Differences of the effect of thermal treatment in an oxygen-containing gas medium on properties of the surface layer Ti, Zr, Hf

The paper presents the characteristics of the surface layer of d-elements of the IV group (titanium, zirconium and hafnium) after thermal diffusion saturation from a controlled oxygen-containing gas medium. Saturation was carried out at = 750 °C for t = 5 hours at different pressures (P = 1.33∙10–1 Pa, = 1.33∙10–2 Pa, P = 1.33∙10–3 Pa). Experimentally revealed differences in the characteristics of the surface layer of titanium, zirconium and hafnium.

Microstructure and microhardness of nickel-base heat-resistant alloys obtained by directional and equilibrium crystallization

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.

Optimization of Welding Modes for High-Strength Low-Alloy Domex 700 Steel

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.

Perspectives of Method Atomic Force Microscopy for Research and State Physical and Mechanical Characteristics Precision Machinery Surface Products

This paper is the well-proven expediency of the use of method of atomic-force microscopy is at research of the state and superficial descriptions of surfaces of wares of precision engineer. Basic directions of researches of topogram, physics and mechanics descriptions of surfaces of wares of precision engineer and set limitations and defects are considered in using of its method for research of separate properties of surfaces of wares.

Мікротвердість поверхневих шарів гартованого склах

The value of microhardness of the surface layers of 6 mm float glass, tempered by contact and by air method by etching in a mixture of fluoride and sulfuric acids, is researched. It was established that the microhardness value depends on the method of tempering and thickness of the etched layer. The optimal parameters of the microhardness measure of 6 mm float glass are selected and thickness of the etched layer which causes the relaxation of residual tensions is indicated.

Ефективність впливу захисного покриття на експлуатаційні властивості бетону

The article is devoted to development of theoretical foundations of improving corrosion resistance of concrete protective coatings based on filled with aluminum and zinc oxides polimetylfenilseloksanu. Methods of mathematical experiment planning with regard to water absorption depending on the concrete and coating adhesion strength optimum component of the original compositions for protective coatings, determined their technological and physical and mechanical properties, the thickness of the coating, application methods and the surface of the concrete conditions of the studied.

Залежність величини мікротвердості 6 мм листового флоат-скла від умов її визначення

The change of microhardness values of 6 mm float glass, depending on the measurement conditions were investigated. It was established that the value of microhardness depends on the surface moisture, the load on indentor and duration time. The optimal parameters of microhardness measurement of 6 mm float glass were chosen. 

Modification of surfaces of special alloys by nitrogen for power engineering

The use of nitrogen as an alloying element presents a great interest for the improvement of properties of alloyed steels and special alloys. Superficial layers were formed by ionic implantation and by melting the surface by nitrogen plasma. After this kind of treatment, there form a continuous defect-free layers with a good adhesion to the surface. Surface treatment of steels and vanadium alloys increases their corrosion resistance and microhardness of surface layers.

The structure, mechanical and electrophysical properties of monocrystalline silicon under influence of constant magnetic field

The monocrystalline silicon is one of the most important materials in the view of the fact that it is used in contemporary electronics. The issues concerning silicon processing methods up to now attract a lot of attention of scientists all around the world. From this point of view, the influence of constant magnetic field upon the monocrystalline Czochralski silicon had been studied. The processing of monocrystalline Cz-Si (alloyed with Zr, Hf, Mg, Al, and unalloyed) in weak constant magnetic field (0.07 Tesla) has been carried out.

Influence of Polymerization Conditions on the Microindentation Properties of Poly(allyl(p-allylcarbonate)benzoate)

Flat plates of poly(allyl(p-allylcarbonate) benzoate) obtained via photopolymerization and thermal polymerization have been studied by means of microindentation. The plates were about 3 mm thick. The values of microhardness (MHV)/total microhardness (MHT) have been determined. Accordingly, structural changes in the plate bulk due to the polymerization method were detected. The plates obtained by photopolymerization possess a superficial layer harder than the inner layers and its thickness is not uniform.