Microstructural and mechanical characteristics of AlSiMnFe alloy processed by equal channel angular pressing

In the present research, equal channel angular pressing (ECAP) was conducted. The defectness degree of the alloy for one pass and maximum strain was determined. Ultra fine grained AlSiMnFe alloy was produced by refining grained annealed bulk by multi-pass ECAP at room temperature. The results reveal two regimes: from 1 to 2 passes the microstructure evolves to a equiaxed of ultrafine grains and from 2 to 4 passes there is no strict change in the average grain size

Impact of Zones with Special Status on the Environment (Experience of Russia and Kazakhstan)

In the article the issues of establishing and functioning of the zones with special economic activity conditions are addressed and their impact on the environment in Russia and Kazakhstan is assessed. The relevance of the subject of the research is determined, on the one hand, by a qualitative change in the role of the environmental issues in the system of values of population of the post-Soviet countries and, on the other hand, by cumulative increase of the negative impact due to the irrational environmental management. Information about the types of special status zones established in these countries is systematized. The key characteristics of these institutional entities are compared, which includes goals and specifics of their development, implemented organizational mechanisms, measures for support of business activities, offered tax incentives and preferences. The authors demonstrate that the adopted accelerated economic growth strategy within the framework of zones with special status is implemented disregarding the environmental effects of their development, which poses serious threats to self-preservation of the society and environment. Common and country-specific risks of functioning of the zones with special economic activity conditions are justified. Factors contributing to inadequate assessment of the negative impact on the environment of industries, created in SEZ were revealed. It is emphasized that the current legal and regulatory framework of these zones in Russia and Kazakhstan is aimed not at the prevention of environmental threats but at the easing of requirements for entities in the field of environmental management. Finally, conclusion is made about the greening opportunities of development of the zones with special economic activity conditions, a necessity to enhance the environmental legislation and mutual "best practices" adoption opportunities in this field in Russia and Kazakhstan. The empirical basis of the analysis is constituted by the results of the studies carried out within the framework of the research work "Enhancement of the State Regulation Policy of Accelerated Clustering of the Industrial Regions" implemented on the grounds of the grant funding of the Ministry of Education and Science of the Republic of Kazakhstan. © 2019 Irina Turgel et al., published by Sciendo 2019.Ministry of Education and Science of the Republic of KazakhstanIn the article the issues of establishing and functioning of the zones with special economic activity conditions are addressed and their impact on the environment in Russia and Kazakhstan is assessed. The relevance of the subject of the research is determined, on the one hand, by a qualitative change in the role of the environmental issues in the system of values of population of the post-soviet countries and, on the other hand, by cumulative increase of the negative impact due to the irrational environmental management. Information about the types of special status zones established in these countries is systematized. The key characteristics of these institutional entities are compared, which includes goals and specifics of their development, implemented organizational mechanisms, measures for support of business activities, offered tax incentives and preferences. The authors demonstrate that the adopted accelerated economic growth strategy within the framework of zones with special status is implemented disregarding the environmental effects of their development, which poses serious threats to self-preservation of the society and environment. Common and country-specific risks of functioning of the zones with special economic activity conditions are justified. Factors contributing to inadequate assessment of the negative impact on the environment of industries, created in SEZ were revealed. It is emphasized that the current legal and regulatory framework of these zones in Russia and Kazakhstan is aimed not at the prevention of environmental threats but at the easing of requirements for entities in the field of environmental management. Finally, conclusion is made about the greening opportunities of development of the zones with special economic activity conditions, a necessity to enhance the environmental legislation and mutual “best practices” adoption opportunities in this field in Russia and Kazakhstan. The empirical basis of the analysis is constituted by the results of the studies carried out within the framework of the research work “Enhancement of the State Regulation Policy of Accelerated Clustering of the Industrial Regions” implemented on the grounds of the grant funding of the Ministry of Education and Science of the Republic of Kazakhstan

Strain state and microstructure evolution of AISI-316 austenitic stainless steel during high-pressure torsion (HPT) process in the new stamp design

The investigation of strain state and microstructure evolution of AISI-316 austenitic stainless steel during highpressure torsion process in the new stamp design was performed. The study using Deform-3D program was conducted. The deformation was carried out at ambient temperature. The results of strain state study showed that after 4 passes the processed workpiece is obtained the level of equivalent strain more than 5. But the distribution of strain has a gradient view in the cross section. The simulation results of the microstructure evolution showed that after 4 passes of deformation the initial grain size of 12 μm can be reduced up to 0,8 μm. But the distribution of grain size in the cross section also has a non - uniform gradient view

Recycling of stainless steel bar scrap by radial-shear rolling to obtain a gradient ultrafine-grained structure

