Pub Date : 2023-01-01DOI: 10.30791/1028-978x-2023-2-44-53
D. Mayorov, Yuriy O. Velyaev
Samples of amorphous silicon dioxide (SiO2) were obtained by acid decomposition of mineral raw materials (nepheline). Their physico-chemical, acid-base and structural-surface properties have been studied by methods of chemical analysis, Parks, BET, BJH, etc. It was found that in terms of the content of impurities, the pH of the aqueous extract, the pH values of the isoionic point and the zero charge point, the SiO2 samples obtained are almost identical to pyrogenic amorphous silicon dioxide obtained from reactive raw materials (pharmaceutical preparation “Polysorb PM”) and have an increased specific external surface compared to “Polysorb PM” (in 1.1 – 1.9 times) and specific pore volume (1.4 times). Based on the obtained values of the specific capacity of the adsorption monolayer of the surface of SiO2 samples and the change in Gibbs energy (ΔG0) during sorption, it is concluded that the method of their preparation does not significantly affect the physicochemical properties of their surfaces and the mechanism of nitrogen sorption. Based on the results obtained, an assumption is made about the prospects of using silicon dioxide, obtained on the basis of acid processing of mineral raw materials, as an enterosorbent in therapeutic practice.
{"title":"On the prospects of using silicon dioxide obtained from mineral raw materials as an enterosorbent","authors":"D. Mayorov, Yuriy O. Velyaev","doi":"10.30791/1028-978x-2023-2-44-53","DOIUrl":"https://doi.org/10.30791/1028-978x-2023-2-44-53","url":null,"abstract":"Samples of amorphous silicon dioxide (SiO2) were obtained by acid decomposition of mineral raw materials (nepheline). Their physico-chemical, acid-base and structural-surface properties have been studied by methods of chemical analysis, Parks, BET, BJH, etc. It was found that in terms of the content of impurities, the pH of the aqueous extract, the pH values of the isoionic point and the zero charge point, the SiO2 samples obtained are almost identical to pyrogenic amorphous silicon dioxide obtained from reactive raw materials (pharmaceutical preparation “Polysorb PM”) and have an increased specific external surface compared to “Polysorb PM” (in 1.1 – 1.9 times) and specific pore volume (1.4 times). Based on the obtained values of the specific capacity of the adsorption monolayer of the surface of SiO2 samples and the change in Gibbs energy (ΔG0) during sorption, it is concluded that the method of their preparation does not significantly affect the physicochemical properties of their surfaces and the mechanism of nitrogen sorption. Based on the results obtained, an assumption is made about the prospects of using silicon dioxide, obtained on the basis of acid processing of mineral raw materials, as an enterosorbent in therapeutic practice.","PeriodicalId":20003,"journal":{"name":"Perspektivnye Materialy","volume":"58 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87644598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.30791/1028-978x-2023-7-65-72
S. Eremin, V. N. Anikin, D. Rudenko, A. M. Kolesnikova, Y. Sobolev, V. Kuzin, M. Fedorov, N. A. Revyakina
In the work, experiments were carried out on the production and testing of hard alloys from powders of the VK10KHOM and VRK15 grades coated with multigraphene obtained by the electrochemical method. Samples with multigraphene were sintered under standard conditions for grades VK10KHOM and VRK15. In the weight ratio, the amount of multigraphene was 0.1 wt. % for the VK10KHOM grade alloy and 0.1 wt. % and 0.5 wt. % for the VRK15 grade. Friction tests of VK10KhOM samples showed that the width of the wear areas of samples with multigraphene is 8 % less than in the original ones. At 0.1 wt. % graphene, the density of the VK10KHOM grade is 14.5 and VRK15 is 14.0, and the porosity is 0.02 % and 2 %, respectively. Comparative tests were carried out on cutting titanium grade VT-3. As a result of cutting, it was found that the coating of powders with multigraphene increases the resistance of carbide inserts of both grades. It is shown that for VRK15 the plate durability increased by 4 times, and for the VK10KHOM grade it was not possible to establish the plate failure time. The increase in wear resistance is presumably caused by a decrease in the coefficient of friction due to multigraphene, which, dissolving in the hard alloy, precipitates in the form of nanographite clusters.
