Pub Date : 2022-12-15DOI: 10.17212/1994-6309-2022-24.4-18-32
N. Ulakhanov, A. Tikhonov, U. Mishigdorzhiyn, V. Ivancivsky, N. Vakhrushev
Introduction. Diffusion boroaluminizing provides improved performance properties of the die steels’ surface such as wear resistance, high hardness, and corrosion resistance. Surface hardening can significantly contribute to the occurrence of technological residual stresses (TRS) on the surface. Currently, there are no studies on the topic of the stress state of diffusion boroaluminizing. The purpose of this work is to develop a method for determining the TRS and a nature of its distribution in the diffusion layers on the surface of 5CrNiMo and 3Cr2W8V die steels after boroaluminizing by a mechanical method. The paper considers the results of experimental studies on the determination of the normal components of TRS by the mechanical method in diffusion layers of die steels. The conducted studies showed that the formation of unfavorable tensile TRS occurs along the depth of the hardened layer in the case of the investigated TCT method and types of steels. Results and discussions. The main approaches for determining the TRS in the surface layer of 3Cr2W8V and 5CrNiMo die steels after TCT are considered. Problems in the determination of TRS by the mechanical method on the UDINON-2 unit are identified, and its solution is proposed. The efficiency of using the anodic dissolution method for the continuous removal of stressed layers during the TRS study by the mechanical method on the UDION-2 unit is shown. The optimal electrolyte composition is selected for the process of anodic dissolution consisting of: NaNO3 – 60 g/l; NaNO2 – 5 g/l; Na2CO3 – 5 g/l; C3H8O3 – 15 g/l; H2O – the rest. The distributions of the normal TRS components in the diffusion layer of die steel specimens are revealed. It is established that, during the TCT of these steels predominantly tensile TRS are formed in the surface layer. Further research will be aimed at developing measures to reduce tensile TRS during diffusion boroaluminizing of die steels.
{"title":"The features of residual stresses investigation in the hardened surface layer of die steels after diffusion boroaluminizing","authors":"N. Ulakhanov, A. Tikhonov, U. Mishigdorzhiyn, V. Ivancivsky, N. Vakhrushev","doi":"10.17212/1994-6309-2022-24.4-18-32","DOIUrl":"https://doi.org/10.17212/1994-6309-2022-24.4-18-32","url":null,"abstract":"Introduction. Diffusion boroaluminizing provides improved performance properties of the die steels’ surface such as wear resistance, high hardness, and corrosion resistance. Surface hardening can significantly contribute to the occurrence of technological residual stresses (TRS) on the surface. Currently, there are no studies on the topic of the stress state of diffusion boroaluminizing. The purpose of this work is to develop a method for determining the TRS and a nature of its distribution in the diffusion layers on the surface of 5CrNiMo and 3Cr2W8V die steels after boroaluminizing by a mechanical method. The paper considers the results of experimental studies on the determination of the normal components of TRS by the mechanical method in diffusion layers of die steels. The conducted studies showed that the formation of unfavorable tensile TRS occurs along the depth of the hardened layer in the case of the investigated TCT method and types of steels. Results and discussions. The main approaches for determining the TRS in the surface layer of 3Cr2W8V and 5CrNiMo die steels after TCT are considered. Problems in the determination of TRS by the mechanical method on the UDINON-2 unit are identified, and its solution is proposed. The efficiency of using the anodic dissolution method for the continuous removal of stressed layers during the TRS study by the mechanical method on the UDION-2 unit is shown. The optimal electrolyte composition is selected for the process of anodic dissolution consisting of: NaNO3 – 60 g/l; NaNO2 – 5 g/l; Na2CO3 – 5 g/l; C3H8O3 – 15 g/l; H2O – the rest. The distributions of the normal TRS components in the diffusion layer of die steel specimens are revealed. It is established that, during the TCT of these steels predominantly tensile TRS are formed in the surface layer. Further research will be aimed at developing measures to reduce tensile TRS during diffusion boroaluminizing of die steels.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44925748","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 : 2022-12-15DOI: 10.17212/1994-6309-2022-24.4-151-164
