Search

The disposal of mining waste is an indispensable technological operation during the exploitation of mineral raw materials and mining activity. A new technological approach to the disposal of mining waste, which is presented in this paper, predicts that all mining waste generated during the excavation and processing of ore in open pit mines and in flotation is disposed of in integrated tailings dumps. In this way, the construction of a flotation tailings pond is eliminated, i.e., the permanent risk that may arise due to an accident situation for the environment, facilities and population located downstream of the originally planned location of the flotation tailings pond is eliminated

Awareness of environmental conservation has become a critical imperative in today's society, making waste management and pollution control central concerns for every local government. Fires on landfills and open spaces cause severe air contamination, and depending on wind direction and fire size, they can significantly affect air quality even at distances of several tens of kilometers from the source. A particular issue arises from fires on unsanitary landfills, often located near residential areas, where large amounts of improperly disposed waste accumulate without protective and control systems. These fires frequently result from incomplete combustion of waste, due to a lack of compaction and inadequate daily cover, which allows for surface oxygenation and conditions for anaerobic methanogenesis in deeper layers. Methane, a flammable and explosive greenhouse gas, contributes to ozone layer damage 21 times more than carbon dioxide. Installing gas wells (biotubes) on unsanitary landfills is crucial for preventing fires, reducing the risk of methane pocket formation, and enabling landfill monitoring. This paper presents conclusions from the remediation and fire extinguishing project at the unsanitary landfill Mislov do in Nikšić, with a capacity of 450,000 m³, where measures are being implemented to achieve measurable and sustainable results aimed at improving the existing conditions and enhancing environmental protection.

After the ecological reconstruction of the "Pljevlja" thermal power plant, ash and slag are produced as combustion by-products in amounts of 420.000 t and 70.000 t, while after desulphurization process, gypsum is obtained in the amount of 154.000 t. This paper deals with the transportation of all three materials by conveyors from the storage silo to the new material loading location within the thermal power plant.

Technological parameters also have an impact on the environment due to the exploitation of the ore deposit. Therefore, it is necessary to analyze and assess environmental risks in the approved exploitation area and take measures and conditions to prevent, reduce and eliminate harmful impacts on the environment and human health. The aim of the paper is to emphasize that it is important to manage the environment, that measures should be determined and taken to eliminate, prevent and reduce environmental impacts in order to meet the conditions for further uninterrupted operation of the mine without violating legal provisions regarding environmental protection.

This paper will cover the Preliminary Design of the by-products transport system after the Ecological reconstruction of the thermal power plant Pljevlja. The 4.5 km belt conveyor long route enters the tunnel at Borovica Lake. Tunnel position is in relation to the route, the cross-section selection, calculation of structural elements and fitting into the ambient unit around the lake are described.

The aim of this paper is to present the principle of testing electrical insulation mats and the results of the tests as well as observed irregularities in their operation in transformer stations 35/10 kV (TS 35/10) in Serbia. In accordance with the progress of technology, more and more automation and computers are being introduced in the management of the operation of TS, and the basic concepts of protection against contact voltage and step voltage of the staff who work and stay in these facilities are neglected. The fact is that these TS are facilities where people are not constantly present, but they still spend a certain amount of time in them and are exposed to various dangers. Electrical insulation mats were tested in several TS and the results were devastating. In addition to non-compliance with work procedures, these facilities often leak, various rodents are present, and unsanitary conditions are at an enviable level. The main problem is that the electrical insulating mats are not adequate for their purpose, they are not properly installed, the lack of proper inspection supervision, as well as the shortcomings in the legal regulations that define this area

The driver of modern world industry is electricity. Production, distribution and use of electricity affect the functioning of modern industrial plants, the process of communication in the modern world, as well as numerous other types of services that are necessary for people's lives. The technological process of coal-based electricity production contributes to the increased emission of gases that have a large negative impact on the environment. Carbon dioxide (CO2 ), sulfur dioxide (SO2 ), nitrogen oxides (NOx ), carbon monoxide (CO) and solid PM particles are the main constituents of polluting gases from thermal power plants. All the mentioned compounds have harmful effects on the environment, and in the long term they also affect climate change (greenhouse effect). Due to the aforementioned problems, it is important to apply the principles of corporate social responsibility to companies in the energy sector. The aim of the paper is to evaluate the impact of the organizational structure of the company on the development of the system of corporate social responsibility in companies from the energy sector. The research results confirmed the positive impact of the organizational structure on socially responsible business practices

This paper describes an example of applying the machine learning to predict the SO2 blower vibrations. The SVR (Support Vector Regression) algorithm was used to form the model. The paper includes an overview of machine learning and mathematical fundamentals of the SVM model. Based on a large amount of data, obtained from the monitoring system, a mathematical model was constructed. After testing, the measures of model accuracy such as the MSE (Mean Squared Error) and R2 were provided.

In addition to traffic, the main source of nitrogen dioxide is also industrial plants where combustion takes place at high temperatures, such as heating plants and smelters. Nitrogen oxides from traffic are the dominant component of air pollution in large cities and represent an important source of exposure and health risk for people, especially those who move along busy roads. In Bor, real-time nitrogen dioxide concentrations have been measured since 2010 at the measuring point "Institute IRM Bor" near Mining and Metallurgy Institute Bor. This paper presents an analysis of the results of measuring nitrogen dioxide concentrations in Bor in the periods 2010-2013 and 2019-2023. Based on the analysis of nitrogen dioxide measurement results, it was established that in both periods there are seasonal changes (heating/non-heating season) in nitrogen dioxide concentrations. Nitrogen dioxide concentrations were on average 17% higher in the heating season than in the non-heating season. Also, in the period 2019-2023 the average concentration of nitrogen dioxide was 28.6 µg/m3 , which is about 18% more compared to the period 2010-2013 in which the average concentration of nitrogen dioxide was 24.3 µg/m3 . In the observed periods, there was no exceedance of the limit value for the average annual concentration of nitrogen dioxide of 40 µg/m3 . However, several days were recorded with an average daily concentration of nitrogen dioxide above the daily limit value of 85 µg/m3 .