{"title":"Effect of multigraphene on the resistance of plates from hard alloys","authors":"S. Eremin, V. N. Anikin, D. Rudenko, A. M. Kolesnikova, Y. Sobolev, V. Kuzin, M. Fedorov, N. A. Revyakina","doi":"10.30791/1028-978x-2023-7-65-72","DOIUrl":"https://doi.org/10.30791/1028-978x-2023-7-65-72","url":null,"abstract":"In the work, experiments were carried out on the production and testing of hard alloys from powders of the VK10KHOM and VRK15 grades coated with multigraphene obtained by the electrochemical method. Samples with multigraphene were sintered under standard conditions for grades VK10KHOM and VRK15. In the weight ratio, the amount of multigraphene was 0.1 wt. % for the VK10KHOM grade alloy and 0.1 wt. % and 0.5 wt. % for the VRK15 grade. Friction tests of VK10KhOM samples showed that the width of the wear areas of samples with multigraphene is 8 % less than in the original ones. At 0.1 wt. % graphene, the density of the VK10KHOM grade is 14.5 and VRK15 is 14.0, and the porosity is 0.02 % and 2 %, respectively. Comparative tests were carried out on cutting titanium grade VT-3. As a result of cutting, it was found that the coating of powders with multigraphene increases the resistance of carbide inserts of both grades. It is shown that for VRK15 the plate durability increased by 4 times, and for the VK10KHOM grade it was not possible to establish the plate failure time. The increase in wear resistance is presumably caused by a decrease in the coefficient of friction due to multigraphene, which, dissolving in the hard alloy, precipitates in the form of nanographite clusters.","PeriodicalId":20003,"journal":{"name":"Perspektivnye Materialy","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83724516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.30791/1028-978x-2023-3-43-48
A. Akhmetov, Z. Eremeeva
In this work, a study was made of the change in the microstructure of a hot-pressed billet from a powder mixture of high-speed steel grade R6M5K5 containing a diffusion-alloyed additive based on tungsten, molybdenum, cobalt and iron after heat treatment processes: quenching in oil at a temperature of 1230 °C and double high tempering at 550 °C for 60 min. The study was carried out using electron microscopy and energy dispersive X-ray spectroscopy. After quenching, dissolution of small-sized carbides in the matrix is observed, and after two-fold tempering, secondary carbides of the M6C and MC types are already precipitated. The second type of carbides is formed from a separate structural component — a phase based on ferrovanadium, whose powder was used as a source of vanadium. Also, cobalt is unevenly distributed in the matrix, which is concentrated in a separate phase based on a diffusion-alloyed additive. These phases practically do not dissolve, and are quite stable under these conditions of hot pressing and heat treatment. It is shown that the hardness of blanks changes from 63.1 HRA after hot pressing to 67.2 HRA after quenching and up to 66.3 HRA after double tempering.
{"title":"Changes in the microstructure and hardness after heat treatment of a billet made of powder high-speed steel R6M5K5 containing a diffusion-alloyed additive","authors":"A. Akhmetov, Z. Eremeeva","doi":"10.30791/1028-978x-2023-3-43-48","DOIUrl":"https://doi.org/10.30791/1028-978x-2023-3-43-48","url":null,"abstract":"In this work, a study was made of the change in the microstructure of a hot-pressed billet from a powder mixture of high-speed steel grade R6M5K5 containing a diffusion-alloyed additive based on tungsten, molybdenum, cobalt and iron after heat treatment processes: quenching in oil at a temperature of 1230 °C and double high tempering at 550 °C for 60 min. The study was carried out using electron microscopy and energy dispersive X-ray spectroscopy. After quenching, dissolution of small-sized carbides in the matrix is observed, and after two-fold tempering, secondary carbides of the M6C and MC types are already precipitated. The second type of carbides is formed from a separate structural component — a phase based on ferrovanadium, whose powder was used as a source of vanadium. Also, cobalt is unevenly distributed in the matrix, which is concentrated in a separate phase based on a diffusion-alloyed additive. These phases practically do not dissolve, and are quite stable under these conditions of hot pressing and heat treatment. It is shown that the hardness of blanks changes from 63.1 HRA after hot pressing to 67.2 HRA after quenching and up to 66.3 HRA after double tempering.","PeriodicalId":20003,"journal":{"name":"Perspektivnye Materialy","volume":"124 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87897830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.30791/1028-978x-2023-5-22-34
I. Arutyunyan, A. Dunaev, E. M. Trifanova, M. Khvorostina, A. Elchaninov, A. Soboleva, T. Fatkhudinov, V. Popov
The biocompatibility of polylactic-co-glycolic acid (PLGA) scaffolds for tissue engineering constructions can be significantly improved by autologous mesenchymal stem cells (MSCs) colonization. However, the features of the cell colonization procedure can generally affect the changes in the physical and mechanical properties of these scaffolds, which are mostly determined by their architectonics. To study this issue, in this work, we have formed and investigated three types of experimental PLGA samples: 1). molded monolithic blocks; 2). porous scaffolds formed by plasticization in supercritical CO2 followed by foaming; and 3). electrospun fibrous non-woven scaffolds. The quantitative XTT test showed the nontoxicity of all studied samples, as well as the greater efficiency of the dynamic cell colonization method compared to the static one. After 48 hours of samples incubation with cell cultures, their physical and mechanical properties were noted to change both at macro- and microlevels. These changes, in our opinion, occur due to the processes of hydrolytic and enzymatic PLGA hydrolysis, as well as the effect of adhered MSCs on the scaffold internal structure and surface morphology. Similar transformations of certain physical, mechanical and structural properties of scaffolds based on other biodegradable polymers or their compositions can also occur as a result of their colonization with various cell cultures, which should be taken into account when applying the scaffolds to develop tissue engineering constructions.