N. Saprykina, V. Chebodaeva, A. Saprykin, Y. Sharkeev, E. Ibragimov, Taisiya Guseva
Introduction. The technology of selective laser melting is one of the key technologies in Industry 4.0, which allows manufacturing products of any complex geometric shape, reducing significantly the amount of material used, reducing the lead time and obtaining a new alloy from elementary powders in the melting process. To understand the process of alloy formation under laser exposure, it is necessary to know the initial data of powders, which significantly affect the quality of the products obtained. The purpose of this study is to determine the requirements for the structural-phase state, elemental composition of aluminum, silicon and magnesium powders and further preparation of Al-Si-Mg (Al — 91 wt.%, Si — 8 wt.%, Mg — 1 wt.%) powder mixture for laser synthesis. The initial powders of aluminum PA-4 (GOST 6058-73), silicon (GOST 2169-69) and magnesium MPF-4 (GOST 6001-79) and powder composition Al-Si-Mg are studied using X-ray diffraction and X-ray phase analysis. The shape and sizes of particles are determined by the studies of raster electronic images. By the method of selective laser melting, samples are obtained from a powder composition under constant and pulsed laser exposure. The composition is prepared by mixing powders in a globe mill. Results and discussion. It is shown that the initial powders of aluminum, silicon and magnesium are single-phase. Particles with a size of 20–64 µm, recommended for selective laser melting, are used to obtain a powder composition. By mixing the powders for one hour, spherical particles are obtained, which is preferable for laser melting. The results of grinding the samples after laser melting showed that the samples obtained under constant laser exposure at the following mode parameters: P = 80 W, V = 300 mm/s, s = 90 μm, h = 25 μm have the greatest mechanical strength. Conclusions. The described study shows the possibility of synthesizing products from a powder composition of aluminum, silicon and magnesium by selective laser melting.
{"title":"Synthesis of a three-component aluminum-based alloy by selective laser melting","authors":"N. Saprykina, V. Chebodaeva, A. Saprykin, Y. Sharkeev, E. Ibragimov, Taisiya Guseva","doi":"10.17212/1994-6309-2022-24.4-151-164","DOIUrl":"https://doi.org/10.17212/1994-6309-2022-24.4-151-164","url":null,"abstract":"Introduction. The technology of selective laser melting is one of the key technologies in Industry 4.0, which allows manufacturing products of any complex geometric shape, reducing significantly the amount of material used, reducing the lead time and obtaining a new alloy from elementary powders in the melting process. To understand the process of alloy formation under laser exposure, it is necessary to know the initial data of powders, which significantly affect the quality of the products obtained. The purpose of this study is to determine the requirements for the structural-phase state, elemental composition of aluminum, silicon and magnesium powders and further preparation of Al-Si-Mg (Al — 91 wt.%, Si — 8 wt.%, Mg — 1 wt.%) powder mixture for laser synthesis. The initial powders of aluminum PA-4 (GOST 6058-73), silicon (GOST 2169-69) and magnesium MPF-4 (GOST 6001-79) and powder composition Al-Si-Mg are studied using X-ray diffraction and X-ray phase analysis. The shape and sizes of particles are determined by the studies of raster electronic images. By the method of selective laser melting, samples are obtained from a powder composition under constant and pulsed laser exposure. The composition is prepared by mixing powders in a globe mill. Results and discussion. It is shown that the initial powders of aluminum, silicon and magnesium are single-phase. Particles with a size of 20–64 µm, recommended for selective laser melting, are used to obtain a powder composition. By mixing the powders for one hour, spherical particles are obtained, which is preferable for laser melting. The results of grinding the samples after laser melting showed that the samples obtained under constant laser exposure at the following mode parameters: P = 80 W, V = 300 mm/s, s = 90 μm, h = 25 μm have the greatest mechanical strength. Conclusions. The described study shows the possibility of synthesizing products from a powder composition of aluminum, silicon and magnesium by selective laser melting.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46327688","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 : 2022-12-15DOI: 10.17212/1994-6309-2022-24.4-206-218