The air quality in the city of Bor in 2023 is analysed in this paper. In the period from May 1, 2022 until April 1, 2023 the copper smelter in Bor was not working due to reconstruction and capacity increase. The analyses show that in 2023, no exceeding of the daily limit value for SO2 , PM10, and soot concentrations was detected at any measuring point. During the reconstruction of the copper smelter, correlation coefficients (Pearson) at measurement point "Jugopetrol" between PM10 and the chemical elements Cd and As were moderate (0.6>r>0.4), while in the period before and after the reconstruction of the smelter, they were strong (0.8>r>0.6), and very strong (r>0.8). The results presented in the paper indicate that despite the reconstruction of the copper smelter, the problem of emission of high concentrations of carcinogenic elements in PM10 from the copper smelter is still present. It is necessary to urgently implement additional measures to reduce these emissions to the values provided by law.

Accredited Laboratory for Materials Testing within the Mining and Metallurgy Institute (MMI) Bor has a primary role in testing steel ropes for export facilities in mining. Reliable and valid test results require the possession of correct and high-quality equipment, as well as the competence of the operators for this type of test. Testing of the correctness and reliability of the equipment is carried out using our own reference material of known characteristics, confirmed in other laboratories. The paper presents the results of testing samples of own reference material on a simple twisting test device. The results obtained using the X-control chart showed that the method of twisting the samples is under control, i.e., the acceptability of the results obtained using the tested method was confirmed, which means that the correctness of the device is at the required level.

The aim of the paper is to present the method of implementing and using relay protection with a special emphasis on microprocessor relay protection in Electric power distribution Kruševac, and based on the presented concrete examples of settings and operation of protective devices that were collected from practice and paper in the field. The software packages Test Universe were used in the paper for testing protection in TS "Kruševac 1" on the 1158B transmission line in the direction of "Kruševac 4" on the 110 kV network, as wel as Test Universe software package for testing protection in TS "Kruševac 1" on the 1158B transmission line in the direction of "Kruševac 4" on the 110 kV network. During the test, movement of the current and voltage values, disconnection times, as well as characteristics that show operation of each protection were monitored on the computer. The paper in the practical part shows the detailed connection of the equipment for testing the functions of the microprocessor protection relay of the 110 kV transmission line. For a specific transmission line, parameters, images of devices and complete test equipment, as well as official test lists with actual tripping values are provided. Advantage of modern microprocessor relays reflects in the fact that all functions are combined in one compact box that communicate with each other using special protocols and thus facilitate the work of users.

The analysis and proposed optimization technique of asynchronous electric drives of production machines with a cyclic impact load, under the condition of minimum energy consumption, was presented in this paper. The mean values of the electric motor torque in the working range of a slider, were adopted in calculation. The derived formulae can be used to calculate the optimal parameters of the electric motor drive.

This paper presents the results of the air quality measurements in the agglomeration of Bor in the period June-December 2022, in which the Copper Smelter in Bor was not working due to the works on reconstruction and increasing the capacity for copper concentrate processing. Based on an analysis of the existing measuring points and concentrations of pollutants, measured in the local and national air quality monitoring network in the territory of the Bor agglomeration, as well as the possible impact of the new mining and metallurgical facilities in the company Serbia ZiJin Copper Bor, the additional locations, where the measurements were performed, were selected. The air quality measurement results show that there was no exceedance of the hourly and daily limit values for gaseous pollutants, nor were there an exceedance of the limit value for the mean daily concentration of lead in the suspended particles of the PM10 fraction, as well as the target values for the concentrations of cadmium and nickel in PM10. The arsenic concentration in PM10 at the measuring point of PU Bor was above the target annual value for 3 days. The maximum measured mean daily value of arsenic concentration in PM10 at this measuring point was 11.3 ng/m3 . Based on a complete insight into the results of air quality measurements in the Bor agglomeration in 2022, it can be concluded that the dominant share of concentration of SO2 , CO, as well as the concentration of arsenic, cadmium, and lead in PM10, originates from the gaseous pollutant emissions from the Copper Smelter Bor in the period when it operates. It was established that at the measuring point MMI Bor, the nitrogen oxide emissions from traffic mostly affect the level of nitrogen oxides in the air. Also, the measurement results indicate that the operation of the Smelter in 2022 did not significantly contribute to the concentration increase of suspended PM10 particles in the agglomeration of Bor, and that during the period of operation of the Copper Smelter in 2022, no copper concentrates with increased nickel content were processed.

The environmental protection and renewable energy sources are the priority of all investments around the world. The environmental monitoring systems are equipped with various sensors, devices, networks and software to collect, process, monitor and display data on the environmental parameters. In that sense, this paper discusses the automation of river water quality monitoring in the area of the "Čukaru Peki" copper mine in Serbia. Until now, the water quality in the area is being monitored by taking and analyzing the water samples in the competent laboratory. The automation would improve the quality of monitoring multiple times. At the same time, the significantly cheaper ("low cost") devices can be used. These devices are cheaper and their quality is for a specific application completely at the level of those offered on the market as commercial pnes. The problem is briefly considered in terms of costs and benefits.

The subjective experience of the environment where people live defines the comfort of that environment. The elements of environmental comfort are the air quality, thermal comfort, visual comfort, and sound comfort. The air quality in the room where people stay can significantly affect their concentration, i.e., the ability to work and study. The concentration of CO 2 in the room is used as an indicator of ventilation, that is, as an indicator of the air quality in the observed room. The thermal comfort defines a state of satisfaction with the thermal environment. The thermal comfort is achieved when the environment properties are such that they ensure the release of BAKAR 48 (2023) 1 COPPER body heat within the comfortable limits. This paper presents a part of the air quality and thermal comfort measurement results in the selected office in the Mining and Metallurgy Institute Bor from 2020 to 2022. Based on the analysis of measurement results, it was determined that the air quality in the selected office was satisfactory on an average of more than 90% of the working time, and the thermal comfort on an average of about 60% of the working time.

In the modern business of accredited testing laboratories according to the requirements of the SRPS ISO/IEC 17025 standard - General requirements for the competence of testing laboratories and calibration laboratories, the most important thing is the correctness of the testing equipment. The work procedure of the Laboratory for Material Testing in the Mining and Metallurgy Institute Bor requires checking the correctness of equipment twice a year in order to obtain the reliable and valid test results. This paper presents the procedure of intermediate verification the correctness of a device for testing the metal materials by tensioning, using a X-control card. The Xcontrol card is an auxiliary tool for collecting, processing, analyzing and displaying data in order to ensure the quality of products and processes. It belongs to the Statistical process control - SPC. The control chart that is created as a result of the statistical processing of the obtained data of tensile strength of wire on a tensile testing device shows the measure of quality the device correctness in the laboratory. The main goal of the X-control card is a very fast detection of errors during the work process of the Laboratory for Material Testing in the Mining and Metallurgy Institute Bor, i.e., checking the correctness of device.