{"title":"Effects of mesenchymal stem cells on the physical and mechanical properties of polyester scaffolds of different architectonics","authors":"I. Arutyunyan, A. Dunaev, E. M. Trifanova, M. Khvorostina, A. Elchaninov, A. Soboleva, T. Fatkhudinov, V. Popov","doi":"10.30791/1028-978x-2023-5-22-34","DOIUrl":"https://doi.org/10.30791/1028-978x-2023-5-22-34","url":null,"abstract":"The biocompatibility of polylactic-co-glycolic acid (PLGA) scaffolds for tissue engineering constructions can be significantly improved by autologous mesenchymal stem cells (MSCs) colonization. However, the features of the cell colonization procedure can generally affect the changes in the physical and mechanical properties of these scaffolds, which are mostly determined by their architectonics. To study this issue, in this work, we have formed and investigated three types of experimental PLGA samples: 1). molded monolithic blocks; 2). porous scaffolds formed by plasticization in supercritical CO2 followed by foaming; and 3). electrospun fibrous non-woven scaffolds. The quantitative XTT test showed the nontoxicity of all studied samples, as well as the greater efficiency of the dynamic cell colonization method compared to the static one. After 48 hours of samples incubation with cell cultures, their physical and mechanical properties were noted to change both at macro- and microlevels. These changes, in our opinion, occur due to the processes of hydrolytic and enzymatic PLGA hydrolysis, as well as the effect of adhered MSCs on the scaffold internal structure and surface morphology. Similar transformations of certain physical, mechanical and structural properties of scaffolds based on other biodegradable polymers or their compositions can also occur as a result of their colonization with various cell cultures, which should be taken into account when applying the scaffolds to develop tissue engineering constructions.","PeriodicalId":20003,"journal":{"name":"Perspektivnye Materialy","volume":"72 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88236543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.30791/1028-978x-2023-4-68-75
E. Simakina, E. Y. Liberman, B. S. Kleusov, T. Kon’kova, V. N. Grunskii, A. N. Morozov, A. V. Denisenko
Fluorite-like solid solutions of Ce0.9Sn0.1O2 and Ce0.8Sn0.1Zr0.1O2 are synthesized by co-precipitation using ammonium carbonate as a precipitant. The samples were characterized by X-ray phase analysis, electron microscopy, energy dispersive analysis, low-temperature nitrogen adsorption, and gas chromatography. It is shown that the formation of solid solutions occurs even at an annealing temperature of 550°C. In this case, the formation of lamellar particles occurs, the size of which, according to SEM data, is 4 μm. The synthesized materials have a mesoporous structure. The specific surface area of Ce0.9Sn0.1O2 samples is 80.6 m2/g, Ce0.8Zr0.1Sn0.1O2 is 76.3 m2/g. Carrying out the calcination at a temperature of 800 °C leads to an increase in the particle size up to 8 – 10 µm. The highest specific surface area of 15.3 m2/g is typical for the Ce0.8Zr0.1Sn0.1O2 sample, which is due to the presence of zirconium ions in its composition. The synthesized compositions demonstrated high activity in CO oxidation. The maximum catalytic activity was observed for the bicomponent system Ce0.9Sn0.1O2: T50% — 180°C, T90% — 236 °C. For samples calcined at a temperature of 800 °C, the most active is Ce0.8Zr0.1Sn0.1O2, which is due to the formation of a more thermally stable system compared to cerium dioxide and Ce0.9Sn0.1O2. To increase the thermal stability, it is advisable to dope the bicomponent composition Ce0.9Sn0.1O2 with Zr+4 ions.