A. Eroshenko, E. Legostaeva, I. Glukhov, P. Uvarkin, A. Tolmachev, N. Luginin, Vladimir Bataev, I. Ivanov, Y. Sharkeev
Introduction. The interest of modern medical materials science is focused on the development of beta-alloys of ternary systems (TNZ) based on titanium, niobium and zirconium with the low Young’s modulus, which is comparable with the elastic modulus of the bone. A wide application of the above alloys in medicine is limited by its insufficiently high strength properties, such as yield strength, ultimate strength, fatigue strength, fatigue life, etc. The formation of bulk ultrafine-grained structure in the alloys via deformation processing, including severe plastic deformation, ensures a considerable increase in the mechanical properties of alloys without toxic alloying elements. The aim of the work is to analyze the influence of deformation (multipass rolling and abc-pressing in combination with rolling) on the microstructure and mechanical properties of the alloy of the Ti-Nb-Zr system. The research methods. The Ti-42Nb-7Zr alloy cast blanks were made from pure titanium, niobium, and zirconium iodides by arc melting with a tungsten electrode in the protective argon atmosphere. It is shown that the cast blanks obtained have a high degree of uniformity in the distribution of niobium and zirconium alloying elements. To form an ultrafine-grained (UFG) structure, the cast blanks were subjected to deformation according to two schemes: 1) multipass rolling and 2) a combined method of severe plastic deformation, consisting in abc-pressing and subsequent multipass groove rolling. Results and discussion. As a result of deformation processing by rolling, an ultrafine-grained (UFG) structure is formed, which is represented by non-equiaxed -subgrains with cross-sectional dimensions 0.2…0.8 µm and length 0.2…0.7 µm, dispersion strengthened nanosized ω-phase, as well as subgrains of the -phase. Application of combined severe plastic deformation has promoted formation of a more dispersed UFG (+ω)-structure with an average size of structural elements equal to 0.3 μm. The UFG structure formed as a result of two-stage SPD has provided a high level of mechanical properties: yield strength – 480 MPa, ultimate strength – 1.100 MPa, microhardness – 2.800 MPa, with a low modulus of elasticity equal to 36 GPa.
{"title":"Effect of deformation processing on microstructure and mechanical properties of Ti-42Nb-7Zr alloy","authors":"A. Eroshenko, E. Legostaeva, I. Glukhov, P. Uvarkin, A. Tolmachev, N. Luginin, Vladimir Bataev, I. Ivanov, Y. Sharkeev","doi":"10.17212/1994-6309-2022-24.4-206-218","DOIUrl":"https://doi.org/10.17212/1994-6309-2022-24.4-206-218","url":null,"abstract":"Introduction. The interest of modern medical materials science is focused on the development of beta-alloys of ternary systems (TNZ) based on titanium, niobium and zirconium with the low Young’s modulus, which is comparable with the elastic modulus of the bone. A wide application of the above alloys in medicine is limited by its insufficiently high strength properties, such as yield strength, ultimate strength, fatigue strength, fatigue life, etc. The formation of bulk ultrafine-grained structure in the alloys via deformation processing, including severe plastic deformation, ensures a considerable increase in the mechanical properties of alloys without toxic alloying elements. The aim of the work is to analyze the influence of deformation (multipass rolling and abc-pressing in combination with rolling) on the microstructure and mechanical properties of the alloy of the Ti-Nb-Zr system. The research methods. The Ti-42Nb-7Zr alloy cast blanks were made from pure titanium, niobium, and zirconium iodides by arc melting with a tungsten electrode in the protective argon atmosphere. It is shown that the cast blanks obtained have a high degree of uniformity in the distribution of niobium and zirconium