Table of contents

The International Conference and youth scientific school "Materials and technologies of new generations in modern materials science" (MT2016) was held at the Institute of High Technology Physics at Tomsk Polytechnic University, June 9-11, 2016, Tomsk, Russia. The conference is devoted to the 120^th anniversary of Tomsk Polytechnic University and the 60^th anniversary of the Department of Materials Science in Mechanical Engineering.

The conference goal was discussing the current issues in materials science, problems and methods of their solutions for creating new materials with targeted properties, development and manufacturing of construction materials, surface hardening and protective coatings, advanced materials and technologies. New approaches and ideas presented in the conference proceedings can find their practical application in enhancing reliability of machine parts and equipment in chemical, energy, building and other industries.

The mains topics of the conference were as follows:

• Problems of strength, ductility and fatigue life of advanced structural materials

• Surface hardening and protective coatings

• Silicate and refractory nonmetallic materials

• Photonic Materials and technologies

The Organizing Committee would like to thank Institute of Strength Physics and Materials Science SB RAS (Tomsk, Russia), Russian Material Science Center (Tomsk, Russia), National Research Tomsk State University (Tomsk, Russia) and Novosibirsk State Technical University (Novosibirsk, Russia) for their participation in the conference organization.

We also appreciate the financial support from the Russian Foundation for Basic Research.

The Organizing Committee of MT2016

Prof. Sergey Panin

Institute of Strength Physics and Materials Science SB RAS, Tomsk, Russia

Tomsk Polytechnic University, Tomsk, Russia

All papers published in this volume of IOP Conference Series: Materials Science and Engineering have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

Modern world trends in the field of energy and mineral resources preservation policy involves the need for a more cost-efficient use of the Earth's natural resources, including in the field of construction industry. Using insulation modern materials would largely solve this problem. The acceptability appraisal of various advanced heat-insulating blankets is a crucial task, which requires experimental verification of total emissivity empirical definition of modern super-thin liquid composite thermal insulators and their real value definition. Method of investigation is as follows: an empirical definition of blankets emissivity using the proposed laboratory equipment, which comprises a system of "gray" bodies, thermocouple probe and a source of continuous heat flux. Total emissivity of modern super-thin liquid composite thermal insulators is experimentally determined. It amounted e = 0.89 for sample # 1, and e = 0.87 for sample # 2 at a temperature of 35-65 °C. It was found that the actual emissivity of the samples was higher than it had been declared.

This paper discusses an approach to prediction of the generation of pouring defects using the example of a technological process of manufacturing GTE blades. A computer-based modeling system for foundry processes, ProCast, was used as a tool for this research. Possible reasons of the formation of defects were considered and the recommendations for their elimination were provided.

The aim of the work is to solve question of accuracy increase in tolled and annealed parts made from forged rod of titanium alloy. Plate pieces were cut from cross-section, annealed at 800°C during 1, 2, 3, 4 and 5 hours. The criterion combining minimum bending radius and spring back angle was found. This criterion shows the maximum values after tooling and annealing for 3 hours.

This paper presents a study of characteristics of an evolution of deformation fields in surface layers of medium-carbon low-alloy specimens under compression. The experiments were performed on the "Universal Testing Machine 4500" using a digital stereoscopic image processing system Vic-3D. A transition between stages is reflected as deformation redistribution on the near-surface layers.

The operating capacity and service life of printed circuit boards in various electronic equipment and devices depends on their ability to resist vibroacoustic loads, including vibration and acoustic noises. In this paper, non-contact laser vibrometry has been applied to perform the modal analysis of a circuit board assembly in order to identify its vulnerable spots and to find solutions to protect the assembly from external vibroacoustic loads. A broadband periodic chirp signal was used to excite vibration, which enabled a rapid generation of results. The paper provides data on eigenfrequencies, vibration velocity fields, and vibration displacement profiles. Frequency ranges have been determined in which eigenfrequencies with the highest vibration amplification lie. The obtained data can be used to develop a quality control technique for printed circuit boards and to optimize their construction as early as the design stage.