{"title":"Synthesis and catalytic activity of highly dispersed solid solutions Ce0,9Sn0,1O2 and Ce0,8Sn0,1Zr0,1O2 in CO oxidation","authors":"E. Simakina, E. Y. Liberman, B. S. Kleusov, T. Kon’kova, V. N. Grunskii, A. N. Morozov, A. V. Denisenko","doi":"10.30791/1028-978x-2023-4-68-75","DOIUrl":"https://doi.org/10.30791/1028-978x-2023-4-68-75","url":null,"abstract":"Fluorite-like solid solutions of Ce0.9Sn0.1O2 and Ce0.8Sn0.1Zr0.1O2 are synthesized by co-precipitation using ammonium carbonate as a precipitant. The samples were characterized by X-ray phase analysis, electron microscopy, energy dispersive analysis, low-temperature nitrogen adsorption, and gas chromatography. It is shown that the formation of solid solutions occurs even at an annealing temperature of 550°C. In this case, the formation of lamellar particles occurs, the size of which, according to SEM data, is 4 μm. The synthesized materials have a mesoporous structure. The specific surface area of Ce0.9Sn0.1O2 samples is 80.6 m2/g, Ce0.8Zr0.1Sn0.1O2 is 76.3 m2/g. Carrying out the calcination at a temperature of 800 °C leads to an increase in the particle size up to 8 – 10 µm. The highest specific surface area of 15.3 m2/g is typical for the Ce0.8Zr0.1Sn0.1O2 sample, which is due to the presence of zirconium ions in its composition. The synthesized compositions demonstrated high activity in CO oxidation. The maximum catalytic activity was observed for the bicomponent system Ce0.9Sn0.1O2: T50% — 180°C, T90% — 236 °C. For samples calcined at a temperature of 800 °C, the most active is Ce0.8Zr0.1Sn0.1O2, which is due to the formation of a more thermally stable system compared to cerium dioxide and Ce0.9Sn0.1O2. To increase the thermal stability, it is advisable to dope the bicomponent composition Ce0.9Sn0.1O2 with Zr+4 ions.","PeriodicalId":20003,"journal":{"name":"Perspektivnye Materialy","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76963695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.30791/1028-978x-2023-2-77-86
N. V. Shadrinov, A. A. Borisova, A. R. Khaldeeva, K. P. Antoev
The results of a study of the influence of the mixing mode and curing system on the properties of low temperature and oil resistant rubber based on a composition of butadiene-nitrile rubber (BNKS-18AMN) and ultra-high molecular weight polyethylene (GUR 4113) are presented. Different ways of UHMWPE introducing into the rubber compound are considered: mixing before and after the introduction the main ingredients of the rubber compound at temperatures up to 80 °C (below the melting point of UHMWPE) and preliminary high-temperature (160 °C) mixing of rubber and UHMWPE. It was found that the preliminary high temperature mixing of rubber with UHMWPE leads to a decrease in the viscosity of the rubber compound, as well as a reduction in the scorch time and the achievement of an optimum vulcanization but does not lead to significant changes in the physical and mechanical properties and oil resistance of vulcanizates. The study of the influence of the curing system showed the effectiveness of using a combined sulfur-peroxide curing system, which is manifested in the improvement of the technical properties of vulcanizates, which is largely due to an increase in the density of rubber crosslinking through the formation of stronger and more heat-resistant C-C bonds. It has been shown that the best set of technical properties of vulcanizates, including high frost-resistance, physical and mechanical properties, resistance to hydrocarbon environment and retention of properties after thermal exposure, is achieved when using the sulfur-peroxide combination S/DCP – 1/2.