Geotechnical and hydrogeological investigations were carried out at the location on the sector 6 of the "Valja Fundata" flotation tailing dump in Majdanpek. The goal of investigations was to define the geotechnical and hydrogeological structure of this part of the tailings dump, as a basis for determining the optimal conditions for overhanging and rehabilitation of the terrain, planned for the landfill expansion. The appropriate geotechnical and hydrogeological terrain models, which will be used as a starting point for further construction and mining design, were developed applying the multidisciplinary geological investigation models.

The soil properties are studied in mechanics, that is, the important properties according to which the soil can be classified. Based on mechanics, the information is being obtained on how the tested soil can be used. For example: which soil is favorable for the construction of various types of structures, which soil is favorable for the construction of embankments, etc. There are several ways to determine the elements of internal soil resistance, cohesion and angle of internal friction, using the laboratory tests, among which the most famous are the direct shear test, triaxial compression test and uniaxial compressive strength test. This paper will describe the "CU" triaxial test results.

Metal foam is a cellular structure composed of solid metal with a high proportion of gas-filled pores. The main division of metal foams is into foams with the open and closed cells, on which the area of their application mostly depends. The open-cell foams are suitable for the wastewater treatment process, as they allow the water flow through the pores trapping the toxic substances in the pores. This study provides a summary of literature data on morphology and application the copper metal foams in the wastewater treatment.

Validation of analytical methods ensures reliability and accuracy of analytical data. Accredited laboratories in accordance with the international standard ISO/IEC 17025, that is the Serbian standard SRPS ISO/IEC 17025, must fulfill and document the selection, validation, or verification of the analytical method. In the validation and verification process, it is mandatory to assess: limit of detection (LoD), limit of quantification (LoQ), linearity and measurement uncertainty.

Waste oils are dangerous waste, because they can contain high concentrations of metals, hydrocarbons, PAHs, chlorinated compounds, phenols and other substances that come from additives and are created as a result of the operation of different types of engines. This type of waste can cause major problems and contamination of the environment, both soil and water, if they are not treated in the right way and they are wasted. Their identification and further characterization as hazardous waste according to the waste regulations of the Republic of Serbia - Rulebook on categories, testing and classification of waste ("Official Gazette of the RS" no. 56/2010, 93/2019, 39/2021) and Rulebook on the conditions, method and procedure of waste oil management ("Official Gazette of the RS", no. 71/2010). In this paper, GC/MS analysis of different types of waste oils (engine, hydraulic, machine, mineral non-chlorinated oil, synthetic oil) was performed. The obtained chromatograms were compared with the chromatogram of the standard (Dr. Ehrenstorfer) which contains the same ratio of diesel oil and mineral oil without additives. In this way, the analysis of the so-called "fingerprint" and characterization for different types of waste oils was performed, which is very important for comparison with analysis of oil in natural samples (water, soil) in order to determine the original source of pollution.

The paper presents the application of computer systems for monitoring in the fields of electrotehnics, mechanical engineering, and construction. It outlines the basic principles of thermal radiation from objects and describes the operation and structure of a thermal imaging camera, providing practical examples in the mentioned fields. The document showcases examples of in-formation systems for monitoring, along with thermograms obtained through this method.

On the basis of data obtained by the exploratory drilling, the researched copper ore deposit belongs to a group of deposits related to intermediate volcanic - intrusive magmatic complexes. It is a compact ore body with the shape of an inclined cylinder and is composed of copper minerals together with the chloritized and kaolinized andesite. There is also an impact of technological parameters on the environment due to the exploitation of the ore deposit. The aim of this paper is to emphasize that it is important to manage the environment in surface exploitation of ore deposits.

The purpose of this analysis is to show whether mining activities have an impact on the grondwater and drinking water quality. Water samples were analyzed in three unfavorable climatic periods during the winter of 2018-2019. The obtained results show that the heavy metal concentrations in water samples do not have values higher than the allowable according to the current statutory regulations. Also, the heavy metal concentration did not change with changes in climate parameters. However, a higher concentration of molybdenum than statutory by the law was found in the period of snow melting. This has shown that in extremely unfavorable climatic conditions, the karst groundwater can contain certain metals that can origin either from the surrounding field or as a result of mining activities, considering that there are two open pits s in the immediate vicinity of the "Surdup" source.

In the process of financial analysis, an inevitable place belongs to the quantitative analytical methods. During the economic development, the analytical processes became more and more important, so that it conditioned their development. Applying various methods of analysis the financial statements such as the horizontal, vertical or ratio analysis, the operational management obtained the necessary information, but a new corpus of methods was constantly invented and developed for the strategic decision-making. In this context, the Data Mining methods also find their place. The subject of this paper is the application of one of the accepted methods of the Data Mining in the financial analysis on an example of a metal industry company, the so-called Group Method of Data Handling

Inductively coupled plasma mass spectrometry (ICP-MS) has been an indispensable technique in the analysis of geological samples in the last few decades. This technique can determine a large number of trace elements, such as the precious metals and rare earth elements. However, the technique is limited by the spectral and non-spectral interferences, which can affect the results of analysis. The aim of this study was to reduce the non-spectral interferences by the method of sample dilution (1000 - 10000). A sample containing gold-bearing minerals was subjected to a digestion in aqua regia, and determination was performed on a NexION 1000 PerkinElmer ICP-MS instrument. The results showed that the differences in gold and silver concentrations in the standard and He modes were insignificant at a dilution of 10000 indicating that the matrix effect was reduced applying a higher dilution. The results of XRD analysis have showed that the sulphide minerals pyrite (FeS2 ) and covellite (CuS) were very abundant in the tested samples, so the digestion of these samples with aqua regia has yielded the solutions containing iron and copper as the most abundant components of the matrix.

The competent and experienced staff is one of the criteria for assessment the technical competence of the laboratory. This paper presents the AHP analysis of competent and experienced laboratory accreditation staff. The following sub-criteria were analyzed: training SRPS ISO 17025:2017, training ISO 9001, training staff to work on a particular machine using a valid method, responsibility, impartiality, confidentiality, authority and interpersonal cooperation of the laboratory staff. The criterion for competent and experienced staff should meet all the requirements for the technical equipment of the laboratory to submit an application for accreditation.