Based on an eddy current transducer (ECT), a probe has been designed to research metal-dielectric structures. The measurement procedure allowing one to detect defects in laminate composites with a high accuracy is described. The transducer was tested on the layered structure consisting of paper and aluminum layers with a thickness of 100 μm each in which the model defect was placed. The dependences of the ECT signal on the defect in this structure are given.

The article describes the results of experimental studies on ultrasonic stabilization of the bearing rings. The mean and root-mean-square values of non-roundness of the rings after ultrasonic and thermal treatment were compared. Comparative analysis showed that the root- mean-square deviation and the mean value of non-roundness after ultrasonic stabilization was lower than that after thermal stabilization.

The aim of this work is the stress-strain analysis of bulkhead partition made of carbon fiber reinforced plastic (CFRP) at mechanical testing. The problem was solved in a general 3-D statement for an anisotropic elastic body. The strength prediction of the construction was done by stress analysis in each ply of composite laminate. The numerical simulation was obtained with ANSYS Workbench software. The detailed ply-by-ply stress analysis with special attention to areas of plies curvature was done. The results of numerical simulation were compared with the test data for verification of the proposed numerical algorithm.

The paper deals with the investigation of Lamb wave ultrasonic technique for damage (or mechanical state) evaluation of AA7068T3 specimens in the course of tensile testing. Two piezoelectric transducers (PZT), one of which is used as an actuator and the other as sensor, were adhesively bonded on the specimen surface using epoxy. Two frequencies of testing signals (60 kHz and 350 kHz) were used. The set of static tensile tests were performed. The recorded signals were processed to calculate the informative parameters in order to evaluate the changes in stress-strain state of the specimens and their microstructure.

The article presents the evaluation results of impacts of various strengthening mechanisms to flow stress. Such evaluations were made on the basis of the measured parameters of the dislocation substructure formed in monocrystals of [001]-Ni₃Fe alloy deformed by compression within the stage II. It was found that the main impact to deformation resistance in the alloys with net substructure is made by the mechanism of dislocation impediment, which is caused by contact interaction between moving dislocations and forest dislocations.

The paper presents the results of experimental studies of vibro-mechanical mechanism of residual stresses relaxation in ringed parts. There was described the mechanism of vibro-mechanical relaxation that includes machining of ringed parts among three rotating rolls under pressure. This leads to multicyclic loading due to which there occurs relaxation of residual stresses. To study the process of vibro-mechanical relaxation a complete factorial experiment was carried out. As a result of experiments we obtained empirical dependence of residual stresses on processing factors.

The paper is devoted to study of the impact stress condition and thermomechanical treatment parameters on the structure and texture evolution of new 1565 ph aluminum alloy. For that purposes, we use test on Gleeble equipment, FM calculation, optical microscopy and x ray diffraction texture analysis. The dependency between the deformation texture components development and strain rate value was established. Differences in the texture evolution at uniaxial compression stress and plain strain mode were revealed.

Process of layered structure materials creation based on aluminum alloys is presented. Microplasma texturing method, microplasma oxidation method and chemical metallization method were used to create these structures. Non-conductive nonmetallic inorganic coatings were produced by microplasma oxidation method. Obtained structures showed high durability under thermal stress loads due to substrate metal - non-conductive nonmetallic inorganic coating phase boundary texturing.

The formation of the high-carbon layers on the low-carbon steel (0.18 % C) using the method of electron-beam partial melting of the carbon fibers is considered. A 1.4 MeV electron beam extracted into air was used. The features of the cladded layers formation using different binders for a reliable fixation of the cladding material are studied. It is revealed that the best results are obtained using the phenol-formaldehyde glue as the binder. A 3 mm thickness layers with 2.2 % C are shown to be formed.