alloying elements. To form an ultrafine-grained (UFG) structure, the cast blanks were subjected to deformation according to two schemes: 1) multipass rolling and 2) a combined method of severe plastic deformation, consisting in abc-pressing and subsequent multipass groove rolling. Results and discussion. As a result of deformation processing by rolling, an ultrafine-grained (UFG) structure is formed, which is represented by non-equiaxed -subgrains with cross-sectional dimensions 0.2…0.8 µm and length 0.2…0.7 µm, dispersion strengthened nanosized ω-phase, as well as subgrains of the -phase. Application of combined severe plastic deformation has promoted formation of a more dispersed UFG (+ω)-structure with an average size of structural elements equal to 0.3 μm. The UFG structure formed as a result of two-stage SPD has provided a high level of mechanical properties: yield strength – 480 MPa, ultimate strength – 1.100 MPa, microhardness – 2.800 MPa, with a low modulus of elasticity equal to 36 GPa.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46609724","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 : 2022-12-15DOI: 10.17212/1994-6309-2022-24.4-138-150
N. Pugacheva, Yu. V. Nikolin, T. Bykova, L. Goruleva
Introduction. Plasma spraying is one of the modern and effective methods for coatings application for various purposes and compositions. With the help of thermal plasma flows, it is possible to spray almost any powder materials (ceramic, metal, metal-ceramic). Plasma spraying of multilayer protective coatings can be successfully used to increase the durability of pierced mandrels, which are the main tool in the production of hollow billets. The purpose of this work is to study the chemical composition, structure, and microhardness of multilayer high-temperature coatings of two different compositions deposited by plasma spraying, which are supposed to be used to increase the durability of pierced mandrels. Materials and research methods. The deposition of multilayer coatings of two compositions was carried out on a plasma-powder spraying unit with contact excitation of an arc discharge UPN-60KM TSP2017. Coatings were obtained by sequential deposition of three layers with different powder compositions. After deposition of all three coating layers, oxidative annealing was carried out at a temperature of 900°C to form a dense scale layer of FeO + Fe2O3 + Fe3O4 on the surface. The chemical composition of the coatings was studied by X-ray microanalysis using a TESCAN scanning electron microscope with an OXFORD attachment. The microstructure of the coatings was studied using a NEOPHOT metallographic microscope. Phase X-ray diffraction analysis was performed on a SHIMADZU diffractometer in Kα chromium radiation. Microhardness was measured on a LEICA hardness tester at a load of 50 g. Results and discussion. The nature of the distribution of chemical elements over the thickness of the coating, consisting of four layers, is established: an inner metal layer that provides protection against high-temperature corrosion; a transitional metal layer designed to equalize the thermal properties between the layers; α-Fe metal oxide layer and iron oxides and external thermal barrier oxide layer FeO + Fe2O3 + Fe3O4. Coatings are characterized by a non-uniform distribution of structural components and microhardness over its thickness. The microhardness of the inner layer reaches 1,400 HV0.05, the transition layer is 800 HV0.05, and the metal oxide layer is 300 HV0.05.
{"title":"Chemical composition, structure and microhardness of multilayer high-temperature coatings","authors":"N. Pugacheva, Yu. V. Nikolin, T. Bykova, L. Goruleva","doi":"10.17212/1994-6309-2022-24.4-138-150","DOIUrl":"https://doi.org/10.17212/1994-6309-2022-24.4-138-150","url":null,"abstract":"Introduction. Plasma spraying is one of the modern and effective methods for coatings application for various purposes and compositions. With the help of thermal plasma flows, it is possible to spray almost any powder materials (ceramic, metal, metal-ceramic). Plasma spraying of multilayer protective coatings can be successfully used to increase the durability of pierced mandrels, which are the main tool in the production of hollow billets. The purpose of this work is to study the chemical composition, structure, and microhardness of