After the migration of Serbs in 1690 and 1735, the exploitation of mines in the area of present-day Serbia ceased, and after a standstill of nearly 200 years, the mining and metallurgical activities in Serbia were activated in the second quarter of the 20th century. The first concessions were bought by England in 1926, then the mines in Stari Trg (1927), Kišnica (1927), Ajvalija (1930), Novo Brdo (1933) were activated, and the Flotation (1930) and Smelter with Lead Refinery began to operate (1939) in Zvečan. In Kosovska Mitrovica, the chemical industry began operating in 1961, the Zinc Metallurgy and Lead Battery Factory in 1967, and all production facilities were expanded and modernized several times. The most intensive production and investment period of the "Trepča" Combine was in the period 1965-1985, when "Trepča" was a well-known producer of lead, zinc, silver, gold, cadmium, bismuth and products made of these metals. After 1990, the production declined for several reasons and, in 1999, the international army stopped production in "Trepča". In the past twenty years, the production has not been completely renewed nor the status of the "Trepča" Combine has not been regulated.

The analysis of the formation process of the cast structure of carbon steel grade ОС (ДСТУ ГОСТ 4728:2014) after the completion of its crystallization with a change in a wide range of metal cooling rate during solidification of a continuously cast billet (ССB) with a diameter of 450 mm has been carried out. The effect of the cooling rate during the solidification of ССB Ø 450 mm on the parameters of the chemical heterogeneity of the distribution of silicon and manganese in the microstructure of carbon steel has been shown. It has been determined that the effect of the metal cooling rate during the solidification of the investigated CCB on the size of dendritic crystals is described by the inversely proportional relationship: у = 423.75 х-0,161. With a change in the cooling rate of the metal during solidification from 106 до 1 °C/min, the size of the dendrites in the direction from the surface to the central layers of the CCB Ø 450 mm increased by ~ 8 times, and the density of the dendritic structure of carbon steel ОС decreases by 65 times. In this case, the nature of its dependence on the intensity of heat removal is the opposite nature of the change in the size of dendrites. It has been established that by varying the cooling rate in the range 1 – 106 °C/min, one can achieve a significant change in the average size and density of dendritic crystals while maintaining the constancy of the volume fraction of segregation areas of silicon and manganese ~ 24% in carbon steel (0.42 – 0.50 % wt. C). It has been determined that in the entire investigated range of cooling rates 1 – 106 °C/min, the coefficients of dendritic segregation КдI and КдII of silicon and manganese change insignificantly and amount to 1.8-1.9 and 1.5 for КдI and КдII, respectively. In this case, the values of the coefficients КдI and КдII for both elements are practically constant in both pearlite and ferrite. It has been proven that both silicon and manganese have high diffusion mobility only at sufficiently high temperatures, when steel is in a solid-liquid state. Based on the results of X-ray microanalysis, it has been established that the heterogeneity of the distribution of chemical elements, which is formed as a result of dendritic segregation of silicon and manganese, is the primary and constant component of the microstructure of carbon steel.

The dependences of diffusion coefficients in metals with different crystal lattice (b.c.c., f.c.c., h.c.p., b.c.t.), subjected to pulse effects by different types of processing in a wide range of strain rates (10-2 - 106 s-1) without heating and at T < 0,5 Tpl. studied by m ethods based on the use of radioactive indicators 55Fe, 95Nb, 60Co, 65Zn, 63Ni, 26Al, 44Ti (layer-by-layer radiometric analysis of residual integral activity, macro- and microautoradiography). Used such types of processing as ultrasonic shock treatment, diffusion welding, shock load, magnetic pulse processing, etc. On the same materials subjected to the same types of processing, mechanical characteristics (impact strength, microhardness, tensile strength, etc.) were determined. In addition, literature data related to the determination of some mechanical characteristics in the deformation of metals at different speeds were used. It turned out that with increasing the rate of plastic deformation there is not only an increase in the mobility of atoms, but also a decrease in differences in the values of the diffusion coefficients of intrinsic atoms and other diffusers in different metals. Despite the large difference in melting temperatures, in particular zinc and niobium, their self-diffusion coefficients in the migration of atoms without heating at a rate of 106 s-1 differ only 1.5 times, while at 1 s-1 the difference in the mobility of atoms is 4 orders of magnitude. It is shown that the velocity dependences of diffusion and mechanical characteristics can be rectilinear, have extremum or inflection, but they will be approximately the same for diffusion coefficients and parameters that characterize the mechanical properties of metals under impulse loads. Establishing the type of velocity dependences for diffusion and mechanical characteristics makes it possible to determine intermediate and extrapolated values for both characteristics, as well as on the schedule of one dependence to predict the shape of the other with a certain accuracy.

Today, in the world, it is widely used in the production of aerospace equipment, sea vessels, railway transport and cars have high-strength aluminum alloys Al-Zn-Mg-Cu (for example, B95) and alloys of medium Al-Mg (AMg5), Al-Si-Mg ( AD35) and increased strength Al-Cu-Mg (D16). An in-depth study of individual factors that directly affect the structure of the work piece can be crucial for improving product quality during further thermomechanical processing. The article defines data on the grain size of the primary phase of aluminum alloys depending on the cooling rate of castings of various aluminum alloys (AD35, B95, D16, AMg5). It is shown that an increase in the cooling rate from 2-8 ° C / s to almost 1000 ° C / s leads to a decrease in the grain size of the фазы-phase from 200 μm to 10-40 μm. As a result of the experiments carried out in the work, the intervals of hardening of the investigated aluminum alloys were determined. It is shown that aluminum alloys containing copper in the chemical composition (≥1%) have a significantly wider crystallization range, in particular, B95 (1600C) and D16 ( 1320C). The samples of strip used in this work from high-strength aluminum alloys obtained by roll casting, to expand the range of investigated cooling rates, have a homogeneous structure with a uniform distribution of phase components, which ensures high functional properties of rolled products from high-strength, heat-strengthened alloys of the Al-Cu and AL-Zn systems. The obtained data of the research results can be recommended for use in the development of the domestic technology of roll casting of high-strength aluminum alloys.