The aim of this study was to clarify the effect of the silicon content in steel on the structure of hot-dip galvanized zinc coating. It was found that in steel samples containing the silicon in an amount of about 0.1% and 0.5% the increased thickness coating was formed. This fact was associated with structural features of the ζ-phase. Energy dispersive microanalysis had shown the maximum concentration of silicon in the coating was observed in ζ-phase on St3 steel (Si = 0.1%) and in the fine mixture of δ and ζ-phase on 09G2S steel (Si>0.5%). This phenomenon was analyzed using a Zn-Fe-Si system diagram and its polytermic sections. It was found that there were eutectic reactions of decomposition the liquid to mixture (ζ+η+ FeSi) phases at the content of silicon in steel about 0.1% and more than 0.5%. Particles of FeSi-phase were involved in the dissolution of Г and δ phases, which led to a direct contact of the melt and the steel substrate. This process was accompanied by the intensive ζ-phase formation and the rapid growth of coating thickness.

This paper studies structure of thermal barrier coatings applied to hot gas path components in gas turbine engines and produced in a number of ways, and its impact on performance. Methods of structural reinforcement for ceramic topcoat in thermal barrier coatings are considered.

This paper presents the results of structural investigations and results of tribological and microhardness tests of the coating obtained by electron beam cladding of a Ni-Cr-Si-Fe-B self-fluxing alloy on low-carbon steel. After electron beam treatment high-quality dense layer with a thickness of 1.2-1.8 mm was obtained. The structure of the coating consisted of dendrite crystals based on y-Ni-solid solution and eutectic with complex composition. Microhardness of the coating achieves 370 HV. Wear-resistance of the coating obtained by electron-beam cladding technique was 1.6-fold higher than that of low-carbon carburized steel.

The aim of this study is to investigate the possibility of assessment of the effect of preparatory surface plastic deformation by hydraulic shot blasting on the fatigue strength of cylindrical parts of different diameters (10-40 mm) of D16T alloy with circular notches of semicircular section, based on measurements of residual stress (initial deformations) of a witness sample. The residual stresses of smooth parts were used to calculate the residual stresses of parts with stress raisers. These were used to predict the increment of these parts fatigue limit caused by hardening hydraulic shot blasting. It was found that the highest compressive residual stresses in the smooth parts obtained through calculations differ from the observed values not more than by 7%, and in notched parts by 8%. Using the criterion of mean integral residual stresses, we calculate the increments of the fatigue limit of parts due to superficial hardening. The discrepancy between the experimental and calculated increment values of the fatigue limit of hardened parts with raisers does not exceed 17%.

The paper presents formation of the substrate film system (Zr-Ti-Cu/Al) by electric arc spraying of cathode having the appropriate composition. It is shown that the intense beam radiation of the substrate film system is accompanied by formation of the multi-phase state, the microhardness of which exceeds the one of pure A7 aluminum by ≈4.5 times.

This study considers the structural features of Ni-Cr-Si-B (Ni - base; 15.1 % Cr; 2 % Si; 2 % B; 0.4 % C) materials obtained by different methods. The self-fluxing coatings were deposited by plasma spraying on the tubes from low carbon steel. Bulk cylinder specimens of 20 mm diameter and 15 mm height were obtained by spark plasma sintering (SPS). The structure and phase composition of these materials were investigated by optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffractometry (XRD). The major phases of coatings and sintered materials are γ-Ni, Ni₃B, CrB and Cr₇C₃. We demonstrate that the particle unmelted in the process of plasma spraying or SPS consist of γ-Ni-NEB eutectic and also CrB and Cr₇C₃ inclusions. The prolonged exposure of powder to high temperatures as well as slow cooling rates by SPS provide for the growth of the structural components as compared to those of plasma coatings materials. High cooling rates at the plasma spraying by melted particles contribute to the formation of supersaturated solid solution of Cr, Si and Fe in γ-Ni. The structure of the melted particles in sintering material has gradient composition: the core constituted of Ni grains of 10 μm with γ-Ni-Ni₃B eutectic on the edges. The results of the experiment demonstrate that the sintering material has a smaller microhardness in comparison with plasma coatings (650 and 850 MPa, respectively), but at the same time the material has higher density (porosity less than 1 %) than plasma coatings (porosity about 2.. .3 %).