multilayer high-temperature coatings of two different compositions deposited by plasma spraying, which are supposed to be used to increase the durability of pierced mandrels. Materials and research methods. The deposition of multilayer coatings of two compositions was carried out on a plasma-powder spraying unit with contact excitation of an arc discharge UPN-60KM TSP2017. Coatings were obtained by sequential deposition of three layers with different powder compositions. After deposition of all three coating layers, oxidative annealing was carried out at a temperature of 900°C to form a dense scale layer of FeO + Fe2O3 + Fe3O4 on the surface. The chemical composition of the coatings was studied by X-ray microanalysis using a TESCAN scanning electron microscope with an OXFORD attachment. The microstructure of the coatings was studied using a NEOPHOT metallographic microscope. Phase X-ray diffraction analysis was performed on a SHIMADZU diffractometer in Kα chromium radiation. Microhardness was measured on a LEICA hardness tester at a load of 50 g. Results and discussion. The nature of the distribution of chemical elements over the thickness of the coating, consisting of four layers, is established: an inner metal layer that provides protection against high-temperature corrosion; a transitional metal layer designed to equalize the thermal properties between the layers; α-Fe metal oxide layer and iron oxides and external thermal barrier oxide layer FeO + Fe2O3 + Fe3O4. Coatings are characterized by a non-uniform distribution of structural components and microhardness over its thickness. The microhardness of the inner layer reaches 1,400 HV0.05, the transition layer is 800 HV0.05, and the metal oxide layer is 300 HV0.05.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42930032","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 : 2022-12-15DOI: 10.17212/1994-6309-2022-24.4-192-205
E. Korosteleva, I. Nikolaev, V. Korzhova
Introduction. Manufacturing processes, to one degree or another, are associated with the metal waste production in the form of metal chips. The development of technologies for recycling of waste from mechanical facilities is a popular solution both from the resource saving and from an environmental points of view. Among many traditional approaches to the problem of recycling metal chips, the most interesting may be the method of using chips as one of the components in a powder material. The aim of this work is to analyze the possibility of using metalworking wastes from steel 45 (metal chips) in powder compositions based on titanium and aluminum not only as a source of iron, but also as a possible source of Fe2O3 oxide. Attention to the oxide was paid in terms of initiating reduction reactions in the powder mixture based on titanium and aluminum with the formation of the Al2O3 oxide phase to obtain a metal matrix composite. Research methods: steel chips after processing workpieces from steel 45 were additionally oxidized in water and crushed in a vibrating mill to an average particle size of 300 μm for use in powder compositions with titanium and aluminum powders. Grinded and oxidized chips were mixed with titanium and aluminum powders in various proportions in order to study its interaction with these powder components. The obtained mixtures were pressed in the form of cylindrical samples and sintered in a vacuum furnace at a temperature of 1,000 °C. The phase composition and microstructure were studied using an XRD-6000 X-ray diffractometer with CuKα – radiation and an AXIOVERT-200MAT optical microscope. Results and discussions. It is shown that after milling without coolant, steel 45 chips did not accumulate a noticeable amount of iron oxides, which required additional oxidizing procedures. The interaction of grinded oxidized chips with the components of powder mixtures is considered, and its effect on volumetric changes in compacts and structure formation of metal-matrix composites is shown. The results of optical metallography and X-ray diffraction analysis (XRD) of sintered powder compositions using oxidized ground chips of steel 45 made it possible to evaluate the ongoing processes of structure formation depending on the combination of interacting components, its mutual influence, and the prospects for obtaining composites with a dispersed oxide phase.