An integrated approach to the generalization and analysis of scientific and technical literature in the direction of improving the technological processes of spraying metal melts used a comprehensive approach The processing and analysis of experimental data for the determination of argon at different stages of heat-resistant alloy production were performed. Micro structural analysis of nickel-based heat-resistant alloys obtained by gas and centrifugal spraying was performed. A significant increase in the mass fraction of argon in the melt is shown when held in a furnace before gas or centrifugal spraying, the absence of capture of inert gas by sprayed liquid particles during centrifugal spraying is shown, unlike the process of gas spraying, it is shown. The results of the study indicate the absence of "dissolution" of Ar or a mixture of Ar-He in the liquid or solid state at argon levels up to 1 • 10-4% of the mass. It is established that centrifugal spraying of metal melts allows obtaining compact powders with small particle size distribution at relatively low energy consumption. It is also noted that argon is captured by the metal only in the process of moving on the disk, and not due to the weak dynamic gas interaction directly on the melt droplets. Hence, its amount in the metal increases after the argon’s injection into the furnace chamber and at the subsequent centrifugal spraying does not change, in comparison with gas spraying. A technological possibility has been found to significantly reduce the amount of gas pores and the mass fraction of inert gas in nickel-based heat-resistant alloys. Nickel-based heat-resistant alloys obtained by the method of gas and centrifugal spraying make it possible to improve the quality of products for the aviation industry, their reliability when operating in extreme conditions.

The paper presents the results of the study of the influence of chemical composition, temperature, stress and operating time on the creep and durability of structural steels. It is shown that the efficiency of structural steels in conditions of elevated temperatures and loads depends on the chemical composition, stress level, operating time and temperature. The influence of alloying elements is associated with the inhibition of the process of weakening of heat-resistant steels due to the reduction of their diffusion mobility and intensity of redistribution between the ferrite and secondary phases, their coagulation and reduction of structural defects. Mathematical models of relative elongation and fracture time in the process of creep from operating conditions and degree of alloying of steel are constructed. It is established that the efficiency of heat-resistant structural steels depends on 61 - 64% of the degree of alloying, 18 - 21% - the value of external stress, 7 - 18% - temperature and 11% of operating time. It is shown that the coagulation of carbides and nitrides in steels doped with nitrogen and vanadium is slower than carbides in steels doped with molybdenum, which more effectively shifts the softening process of heat-resistant steel in the region of higher temperatures and time.

In modern nickel nickel-based high-temperature strength alloys of the ZhS32 type with a directional and single-crystal structure on surfaces that were previously subjected to mechanical treatment, with the subsequent isothermal exposure in the vicinity of the homogenization temperature lasting more than 15 minutes a subsurface recrystallized layer up to 40-65 μm deep is formed such us a chain of grains. The formation of this layer is a side effect that restrained the industrial application of vacuum heat treatment to restore local operational degradation ("raft"-structure) on the overheated inlet edges of non-bandage shelved gas-cooled high-pressure turbine blades of some modern aircraft turbine engines. Given the technical complexity of reliable removal of this recrystallized layer from the tract surface of thin-walled gas-cooled blades, it is important to develop technological measures to translate grain boundaries in unremoved residues of recrystallized near-surface layer into a safer structural state. The regularities of recrystallized layer formation in the process of 3-stage reductive vacuum treatment has been investigated by the methods of raster electron microscopy and X-ray structural (EDX) microanalysis at magnification up to × 2000 on fragments of TVT blades with ZhS26-VI alloy (directional structure) and ZhS32-VI alloy (monocrystalline structure). It has been established that the recrystallized layer formed in the process of aging 1.25-1.5 hours at the temperature of alloy homogenization, is a chain of grain with a tightly packed γ׳-phase with layers at their boundaries, which consist of the non-reinforcing γ׳-phase up to 1-3 μm wide with the carbide phases presence. It has been shown that the rational choice of the temperature of high-temperature aging is an effective technological control of the grain boundaries structural state in a near-surface recrystallized layer of the considered high-temperature strength alloys. Assigning a temperature of 1050°C for isothermal exposure after homogenization heat treatment for ZhS26 and ZhS32 alloys allows to reduce the grain boundaries width in the recrystallized layer to 1-2 μm, keep them intermittent and avoid systematic release of carbide particles at the grain boundaries. On the basis of established in the Paton welding institute of regularities of formation and control of the structure of the near-surface recrystallized layer developed technological recommendations for optimizing the vacuum heat treatment modes to restore the structure of non-bandage shelved gas-cooled high-pressure turbine blades with type ZhS32 high-temperature strength alloys. This technology has passed experimental and practical testing during the next maintenance cycle of flight operation on one of the modern turbojet double-circuit gas turbine engines with afterburner combustion chamber.

A method of deformation-heat treatment is considered for Al-Si alloy with 4.5 % silicon, which consists in a series of small hot deformations with intermediate annealing. The proposed method allows one to achieve grinding and spheroidization of silicon inclusions, which in the cast state have the form of lamellar excreta at the grain boundaries and significantly reduce the plasticity of the material. Spheroidization, grinding and mixing of inclusions that are achieved during this deformation-heat treatment lead to significantly increase the ductility of the alloy without loss of hardness. The processes of structure change during the deformation of aluminum alloys with low Si content are insufficiently studied. In particular, of interest was the possibility of increasing the ductility of such materials by grinding and mixing silicon inclusions during hot deformation. In this case, to prevent a decrease in ductility due appearance of microconcentrators of stress in the form of acute angles of the crushed silicon inclusions, the deformation was carried out as a series of stages with intermediate annealing. In addition, it was assumed that the cyclic change of temperature in this mode will contribute to the spheroidization of fragments of crushed silicon inclusions by changing the solubility of silicon in solid solution from temperature. It is shown that the proposed mode of deformation-heat treatment of these alloys of the Al-Si system allows to significantly increase their ductility – the critical degree of deposition (deposition before cracking) from 67.8 % in the cast state to – 92.1 %. The hardness of the material can be increased by hardening under cold plastic deformation. In this case, since the material after deformation-heat treatment is more plastic, it has greater reserves for hardening in this way. It is shown that owing to hard plastic deformation, the hardness of the material of samples with 4.5 % Si, which has undergone deformation-heat treatment, can increase to values of 95 ± 17 HV, which is significantly higher than in the cast state. At the same time, the hardness (and, probably, strength) of a similar cast material can also be increased due to hardening, but to lower values – 67 ± 12 HV.