Cp-Ti/TiB+TiC wear-resistance coatings produced by non-vacuum electron beam cladding of boron carbide and titanium powders are studied in the paper. The X-ray phase analysis of the composite coatings microstructure showed that titanium carbide and boride reinforcing particles are evolved during the process. The obtained data are in good agreement with results of optical and electron microscopy. Undissolved particles of the initial boron carbide powder are detected in the coatings. The microhardness test as well as wear resistance test of materials under conditions of loose abrasive particles are conducted. It is established that the precipitation of reinforcing particles improves the tribological properties of the composite coatings.

The paper shows the possibility of carburization of low-carbon steel surface layers using high-frequency currents. The mathematical modeling of carburization using high-energy heating by high-frequency currents (HEH HFC) has been carried out, the temperature fields formed during the given processing have been calculated, as well as the structural changes in the surface layers have been simulated. The features of the structure formation in the surface layers of low-carbon steel after carburizing via HEH HFC have been determined by optical and scanning microscopy, which is confirmed by the computational models. The rational mode of fusion via HEH HFC has also been determined (power density of the source q_s = (1.5 ... 4.0) • 10⁸ W m^-2, (the relative travel speed of parts V_p = 5 ... 100 mm / sec), with forming the compressive retained stresses in the surface layer (σ_RS ≈ -300 ... -400 MPa).

In this study corrosion resistance of Ti-Ta-Zr coatings fabricated on VT14 titanium alloy workpieces using a high-energy electron beam injected in the atmosphere was investigated. Estimation of corrosion resistance of surface alloyed layers was carried out by the weight-change method. Boiling solution of 65 % nitric acid in water and 5 % of sulfuric acid in water were used as the corrosive environments. Investigation of samples after corrosion tests was carried out using a Carl Zeiss EVO 50 XVP scanning electron microscope.

The effect of the modes of non-vacuum electron-beam cladding of Ta-Zr powder mixtures on the structure and properties of the layers formed on the surface of cp-titanium were studied. The mode of the electron-beam alloying of titanium with zirconium and tantalum, which ensured the formation of a defect-free layer with a high content of alloying elements was selected. Metallographic examination indicated the presence of a dendritic- and plate-type structure of cladded layers. The microhardness of the layers, formed at the optimum mode, was not changed in the cross section and was equal to 450 HV.

The paper examines the process of surface hardening of steel 45 with the help of high energy heating by high frequency currents with simultaneous shower water cooling. We theoretically justified and experimentally proved a possibility of liquid phase forming in the course of heating not on the surface, but in the depth of the surface layer.

Mechanical and tribotechnical properties of UHMWPE composites reinforced with basalt fibers and particles under dry sliding friction and abrasion were investigated. It is shown that adding of the basalt particles provides higher wear resistance under the dry sliding friction while at abrasion filling by the basalt fibers is more efficient since the wear resistance of the reinforced UHMWPE composites is by 3.7 times higher in contrast with the neat polymer. Wear mechanisms of the polymeric UHMWPE composites under various types of wear are discussed.

Sliding of metal composites against copper counterbody under severe conditions (i.e. at the contact current density higher 50 A/cm² and at high roughness of counterbody) is carried out. It is shown that the composite of composition of Cu-30% of graphite shows low wear resistance in these conditions. Higher wear resistance is inherent in the composites containing lead and bearing steel. Impregnation of these composites by industrial oil hasn't led to noticeable increase in wear resistance.