{"title":"Influence of the technological mode of mixing and curing system on the properties of compositions based on nitrile rubber and ultrahigh molecular weight polyethylene","authors":"N. V. Shadrinov, A. A. Borisova, A. R. Khaldeeva, K. P. Antoev","doi":"10.30791/1028-978x-2023-2-77-86","DOIUrl":"https://doi.org/10.30791/1028-978x-2023-2-77-86","url":null,"abstract":"The results of a study of the influence of the mixing mode and curing system on the properties of low temperature and oil resistant rubber based on a composition of butadiene-nitrile rubber (BNKS-18AMN) and ultra-high molecular weight polyethylene (GUR 4113) are presented. Different ways of UHMWPE introducing into the rubber compound are considered: mixing before and after the introduction the main ingredients of the rubber compound at temperatures up to 80 °C (below the melting point of UHMWPE) and preliminary high-temperature (160 °C) mixing of rubber and UHMWPE. It was found that the preliminary high temperature mixing of rubber with UHMWPE leads to a decrease in the viscosity of the rubber compound, as well as a reduction in the scorch time and the achievement of an optimum vulcanization but does not lead to significant changes in the physical and mechanical properties and oil resistance of vulcanizates. The study of the influence of the curing system showed the effectiveness of using a combined sulfur-peroxide curing system, which is manifested in the improvement of the technical properties of vulcanizates, which is largely due to an increase in the density of rubber crosslinking through the formation of stronger and more heat-resistant C-C bonds. It has been shown that the best set of technical properties of vulcanizates, including high frost-resistance, physical and mechanical properties, resistance to hydrocarbon environment and retention of properties after thermal exposure, is achieved when using the sulfur-peroxide combination S/DCP – 1/2.","PeriodicalId":20003,"journal":{"name":"Perspektivnye Materialy","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83476788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.30791/1028-978x-2023-6-80-84
M. Alymov
The method of hot gas extrusion differs from other methods of metal pressure treatment in that the processed material is subjected to intense plastic deformation by extrusion under conditions of high isostatic pressure of inert gas and heating in the area of plastic deformation. The method makes it possible to process powder materials, while inevitably there is a need to control mechanical properties by controlling porosity and pressure inside the pores. The paper presents a method for calculating the pressure inside the pores from the minimum size of the closed pore. The pore pressure was evaluated on materials obtained by the consolidation of nickel nanopowders by hot gas extrusion. Quantitative processing of the material cross-section view images obtained by scanning electron microscopy showed that the minimum pore size is 220 nm. The formula for calculating the pore pressure is derived from the formula for calculating the critical pore radius. It takes into account the external impact pressure (the gas pressure during the extrusion process was equal to 400 MPa), the surface tension coefficient and the yield strength of nickel (at the extrusion start temperature of 910 °С), as well as the minimum pore radius. The proposed method for calculating the pressure inside a closed pore will allow us to evaluate the mechanical properties of materials obtained by various methods of powder metallurgy.
{"title":"Porosity of nickel nanopowder compacts consolidated by gas extrusion","authors":"M. Alymov","doi":"10.30791/1028-978x-2023-6-80-84","DOIUrl":"https://doi.org/10.30791/1028-978x-2023-6-80-84","url":null,"abstract":"The method of hot gas extrusion differs from other methods of metal pressure treatment in that the processed material is subjected to intense plastic deformation by extrusion under conditions of high isostatic pressure of inert gas and heating in the area of plastic deformation. The method makes it possible to process powder materials, while inevitably there is a need to control mechanical properties by controlling porosity and pressure inside the pores. The paper presents a method for calculating the pressure inside the pores from the minimum size of the closed pore. The pore pressure was evaluated on materials obtained by the consolidation of nickel nanopowders by hot gas extrusion. Quantitative processing of the material cross-section view images obtained by scanning electron microscopy showed that the minimum pore size is 220 nm. The formula for calculating the pore pressure is derived from the formula for calculating the critical pore radius. It takes into account the external impact pressure (the gas pressure during the extrusion process was equal to 400 MPa), the surface tension coefficient and the yield strength of nickel (at the extrusion start temperature of 910 °С), as well as the minimum pore radius. The proposed method for calculating the pressure inside a closed pore will allow us to evaluate the mechanical properties of materials obtained by various methods of powder metallurgy.","PeriodicalId":20003,"journal":{"name":"Perspektivnye Materialy","volume":"81 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85528597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.30791/1028-978x-2023-3-64-74
T. I. Devyatkina, R. V. Taranets, V. V. Rogozhin, V. Isaev
A comparative analysis of the influence of the structure of azo compounds (on the example of methyl red (MKR) and nitroso-p-salt (NRS)) was carried out during copper plating of anodized aluminum alloys, on the microstructure, micro-roughness and quality of deposited copper coatings. It is shown that the choice of azo dye significantly depends on the charge of the surface of the oxide film in the solutions used. It is shown that the dyes used should have at least two functional groups in their composition, one of which should ensure the formation of complexes with copper ions, and the other – their adhesion to the surface of the oxide film due to the forces of electrostatic interaction. The adsorption of azo compounds changes the structure of the double electric layer at the film – electrolyte interface, which affects the speed of the copper plating process. At the same time, the mobility of the formed complexes in the adsorption layer increases, which leads to a better opening of the film surface. The studied indicators (dyes) positively affected the structure of the copper coating (eliminated defects and made it fine-crystalline), and also significantly smoothed the surface of the copper coating. The advantage of using the NRS over the MKR was revealed, which allowed not only to obtain a high-quality coating, but also to significantly intensify the copper plating process. A new composition of copper sulfuric acid electrolyte for coating anodized aluminum alloys at elevated cathode current densities with preservation of fine-crystalline structure and smoothed surface is proposed.