A conceptually new technology for the application of aluminum coatings on 18G2C steel by the electrolytically deposited NaF-NaCl - AlF3 ionic melt method has been developed. To solve the tasks set in the work, a set of experimental and computational research methods was used: metallographic analysis, energy dispersion microanalysis, mechanical tests, and calculation of the oxidation rate of samples. The mechanical characteristics of the samples of reinforcing steel were determined on a rupture machine FP-100 at an active capture rate of 2.5 mm / min. The relationship between the rates of electrochemical oxidation of the aluminide coating, its mechanical properties, with the distribution of aluminum in the depth of the samples and its phase composition have been determined. The increase of mechanical characteristics of samples from 18G2S steel with an aluminum covering in comparison with usual reinforcing steel is shown. The sequence of structural-phase changes of metal in the process of aluminide coating is determined and its influence on mechanical and corrosion resistance is determined. Experimental evaluation of the rate of oxidation of 18G2C steel samples with aluminum coating under the conditions of sulfuric acid electrolyte at an electric current of 11 to 18 A has been conducted. The developed technology of electrolytic deposition of aluminum has scientific and practical interest for the construction industry. The developed coating makes it possible to increase the mechanical properties of steel by almost 12% and to increase the corrosion resistance.

For creation of the high-tech equipment that is used in energy, heavy engineering, chemistry and transport, the unique large-sized steel products are required. In the manufacture of such products, large forging ingots in the mass to 600 tons are used. However, an increase in the mass of the ingots leads to the formation of chemical and physical heterogeneity, enlargement and unfavorable distribution of non-metallic inclusions, of the development of segregation defects in them, which reduce the strength and exploitation characteristics of the metal. In this connection, the quality forgings and finished parts are not always meet the producing demands and the loss of metal, in the form of technological waste and rejects are reaching significant values. It is known that eccentric zonal segregation, especially it’s the most dangerous variety - cords, significantly reduce the quality and properties of products from large steel ingots. In connection with the continuous expansion of the production of large ingots, the problem of creating optimal technologies for their formation, which reduce or exclude the possibility of the formation of chemical heterogeneity and cords in steel during crystallization, it is currently important and relevant. In this paper it are presented the results of studies of the structure, gas distribution, physical and chemical heterogeneities in the cross section and height of an ingot in the mass of 140 tons, which was casted in vacuum from steel 25KHN3MFA. It is shown that depending on the temperature and time conditions of ingot hardening, among which the crystallization interval (due to the chemical composition of steels), cooling intensity in different volumes in height and cross section of ingot, temperature gradient before the crystallization front, solubility of alloying elements and gas content in the melt, etc. Based on this, when developing technology for large ingots to ensure their quality, optimal structure and properties should take into account not only their dimensions, but also the combination of these thermokinetic parameters on the crystallization process, dendritic structure formation, manifestations of liquation in different ingot volumes.

In this work the kinetics of the hydrogen reduction process of nickel oxide nanopowder in non-isothermal conditions were studied. NiO nanopowder was prepared in advance by thermal decomposition at 300°C of nickel hydroxide Ni(OH)2. Ni(OH)2 nanopowder was prepared by chemical deposition from aqueous solutions of nickel nitrate Ni(NO3)2 (10 wt. %) and alkali NaOH (10 wt. %) at room temperature, pH=9, under the condition of continuous stirring. The hydrogen reduction process of NiO nanopowder in non-isothermal conditions was carried out in the linear heating mode at a rate of 5°C/min in the temperature range 25–400°C. The study of the crystal structure and composition of the powder samples was performed by X-ray phase analysis. The specific surface area S of the powders was measured using BET method by low-temperature nitrogen adsorption. The average particle size D of powder samples was determined via the measured S value. The size and shape of the particles were investigated by scanning electron microscopic method. The calculation of kinetic parameters of the reduction process of nickel oxide in non-isothermal conditions was carried out by the differential-difference method using the data of thermogravimetric analysis and the equation for non-isothermal kinetics. It was revealed that the hydrogen reduction process of NiO nanopowder in non-isothermal conditions occurs in the temperature range 240–300°С with a maximum specific rate of 13,045•10-8 kg/s recorded at 280°С. The activation energy for the reduction process of NiO nanopowder was estimated at ~59 kJ/mol, which confirms the kinetic mode of limiting the process. It is shown that an increase in temperature to 280 °С can effectively increase the rate of the overall hydrogen reduction process of NiO nanopowder while guaranteeing the quality of the reduction product. The obtained Ni nanoparticles mainly have a rounded shape, their size ranges from 40–80 nm.

The study of unfavorable titanium alloy powders of VT20 grades was carried out and the methods of computer analysis were applied to determine the parameters of their optimal packaging. Metallographic studies were performed on a scanning electron microscope EVO-40XVP, and elemental analysis was performed using an energy dispersion spectrometer OXFORD INCA Energy 350. Determination of particle size distribution of powders was performed using image analysis software ImageJ. The surface morphology of non-spherical particles of VT20 alloy powder was studied for three different fractions: 100 ... 160 μm, 160 ... 200 μm and 200 ... 250 μm. It is shown that the powder particles are characterized by a nonspherical shape and a small difference in size. There is a tendency according to which when the particle size of the powder of the investigated alloy decreases, their shape approaches spherical. According to the results of particle size analysis, it was found that the usual sieve analysis does not allow to fully assess the distribution of powder by fractions. It was found that for the fraction 200 ... 250 μm the dominant particles are with an average diameter of 226 μm, for the fraction 160 ... 200 μm - 177 μm and for the fraction 100 ... 160 μm - 114 μm, respectively. Thus, for the fraction of titanium powder of the BT20 brand 200 ... 250 the polydispersity is 6.4%, for the fraction 160 ... 200 - 8.3%, and for the fraction 100 ... 160 - 9.1%. It is established that the fluidity of titanium alloy powders of the BT20 brand is: for the fraction 200 ... 250 μm - 62.35 s, for the fraction 160 ... 200 μm - 65.44 s, and for the fraction 100 ... 160 - 68, 73 s. That is, the highest value of fluidity is characterized by the powder with the largest particle size. Simulation of the pre-defined volume filling was performed using the "Spheres test" program. The average radii of particles of VT20 titanium alloy powder particles and the probability of the sizes of each of fractions of powder which is necessary at filling of the set volume was calculatedthe possibility of their precipitation have been established. Based on the obtained results, the packing density of VT20 titanium alloy powders was calculated depending on their fractional composition. It is confirmed that as the particle size of the powder decreases, their packing density increases. The surface morphology of non-spherical particles of VT20 alloy powder of different fractional composition and their particle size characteristics were studied. It is shown that with decreasing fractional composition of powder fractions, their homogeneity and bulk density increase. It was found that finer fractions are characterized by poorer fluidity. The simulation results determine the optimal fractional composition of the powder to fill the pre-specified volume. It is shown that as the size of the test particles decreases, their packing density increases.