Technique preparation of a composite material based on epoxy resin DER-330 and 5 different nanopowders has been developed. The modifiers exert a positive effect on the elastic modulus, flexural strength, and dielectric permittivity of the epoxy-anhydride polymers. Weight content of nanoadditives in the matrix ranged from 0% to 4%. Dependences between mechanical properties of epoxy composites and concentration and nature of the filler were investigated in a three-point bending. Morphology of the fracture surface was studied. The complex analysis of nanofillers allowed us optimum fillers and concentrations when a significant increase of elastic and strength characteristics is achieved. It was showed that addition of silica fume nanoparticles A-380 to the matrix increases fracture stress on 30%. Composites with nanoparticles of aluminum nitride showed the best mechanical values in case of jointly investigated parameters. Growth of the elastic modulus is 12% and increase of the fracture stress is 7%. Adding alumina nanoparticles and nanofibers in the range of investigated concentration does not lead to significant changes in the mechanical characteristics of the composite

In this paper the influence of thermal shock loadings on the phase composition and microstructure of ZrO₂(Y₂O₃) and ZrO₂(MgO) ceramics was studied. It was found that thermal shock strains were no effect on phase composition of ZrO₂(Y₂O₃) ceramics. Reducing the concentration of high-temperature tetragonal t-ZrO₂ and cubic c-ZrO₂ modifications and rising the content of low-temperature monoclinic m-ZrO₂ crystal system with increasing the number of thermal shock strains were observed. The values of region coherent X-ray scattering of ZrO₂(Y₂O₃) ceramics didn't changed, while the crystallite size of ZrO₂(MgO) ceramics decreased. The formation of block structure in all studied ceramics was observed, the sizes of the blocks formed in the ZrO₂(Y₂O₃) and ZrO₂(MgO) ceramics were slightly different. The formation of the blocks in ZrO₂(Y₂O₃) ceramics occurred on the grain boundaries, while the crystallites in ZrO₂(MgO) ceramics were crushed due to phase transformation.

The paper presents the analysis of binary state diagrams based on elements VIIIA and IB of the periodic table and crystal geometry parameters of solid solutions and intermetallic compositions. The analysis shows an explicit correlation between the type of the evolution of phase diagrams classified by Lebedev depending on the nature of atomic volume deviations observed in solid solutions and intermetallic compounds from Zen law.

This article presents the mechanical properties and microstructure of titanium alloy after selective laser melting (SLM). Titanium alloys are ideal material for selective laser melting (SLM), because they are expensive and difficult to machinery using traditional technologies. The application of SLM in the biomedical area has been slow due to the stringent performance criteria and concerns related to personification and part quality. In this article we focused on the manufacture by SLM and determination of microstructure and mechanical properties of titanium alloy (Ti Grade 2 Powder) using tensile tests and X-ray diffraction. The results reveal that the alloy exhibits a pronounced the homogeneous microstructure and high mechanical strength.

The process of self-propagating high-temperature synthesis with use of a powder of sodium azide NaN₃ as a nitriding agent (the SHS-Az method) was applied to fabricate a nanocomposite powder Si₃N₄-TiN. Combustion of the initial mixtures of NaN₃ only with precursors that are halides of silicon and titanium: Na₂SiF₆, (NH₄)₂SiF₆, Na₂TiF₆, (NH₄)₂TiF₆ did not allow us to synthesize the composite powder of Si₃N₄-TiN, as the phases of silicon nitride Si₃N₄ were not formed. After water washing, the ultrafine powdered product of combustion consisted of one target phase of titanium nitride only and a large amount of impurity of side phases. Replacement of the halide salt of one of the elements (Si or Ti) by the powder of this element in the initial mixture of SHS-Az system resulted in formation of silicon nitride together with the titanium nitride and impurities. The least amount of impurities was obtained by burning the initial mixtures of xSi + y(NH₄)₂TiF₆ + zNaN₃ system. Only the initial mixture of 9Si + (NH₄)₂TiF₆ + 6NaN₃ allowed us to obtain as a result of the SHS-Az process the nanostructured composite powder of Si₃N₄-TiN without impurities.

