufacture of radiator cores.
Key words: Sand-resin mixture, binder, model, form, stem, pulver bakelite, phenolformaldehyde.

Zaitsev V.M., Malinovsky V.S. Modern equipment by NTF EKTA for resources-saving ecologically clean technology of melting high-quality metals
The article attempts to answer the question: which is more advantageous when creating or reconstructing plants to develop the Russian industry and technologies basing on innovative domestic developments, or to buy foreign ones often considerably inferior to the domestic ones by their characteristics? On concrete examples, shown is the high efficiency of versatile DC arc furnaces (DPPTU-NP) developed by NTF EKTA, the results of whose adoption and industrial operation, by the basic indices, are superior to both domestic and foreign counterparts.
Key words: Melting equipment, melting furnaces, DC arc furnaces, melting system, melting steel and alloys, scrap recycling, ecology, high casting quality.




Table of content

Uglev N.P., Poilov V.Z., Smirnov S.A., Zvezdin V.L., Shilov A.V. Distribution of complex alloys components in the volume of a metal casting

Khristenko V.V., Ushkalova O.V. Results of investigating wear-resistant chromium irons

Batyshev A.I., Batyshev K.A. Formation of hot tears in steel castings depending on solidification conditions. Part I.

Stotzel R., Yilmaz I., Liu S., Kimura F. Use of refractory coatings and additions to produce castings without defects and impurities

Konunnikova S.G., Zhukebaeva T.Zh., Aubakirov D.R. Compositions and methods of forming dispersed resin-bonded sands

Lisovoy A.A., Gorbacheva N.A., Minkina O.Y. Problem solution - Vibrating Sand Spiller

Zaitsev V.M., Malinovsky V.S. Modern equipment by NTF EKTA for resources-saving ecologically clean technology of melting high-quality metals

Panov A.G. On the issue of development strategy for domestic foundries




July 2017


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, 2017
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