In order to determine the safe operational life of the components of gas turbine engines (GTE), introductory tests of nickel-base heat-resistant alloys (NHRA) have been performed. X-ray fluorescence and X-ray diffraction analyzes, optical microscopy and Vickers hardness measurements provided data on the phase-structural state and mechanical properties of the pristine ZhS6K-VI and ZhS32-VI alloys obtained by equilibrium and high-speed directional crystallization, respectively.
The article deals with major problems, which have arisen in compiling process of electronic multilingual dictionary of dental terms. The article gives a detailed analysis of developing macro-, medio- and microstructure for the abovementioned dictionary and some lexicographical parameters are considered. Some aspects of dictionary entries writing and software for dictionary compiling are highlighted as well.
The influence of iron sulfides created on 0.45%C steel and microstructure of this steel
on hydrogen overvoltage was investigated. It was shown, that iron sulfides on the surface of
0.45%C steel, usually, decrease hydrogen overvoltage of hydrogen depolarization. The
greatest effect was created by the cansite films. Corrosion of ferrite-perlite microstructure
passes under anode control. Corrosion of troostite microstructure passes under mixed
cathode-anode control, and for sorbite and martensite microstructures it passes under cathode
The microstructure and hardness of the weld joints of DOMEX 700 steel were investigated. As a result, the optimization of the parameters of robotic arc welding in the environment of protective gases was carried out taking into account the size of the energy per unit length. The optimum modes of welding were determined. The size of the deterioration area, where there is a decrease in hardness in comparison with the main metal, for a thickness of 6 mm is 2.36 mm, and for a thickness of 3 mm is 1.51 mm.
The effect of carbonate additives on physical and mechanical properties of type II Portland cement was investigated. It was shown that calcium carbonate which is added as fine ground mineral additive, participates in the phase composition and microstructure formation of Portland composite cement paste.
The principles of creating of multimodal composite Portland cements with optimized void filling, that based on synergistic combination of ultrafine active mineral additives with superplasticizer were established. The optimization of multimodal multicompositе Portland cements was carried out and the relationship between the phase composition, microstructure and strength of the cement matrix were investigated.
The physico-chemical methods of the research of hydrated cement by mechanoactivated bonding substance with organo-mineral additive (microsilica + C-3) was presented. It was explored the influence of the additive into the kinetics of formation lowly basic calcium hydrosilicate.
In this paper prescriptions of dry building mixes for industrial floors were developed. Main indicators for such material are enough spreadability of fresh mixture during certain period of time, needed for its enclosing, high early strength, minimal deformation of hardened material. Technology of industrial floors construction in buildings with high loading is showed. Investigation of quartz sand with different granulometry on physical and mechanical properties of dry building mix for industrial floors is conducted.
Finishing mortars for decorative and protective facade coatings where natural kaolin is a major component were developed. The chemical and phase composition and microstructure of kaolin were investigated. Ultrafine kaolin (SSA = 1,58 m2/g) actively participates in the formation of phase composition and microstructure of the cement matrix of finishing mortars. Nanoscale systems of clay minerals due to plasticizing effect and filling influence provide improved adhesion-cohesive properties of finishing mortars.
The article examines the features of hardening and structurization processes of cement with high-energy self-tension. The physical-chemical methods of the research confirm that the use of the granulated expanding additive leads not only to an increase in expansion but also proves to form zones with different hydrated phases around granule