The article presents the results of the research and development of technology and formulation of the feedstock from domestic metal powders and polymers to fabricate complexshaped components from heavy alloy of VNZh 7-3 brand (90 wt. % tungsten - 7% nickel - 3% iron) by Metal Injection Molding (MIM technology). The metal part of the feedstock is composed of powders of tungsten, nickel and iron, and the polymer part is composed of polyformaldehyde with the addition of low-density polyethylene and beeswax. The modes of mixing the components and the influence of the composition of the feedstock on the melt flow rate and the homogeneity of the feedstock were investigated. The optimal formulation of the feedstock was determined. Microstructure, density and hardness of control samples fabricated by MIM technology from the developed feedstock, correspond to, and in some respects are superior to the samples of VNZh 7-3 alloy fabricated by technology of traditional powder metallurgy.

The positive effect of the addition of MgO and TiO₂ in an amount of no more than 1 wt. % on sintering and physico-mechanical properties of alumina ceramics is established. Addition of 5% of SiO₂ to A1₂O₃ provides the mechanism of liquid phase sintering of ceramics, which leads to increase in its density and strength up to 480 MPa. In ceramic system A1₂O₃ - ZrO₂ - Y₂O₃ highest level of physical and mechanical properties of the composition had a hypereutectic composition 16.6% A1₂O₃ - 76% Z1O₂ - 7.4% Y₂O₃. In this composition two mechanisms of hardening are realized simultaneously, such as transformational hardening by t- m - ZrO₂ transition and dispersion strengthening with high-modulus particles of α- A1₂O₃.

The effect of mechanical treatment by planetary ball milling on the properties of hot pressed ZrB2 - SiC ceramics was studied. It has been shown that material densification after mechanical treatment is finished at initial stages of sintering process. Addition of SiC causes a substantial increase in density of the sample to 99% of the theoretical powder containing 20% of silicon carbide, in comparison with samples ZrB2 density not exceeding 76%. It has been shown that all defects which were accumulated during mechanical treatment anneal in hot pressure process and there are no any changes of CDD values in sintered ceramics.

The paper presents the scanning and transmission electron microscope investigations of the structure, phase composition, and morphology of heat-resisting alloy modified by thermal treatment and additionally alloyed by rhenium and lanthanum. Rhenium alloy is obtained by the directional crystallization technique. The structural investigations are carried out for three alloy states, i.e. 1) original (after the directional crystallization); 2) 1150°C annealing during 1 h and 1100°C annealing during 480 h; 3) 1150°C annealing during 1 h and 1100°C annealing during 1430 h. It is shown that fcc-based γ- and γ'-phases are primary in all states of the alloy. γ'-phase has L12 structure, while γ-phase is a disordered phase. Rhenium and lanthanum are phase-forming elements. Investigations show that high-temperature annealing modifies the structural and phase conditions of the heat-resisting alloy.

Method of azide self-propagating high-temperature synthesis (SHS-Az), using sodium azide (NaN₃) as a nitriding reagent, was used for obtaining the nanopowder of aluminum nitride (AlN) from precursor that was sodium hexafluoroaluminate (Na₃AlF₆). The product of burning the mixture of Na₃AlF₆ + 3NaN₃ after water rinsing consisted of micro - and nanoparticles of AlN (65%) and the residue of salt Na₃AlF₆ (35%). This product of SHS-Az was mixed with copper powder and pressed into a briquette of nanopowdery master alloy Cu- 4%(65%AlN+35%Na₃AlF₆), which was successfully introduced into aluminium melt at a temperature of 850°C. The salt Na3AlF6 in the product of combustion played a role of flux during introducing into the aluminum melt and was not included in the final composition of the composite alloy. The microstructure of the obtained cast composite aluminum alloy with the calculated composition of Al-1.2%Cu-0.035%AlN showed that the reinforcing particles of AlN of different sizes, including nanoparticles, were distributed mainly along the grain boundaries of the aluminum alloy.