The results of the study of the effect of nanoparticles in the shell of iron oxide Fe2O3, which when injected into the melt and heated up to melt temperature is converted into oxide Fe3O4, on the microstructure of hardened and tempered steel 25GSL and its properties. It is shown that in modified steel martensite crystals thickness is reduced compared to the original steel in average 1.9 times after the quenching, tempered martensite crystal length after tempering hardened steel at 200oC - 3 times, the plate cementite length in troostite after tempering hardened steel at 450 оС – 1,4 times, the carbide length of after tempering of steel at 550 оС – 1,6 times. It has been found that modification of iron nanoparticles in a shell of Fe3O4 oxide leads to dispersion of the subgrain structure (regions of coherent scattering) and to the decrease of the crystal lattice parameters of solid solutions. The mechanism of nanoparticle influence on the reduction of the crystal lattice parameters of solid solutions, which is to accelerate the diffusion of interstitial atoms of the elements into the zones of high stress on the nanoparticles surface, is proposed. It is determined that the optimal improvement mode of the modified steel is quenching at 900 °C and tempering at 550 °C. The yield, tensile strengths and toughness of the modified steel are 894 MPa, 993 MPa and 92 J/mm2, respectively, on 62, 41 and 14% higher than the original steel. The injection of iron nanoparticles in a refractory shell into the steel melt before crystallization predetermines the effective modification and enhancement of mechanical properties.

The results of researches on steel 4H4N5M4F2 modes thermo-deformation processing optimization are given. It is established that incomplete annealing (750 °С ± 20 °С in comparison with full annealing 860 °С) in cast and forged condition promotes to improve the machining of blanks for the manufacture of matrices. It is shown that the use of incomplete annealing, namely partial recrystallization promotes the formation of spheroidized rather than lamellar carbide phase, which leads to a decrease in the characteristics: strength threshold, yield strength, hardness 900 MPa, 800 MPa, 32 33 HRC in the cast state and 1200 MPa, 1050 MPa, 38 39 HRC in forged condition, respectively. This increases the fracture toughness: 180 J/cm2 in the cast state and 130 J/cm2 in the forged state. The optimized mode of forging at the temperature of 1170 ± 20 °С and heat treatment (hardening at 1100 ± 5 °С and tempering at 595 ± 5 °С) of steel 4H4N5M4F2 allowed to increase impact strength five times in comparison with cast experimental steel, and also to increase strength threshold of 100 MPa. Forged steel 4H4N5M4F2 has slightly lower heat resistance compared to cast, which hardens at temperatures above 630 °C during operation of the die steel tool. After operation of the extruder wheels made of investigated forged steel and forged steel 4H5MF1S, which was used at the enterprise in copper processing, the properties of both steels were determined. The investigated forged steel 4H4N5M4F2 is characterized by an increase in the strength threshold by 200 MPa and hardness by 6 HRC. After operation (production of 60 tons of copper products of M1 grade) the tool (wheel extruder) from H13 steel (analog 4H5MF1S) had micro and macrocracks on the side and inner parts, and in the investigated steel 4H4N5M4F2 such defects were absent. Thus, the studied steel is characterized by increased stability.

The method of quenching-microstructural analysis, the so-called "stop-quenching", was used to study phase transformations during crystallization of the AK7 casting alloy of the Al-Si-Mg system. The alloy is smelted from scrap and waste, therefore it contains a large amount of impurities, including iron, copper. It was found that the formation of the structure of the AK7 alloy is carried out in the course of the following reactions: 1. Р → Аlα. 2. P → α-(Fe, Mn) 3Si2Al15 + Alα. 3. P → β-FeSiAl5 + Alα. 4. P + β-FeSiAl5 → α-(Fe, Mn, Cu)3Si2Al15. 5. P → β-FeSiAl5 + Si + Alα. 6. P → β-FeSiAl5 + α-(Fe, Mn, Cu)3Si2Al15 + Si + Alα. At the last stages of crystallization, eutectics are formed, which include phases with magnesium and copper: Mg2Si, π-FeMg3Si6Al8, W-Cu2Mg8Si6Al and θ-CuAl2. The transformation P → β + Si + Alα is realized both by the mechanism of cooperative growth of the β, Si, and Alα phases, and by the formation of double eutectics: P → Si + Alα and P → β + Alα, which grow simultaneously in the same temperature range from various centers of crystallization. The four-phase eutectic transformation P → β + α + Si + Alα is carried out according to the type of double or triple eutectic reactions: P → Si + Alα; P → α + Alα; P → β + Alα; β + Si + Alα. The main iron-containing phase in the AK7 alloy is the needle-shaped intermetallic compound β-FeSiAl5 - a stress concentrator, which leads to a decrease in mechanical properties. In this work, the neutralization of the harmful effect of iron was carried out by treating the melt with a unipolar pulsed electric current, under the influence of which the cluster structure of the melt changes. During crystallization, instead of β, a branched phase α is formed. The ratio of intermetallic compounds β and α depends on the processing modes. With optimal parameters of density and current frequency, at which the volume fraction of the branched phase α is the largest, the strength of the AK7 alloy increases by 32.1%, the hardness by 16.7%, and the relative elongation by 2.5 times, bringing its mechanical properties closer to the primary alloy AK7h.

The article presents the results of research on the selection of the saturating mixture optimal composition during chromium plating of gray cast iron. It’s carried out the microstructural studies of the surface layer of gray cast iron SCh 12, obtained using saturating mixtures with different activators and their different percentages. Phase X-ray analysis showed that the obtained coatings on cast iron consist of chromium carbides Cr23C6 and Cr7C3. The carbide zone under the same conditions of diffusion saturation is formed at the amounts of activators exceeding 7%. It is shown that the coefficient of relative wear resistance of gray cast iron after diffusion chromium plating is directly dependent on the depth of the diffusion layer. The corrosion resistance of the coating with increasing thickness of the carbide zone also increases. At the same time, heat resistance decreases sharply with increasing percentage of activator. That is, the phase composition and morphology of the layer structure have a significant influence on the oxidation processes According to the method of experiment simplex-lattice planning, mathematical models of the dependences of the depth of the diffusion layer, corrosion resistance, oxidation, and the coefficient of relative wear resistance on the saturating mixture composition were obtained. Based on the obtained dependences, triple "property-composition" diagrams are constructed. The diagrams analysis confirmed the important role of activators in the process of diffusion chromium plating. It is shown that they promote the formation of active chromium atoms, which provides the formation of a continuous carbide coating. It has been established that during diffusion chromium plating of gray cast iron SCh 12 in order to increase the corrosion resistance of the diffusion layer in the saturating mixture, it is necessary to introduce NH4Cl and NH4F activators in an amount of 10…13%. It also provides with an increase in the coefficient of relative wear resistance of gray cast iron. The introduction into the saturating mixture of NH4Cl and NH4F activators, within 4…6% provides an increase in the scale resistance of the diffusion chromium layer by 10…15 times. The use of NaCl and NaF activators during diffusion chromium plating is impractical because when introduced into the mixture it saturates, in an amount of ≤ 13% they do not give a continuous carbide layer, significantly worsens its performance.