{"title":"The influence of the structure of azo compounds on the deposition process and the quality of copper coatings on Anodized aluminum alloys","authors":"T. I. Devyatkina, R. V. Taranets, V. V. Rogozhin, V. Isaev","doi":"10.30791/1028-978x-2023-3-64-74","DOIUrl":"https://doi.org/10.30791/1028-978x-2023-3-64-74","url":null,"abstract":"A comparative analysis of the influence of the structure of azo compounds (on the example of methyl red (MKR) and nitroso-p-salt (NRS)) was carried out during copper plating of anodized aluminum alloys, on the microstructure, micro-roughness and quality of deposited copper coatings. It is shown that the choice of azo dye significantly depends on the charge of the surface of the oxide film in the solutions used. It is shown that the dyes used should have at least two functional groups in their composition, one of which should ensure the formation of complexes with copper ions, and the other – their adhesion to the surface of the oxide film due to the forces of electrostatic interaction. The adsorption of azo compounds changes the structure of the double electric layer at the film – electrolyte interface, which affects the speed of the copper plating process. At the same time, the mobility of the formed complexes in the adsorption layer increases, which leads to a better opening of the film surface. The studied indicators (dyes) positively affected the structure of the copper coating (eliminated defects and made it fine-crystalline), and also significantly smoothed the surface of the copper coating. The advantage of using the NRS over the MKR was revealed, which allowed not only to obtain a high-quality coating, but also to significantly intensify the copper plating process. A new composition of copper sulfuric acid electrolyte for coating anodized aluminum alloys at elevated cathode current densities with preservation of fine-crystalline structure and smoothed surface is proposed.","PeriodicalId":20003,"journal":{"name":"Perspektivnye Materialy","volume":"41 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85128647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.30791/1028-978x-2023-1-80-88
P. N. Petrova, M. Markova, A. Fedorov
This paper presents the results of research on the development of technology for plastic deformation of polymer blanks based on polytetrafluoroethylene (PTFE) and carbon fibers of the UVIS-AK-P brand in order to increase their strength and creep resistance. The dependence of the physico-mechanical and tribotechnical characteristics of the obtained composites is investigated and compared with a composite of the same composition, but obtained using a previously developed technology. It is established that the use of plastic deformation technology for the properties of PCM based on PTFE and carbon fibers of the brand UVIS-AK-P is an effective solution for obtaining high-strength, wear-resistant composites, characterized by increased resistance to tensile loads. The developed composites obtained using plastic deformation are characterized by 3 times increased tensile strength and 22 – 29 times reduced creep compared to the original PTFE obtained by standard technology. Structural studies of the technology of plastic deformation of polymer blanks have shown that this technology leads to the orientation of the carbon fiber (CF) in the direction of the flow of the material and a change in the spiral conformation of macromolecules with a transition to a more stable conformation, which favorably affects its operational properties. The use of this method will make it possible to obtain high-strength polymer materials with increased resistance to deformation, promising for use for loading schemes with high tensile loads.