The hydroxyapatite synthesis on a variety of substrates under various conditions was studied. It was shown that the increase in the temperature of the reaction medium increases the amount of nanocrystalline phase with an average crystallite size of 25 nm. Studies revealed that in addition to the pure hydroxyapatite, β-Ca3(PO4)2 along with calcium carbonates and carbonate-substituted hydroxyapatites were formed. A significant increase in phase crystallinity during the heating of reactants up to the reaction temperature was shown.

In this paper porous ceramics on the base of ZrO₂ nanopowders and micropowders has been developed by freeze-casting method. A zirconia/carbamide slurry was frozen in mold and dehydrated in CaCl₂ at room temperature. This simple process enabled the formation of porous ceramics with highly aligned pores as a replica of the carbamide crystals. The samples showed higher porosity of 47.9%. In addition, these materials could be used as membrane for air cleaning.

The research results of the hydrolysis processes of aluminum nitride powders received by the SVS method in dependence on humidity of the storage environment, and grain size distribution are presented in this work. Oxidation kinetics was estimated by means of X- ray Diffraction (XRD) and scanning electron microscopy (SEM). The induction period of the hydrolysis process for various powders, its dependence on powder dispersion and thickness of the oxide layer on surface of particles have been defined.

Results of research of different glass compositions for possibility of their application in metallization pastes intended for ceramics based on aluminum nitride are presented in this article. It includes research of contact angle of aluminum nitride with glasses of different compositions at different temperatures and different roughness of ceramics.

The binder of portland cement (51-59 wt.%), fly ash of thermal power stations (3644 wt.%), limestone crushing waste (4-9 wt.%) and dry hyper plasticizer (0.2 wt.%) has been created. It can be used in the building materials industry for production of high-strength concrete. The composite binder is obtained by co-milling of the components in vario-planetary mill to a specific surface area of 550-600 m²/kg. The technical result is the possibility of obtaining a composite binder with significant replacement of cement with industrial waste, cost-effective and superior to portland cement for construction and technical properties, increased activity. This allows producing concrete for walling with a compressive strength of 100 MPa, while using more than 50% of industrial waste.

The paper presents the investigations on producing spherical particles 65-110 μm in size using the energy of low temperature plasma (LTP). These particles are based on flow ash produced by the thermal power plant in Seversk, Tomsk region, Russia. The obtained spherical particles have no defects and are characterized by a smooth exterior surface. The test bench is designed to produce these particles. With due regard for plasma temperature field distribution, it is shown that the transition of fly ash particles to a state of viscous flow occurs at 20 mm distance from the plasma jet. The X-ray phase analysis is carried out for the both original state of fly ash powders and the particles obtained. This analysis shows that fly ash contains 56.23 wt.% SiO₂; 20.61 wt.% Al₂O₃ and 17.55 wt.% Fe₂O₃ phases that mostly contribute to the integral (experimental) intensity of the diffraction maximum. The LTP treatment results in a complex redistribution of the amorphous phase amount in the obtained spherical particles, including the reduction of O₂Si, phase, increase of O₂₂Al₂₀ and Fe₂O₃ phases and change in Al, O density of O₂₂Al₂₀ chemical unit cell.

The paper presents the results of modeling and calculation of highly directional optimal light intensity curve (LIC). The authors proved the effectiveness of using the calculated LIC for lighting of greenhouse plants. A method for placing fixtures with LIC in a typical greenhouse was recommended

The work presents the results of an experiment studying the effect of radiation spectral content (considering its equal intensity in terms of photosynthetically active radiation) on the growth and development of greenhouse model plants. The results demonstrate that the effective development of model subjects requires the adaptation of radiation spectral content according to the growth period and plant type, unlike the illumination level. The obtained results demonstrate the necessity of the creation of adaptive irradiation unit.