The necessity of increasing the mechanical properties and heat resistance of aviation magnesium case casting is demonstrated. The choice of alloying elements to improve the installation characteristics of the Mg-Al-Zn system is justified. It was found that Ti, Zr and Hf additives in the ML5 alloy in an amount from 0.05 to 1.0 mass. % contribute to reducing the distance between the axes of the dendrites of the 2nd order up to 1.5 times and the size of the micrograin - up to 2 times. The influence of the morphology and topology of the structural components of magnesium alloys on their properties is demonstrated. It was found that microalloying of magnesium alloys Ti, Zr and Hf in an amount from 0.05 to 0.1 mass. % increases the volume percent of intermetallic compounds, displacing them towards smaller size groups with the simultaneous formation of spherical intermetallic compounds located in the center of the grain and serving as additional crystallization centers. It has been established that microalloying of magnesium alloys with refractory metals leads to the formation of complex intermetallic phases enriched with the corresponding alloying elements. It is shown that the optimal additives Ti, Zr and Hf in an amount from 0.05 to 0.1 mass. % help increase strength by ~ 25%, ductility by ~ 2.5 times, and heat resistance by ~ 2 times. New heat-resistant magnesium alloys with a high complex of mechanical properties and heat resistance have been developed. An industrial testing of the production technology of castings made of improved magnesium alloy was carried out in the conditions of the enterprise JSC “Motor Sich”. The use of developed magnesium alloys will improve the reliability and operation safety of aircraft engines.

A rational technology was developed for the production of high-quality cast carbon steel for small castings in small-capacity induction crucible furnaces. In order to determine the carbon and sulfur content, instead of expensive spectral instruments, the cost of which significantly increases the cost of finished products, a metallographic method based on method L (GOST1778-70) for quantitative evaluation of the structural components of steel is proposed. Silicon content was determined using a specially developed device based on the TEMF method. In order to implement metallographic methods of analysis and with the aim of the rapid manufacture of specimens, a mini laboratory was developed and produced, which consists of a small-size cutting machine, a single-spindle grinding and polishing machine with a set of abrasive wheels of different grain sizes and felt polishing discs impregnated with diamond paste, a simplified metallographic microscope MMU-3 with a video camera, a vacuum sampler for sampling liquid metal during smelting process, a device for determining silicon content in steel. Several methods of structural section calculation were tested, but the simplest and proven linear method developed at the «Machines and technology of foundry» Department of National University «Zaporizhzhia Polytechnic» was adopted. The readings of temperature measurements by thermocouple and radiation pyrometers were compared. The latter do not change the solidification conditions of the castings, and the measurement speed is not inferior to thermocouples. Calculation and preparation of the charge were carried out by standard methods, but high precision appliances were used. The studies carried out allowed us to obtain accurate data on the structure and quality indicators of blanks or castings. Testing of the developed technology confirmed the rational consumption of charge materials, guaranteed chemical composition and stable quality indicators of finished products.

The results of studies of porosity, microhardness, microstructure, phase composition, and distribution of alloying elements in samples of VT6 and VT8 titanium alloys are presented. They were synthesized from a mixture of powder components with various modes and subjected to severe plastic deformation by torsion under high pressure with multiple regimes. The effects of sintering time and the regimes of subsequent severe plastic deformation on the microhardness, and it is dispersion through the cross-section of the samples were identified. It was shown that, regardless of the sintering regimes, the microhardness of the samples across the cross-section and does not depend on the processing regimes. Consequently, this serves as an indication of a saturation effect of fragmentation and hardening. The analysis of the porosity of the initial samples concerning both the sintering time and the samples subjected to high pressure torsion was conducted. It was demonstrated that irrespective of the initial value of porosity, severe plastic deformation enables the complete elimination of porosity across the entire cross-section of the samples. It was concluded that the formation of new phases does not occur in the samples of the studied titanium alloys during the process of the severe plastic deformation. It was shown that the samples after sintering obtain a significant chemical heterogeneity, which is effectively eliminated in the process of deformation. The beneficial role of the generated in the samples vortex flows, which facilitate efficient mass transfer was confirmed after adding slowly diffusing chemical elements into the composition of the powder mixture. Considering the physical similarity of the processes which occur in a thin deformable layer of samples during the severe plastic deformation by twist extrusion and high pressure torsion, conclusions on the effectiveness of using twist extrusion to homogenize structural and chemical inhomogeneities in bulk billets of the sintered titanium alloys were drawn.

The improving reliability of stationary gas turbines depends on the guaranteed efficiency of turbine blades tested by the complex effects of high temperatures, mechanical loads, and aggressive medium. Turbine blades are critical parts with complex geometric forms made of nickel-base superalloys. The complexity of forecasting of their lifetime is explained by the data missing on the strength and corrosion resistance during their lifetime. The investigation of their characteristics takes much time and is expensive. Nowadays, the long-term strength calculations are carried out using various methods of extrapolation of the results of short-term tests. In order to forecast the high-temperature characteristics of alloys operating in an oxidizing medium, the time-temperature equations of the long-term strength by Miller-Larson, Cherby-Dorn, Manson-Haferd are most widely used. The studies of the possibility to use parametric time-temperature equations to forecasting the heat resistance of parts tested high-temperature sulfide-oxiding impact are presented. The most reliable parametric method of forecasting the trouble-free operation of the turbine blades has been determined. The analysis of the experimental and calculated values of the long-term strength was showed that under aggressive conditions, the calculation of the time to rupture is possible only for the corrosion-resistant alloys IN-738, ЗМИ-3У. A significant increase in the scattering of experimental and extrapolated features is characteristic, regardless of the method was considered. It was established to make a forecast for ВЖЛ 12У alloy with an increase in extrapolation time to 5,000 hours at 850 °C and above, it is impossible. The maximum resource calculation of trouble-free operation of parts allows not only to save expensive heatproof materials, decrease labor efforts for their manufacture and repair process, but also to increase the reliable operation of gas-turbine engines.