{"title":"High-strength fluoroplastic composites with increased resistance to deformation under load","authors":"P. N. Petrova, M. Markova, A. Fedorov","doi":"10.30791/1028-978x-2023-1-80-88","DOIUrl":"https://doi.org/10.30791/1028-978x-2023-1-80-88","url":null,"abstract":"This paper presents the results of research on the development of technology for plastic deformation of polymer blanks based on polytetrafluoroethylene (PTFE) and carbon fibers of the UVIS-AK-P brand in order to increase their strength and creep resistance. The dependence of the physico-mechanical and tribotechnical characteristics of the obtained composites is investigated and compared with a composite of the same composition, but obtained using a previously developed technology. It is established that the use of plastic deformation technology for the properties of PCM based on PTFE and carbon fibers of the brand UVIS-AK-P is an effective solution for obtaining high-strength, wear-resistant composites, characterized by increased resistance to tensile loads. The developed composites obtained using plastic deformation are characterized by 3 times increased tensile strength and 22 – 29 times reduced creep compared to the original PTFE obtained by standard technology. Structural studies of the technology of plastic deformation of polymer blanks have shown that this technology leads to the orientation of the carbon fiber (CF) in the direction of the flow of the material and a change in the spiral conformation of macromolecules with a transition to a more stable conformation, which favorably affects its operational properties. The use of this method will make it possible to obtain high-strength polymer materials with increased resistance to deformation, promising for use for loading schemes with high tensile loads.","PeriodicalId":20003,"journal":{"name":"Perspektivnye Materialy","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79953190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.30791/1028-978x-2023-3-75-84
E. Ermakova, S. S. Strelnikova, A. Anokhin, A. A. Konovalov, О. S. Antonova, M. Chuvikina
The paper focuses on lanthanum cobaltite micropowders LaCoO3-δ (LCO) synthesized by the sol-gel method using polyvinylpyrrolidone (PVP) as gelling agent. The PVP content has been varied from 0.5 to 5.0 wt. % when ionic solutions of the soluble raw components were prepared. The gels were dried in a microwave oven at microwave power 90 W for 2 h to evaporate water. Xerogels were thermally treated in a muffle furnace at temperatures 800°C and 900°C, the maximum holding time was 10 h and 30 h. After heat treatment of Xerogels at 800°C for 10 h LCO micropowders were slightly aggregated and particle size were in the range from 0.24 to 0.38 µm as well as specific surface area was in the range from 2.60 to 4.10 m2/g. After heat treatment 900°C for 10 h the specific surface area range of LCO micropowders decreased from 1.00 to 3.20 m2/g, but particle size range slightly increased from 0.31 up to 1.0 µm. Xerogels heat treatment at temperature 900° C for 30 h resulted to particles size range growing from 0.50 to 1.25 μm, and the specific surface area was 2.00 m2/g for all LCO micropowders. There was no effect of PVP content in the ionic solution on phase composition for all heat treated LCO micropowders.
{"title":"Investigation of the polyvinylpyrrolidone amount as gelling agent to lanthanum cobaltite micropowders synthesize by sol-gel method","authors":"E. Ermakova, S. S. Strelnikova, A. Anokhin, A. A. Konovalov, О. S. Antonova, M. Chuvikina","doi":"10.30791/1028-978x-2023-3-75-84","DOIUrl":"https://doi.org/10.30791/1028-978x-2023-3-75-84","url":null,"abstract":"The paper focuses on lanthanum cobaltite micropowders LaCoO3-δ (LCO) synthesized by the sol-gel method using polyvinylpyrrolidone (PVP) as gelling agent. The PVP content has been varied from 0.5 to 5.0 wt. % when ionic solutions of the soluble raw components were prepared. The gels were dried in a microwave oven at microwave power 90 W for 2 h to evaporate water. Xerogels were thermally treated in a muffle furnace at temperatures 800°C and 900°C, the maximum holding time was 10 h and 30 h. After heat treatment of Xerogels at 800°C for 10 h LCO micropowders were slightly aggregated and particle size were in the range from 0.24 to 0.38 µm as well as specific surface area was in the range from 2.60 to 4.10 m2/g. After heat treatment 900°C for 10 h the specific surface area range of LCO micropowders decreased from 1.00 to 3.20 m2/g, but particle size range slightly increased from 0.31 up to 1.0 µm. Xerogels heat treatment at temperature 900° C for 30 h resulted to particles size range growing from 0.50 to 1.25 μm, and the specific surface area was 2.00 m2/g for all LCO micropowders. There was no effect of PVP content in the ionic solution on phase composition for all heat treated LCO micropowders.","PeriodicalId":20003,"journal":{"name":"Perspektivnye Materialy","volume":"47 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89749757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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