The paper presents the results of the conducted experiments confirmed not only the possibility of processing bar scrap from stainless metals to produce a marketable product, but also confirmed the possibility of obtaining highquality bars with a gradient fine-grained structure and an increased level of mechanical properties. In the course of the research conducted on deformed bar scrap in the form of pins from 12X18N9T austenitic stainless steel at the radial-shear rolling mill the microstructure of two different types was obtained: on the periphery - equiaxed ultrafine- grained structure with a grain size of 0,4 – 0,6 μm; in the axial zone - oriented striped texture. This discrepancy in the structure of the peripheral and axial zones, together with the results of microhardness measuring across the cross section of samples with a total degree of deformation of 44,4 %, indicates the gradient nature of the formed microstructure

Strain state and microstructure evolution of AISI-316 austenitic stainless steel during high-pressure torsion (HPT) process in the new stamp design

The investigation of strain state and microstructure evolution of AISI-316 austenitic stainless steel during highpressure torsion process in the new stamp design was performed. The study using Deform-3D program was conducted. The deformation was carried out at ambient temperature. The results of strain state study showed that after 4 passes the processed workpiece is obtained the level of equivalent strain more than 5. But the distribution of strain has a gradient view in the cross section. The simulation results of the microstructure evolution showed that after 4 passes of deformation the initial grain size of 12 μm can be reduced up to 0,8 μm. But the distribution of grain size in the cross section also has a non - uniform gradient view

Recycling of stainless steel bar scrap by radial-shear rolling to obtain a gradient ultrafine-grained structure

The paper presents the results of the conducted experiments confirmed not only the possibility of processing bar scrap from stainless metals to produce a marketable product, but also confirmed the possibility of obtaining highquality bars with a gradient fine-grained structure and an increased level of mechanical properties. In the course of the research conducted on deformed bar scrap in the form of pins from 12X18N9T austenitic stainless steel at the radial-shear rolling mill the microstructure of two different types was obtained: on the periphery - equiaxed ultrafine- grained structure with a grain size of 0,4 – 0,6 μm; in the axial zone - oriented striped texture. This discrepancy in the structure of the peripheral and axial zones, together with the results of microhardness measuring across the cross section of samples with a total degree of deformation of 44,4 %, indicates the gradient nature of the formed microstructure

Investigation of the effect of combined thermomechanical processing on the brass microstructure evolution and the microhardness change

The article investigates the effect of combined thermomechanical processing, including pre-heat treatment and radial-shear rolling on the brass microstructure evolution and the microhardness change. The microstructure analysis of heat-treated samples according to various modes showed that the most optimal heat treatment before radialshear rolling for L63 brass is annealing at a temperature of 500 °C. As a result of combined thermomechanical processing, a gradient structure was obtained, so in the resulting rods with a diameter of 16 mm in the surface layer, a structure with an average grain size of 9 μm was obtained. In rods with a diameter of 12 mm, a fine–grained, equalgrained structure of 3 μm was obtained in the surface layer

Wear of 16MnCrS5 steel surface layers in the pulsing contact loads

Approaches to actualizing the use of modern alloy steels that are in demand in the Eurasian technological space are proposed. According to the criterion of resistance to contact fatigue, quantitative indicators of wear of the surfacehardened layers of steel 16MnCrS5 were revealed. With the contact stress amplitude up to 950 MPa, the composite material of carbonized and nitrocemented layers is characterized by a period of high resistance with minimal manifestations of structural hardening by the mechanism of softening of the material. The obtained composite material with carbonized and nitrocemented layers is characterized by a period of high resistance up to 15 000 cycles

Wear of 16MnCrS5 steel surface layers in the pulsing contact loads

Approaches to actualizing the use of modern alloy steels that are in demand in the Eurasian technological space are proposed. According to the criterion of resistance to contact fatigue, quantitative indicators of wear of the surfacehardened layers of steel 16MnCrS5 were revealed. With the contact stress amplitude up to 950 MPa, the composite material of carbonized and nitrocemented layers is characterized by a period of high resistance with minimal manifestations of structural hardening by the mechanism of softening of the material. The obtained composite material with carbonized and nitrocemented layers is characterized by a period of high resistance up to 15 000 cycles

Effect of surface modification of 5KHV2S steel on the mechanism and intensity of contact wear

The paper presents the experimental study of the contact wear of 5KHV2S steel after surface modification. It is shown that without hardening of the surface layer, 5KHV2S steel is capable of satisfactory operation when a pulsating contact stress of 970 MPa is applied. The most qualitative type of surface modification is the hardening of the surface layer by nitrocementation carried out before quenching and tempering. The proposed technology of volumetric- surface hardening, including forging in a new forging tool, chemical-thermal treatment, quenching and lowtemperature tempering, provided the possibility of increasing the pulsating contact stress to 1 100 MPa, and the operation period during the first 13 000 loading cycles gives wear of the working surface no more than 0,1 mm