{"title":"Features of the structure formation of sintered powder materials using waste metal processing of steel workpieces","authors":"E. Korosteleva, I. Nikolaev, V. Korzhova","doi":"10.17212/1994-6309-2022-24.4-192-205","DOIUrl":"https://doi.org/10.17212/1994-6309-2022-24.4-192-205","url":null,"abstract":"Introduction. Manufacturing processes, to one degree or another, are associated with the metal waste production in the form of metal chips. The development of technologies for recycling of waste from mechanical facilities is a popular solution both from the resource saving and from an environmental points of view. Among many traditional approaches to the problem of recycling metal chips, the most interesting may be the method of using chips as one of the components in a powder material. The aim of this work is to analyze the possibility of using metalworking wastes from steel 45 (metal chips) in powder compositions based on titanium and aluminum not only as a source of iron, but also as a possible source of Fe2O3 oxide. Attention to the oxide was paid in terms of initiating reduction reactions in the powder mixture based on titanium and aluminum with the formation of the Al2O3 oxide phase to obtain a metal matrix composite. Research methods: steel chips after processing workpieces from steel 45 were additionally oxidized in water and crushed in a vibrating mill to an average particle size of 300 μm for use in powder compositions with titanium and aluminum powders. Grinded and oxidized chips were mixed with titanium and aluminum powders in various proportions in order to study its interaction with these powder components. The obtained mixtures were pressed in the form of cylindrical samples and sintered in a vacuum furnace at a temperature of 1,000 °C. The phase composition and microstructure were studied using an XRD-6000 X-ray diffractometer with CuKα – radiation and an AXIOVERT-200MAT optical microscope. Results and discussions. It is shown that after milling without coolant, steel 45 chips did not accumulate a noticeable amount of iron oxides, which required additional oxidizing procedures. The interaction of grinded oxidized chips with the components of powder mixtures is considered, and its effect on volumetric changes in compacts and structure formation of metal-matrix composites is shown. The results of optical metallography and X-ray diffraction analysis (XRD) of sintered powder compositions using oxidized ground chips of steel 45 made it possible to evaluate the ongoing processes of structure formation depending on the combination of interacting components, its mutual influence, and the prospects for obtaining composites with a dispersed oxide phase.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":"1 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67545211","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 : 2022-12-15DOI: 10.17212/1994-6309-2022-24.4-219-242
O. Kutkin, I. Bataev, G. Dovzhenko, Z. Bataeva
The paper contains a review of research related to the use of synchrotron radiation computed laminography in the study of the structure features of metal alloys subjected to various methods of external action. Introduction. The important role of X-rays in the field of materials research is discussed. The capabilities of standard X-ray devices equipped with X-ray tubes and modern synchrotron radiation (SR) sources with unique parameters are compared. Methods for studying flat samples. Tomography and synchrotron laminography. An informative method based on the use of synchrotron X-rays is synchrotron radiation computed tomography (SRCT), which allows obtaining cross-section images of objects by processing multiple absorption radiographs. A brief classification of five generations of tomographs is presented. The problems encountered in obtaining data from non-compact (non-isometric) samples are avoided by using the method of synchrotron radiation computed laminography (SRCL), which combines the principles of laminography with the advantages of synchrotron imaging. Currently the method is used for non-destructive testing of non-isometric objects by a number of synchrotron radiation sources (ESRF, ANKA, Spring-8). Resolution of synchrotron radiation computed laminography. The use of monochromatic radiation in realization of computed laminography method is a factor, which provides high spatial resolution down to micron and submicron scale. An equally important factor is related to the characteristics of the detector. Images with a resolution of ~100 nm were obtained using nanolaminography. Comparison of laminography and tomography methods. Augmented laminography. Augmented laminography allows improving image quality by augmenting the Fourier space analyzed by laminography with information obtained from lower resolution CT. Reconstruction performed using Augmented laminography is characterized by the absence of significant artifacts and high resolution. Implementation of the laminography method. The angle of inclination of the rotary axis θ (SRCL method) is related to the geometry of samples and is determined experimentally in each case. In order to achieve the necessary resolution, the value θ should provide an optimal average value of the intensity of the passed radiation. The energy of X-rays is calculated on the basis of material characteristics. To reconstruct images of the objects, software complexes that implement the filtered back projection method based on the Radon transform are used. Examples of laminography application for analysis of metal alloys samples. The laminography method can be used for in-situ investigations allowing real time monitoring of processes occurring under different conditions of external action, e.g. during plastic deformation of metal plates. Data on formation of pore-type defects in the process of loading of metal workpieces are interesting. Numerous examples of post-mortem studies of metal alloys for various purposes
{"title":"The study of characteristics of the structure of metallic alloys using synchrotron radiation computed laminography (Research Review)","authors":"O. Kutkin, I. Bataev, G. Dovzhenko, Z. Bataeva","doi":"10.17212/1994-6309-2022-24.4-219-242","DOIUrl":"https://doi.org/10.17212/1994-6309-2022-24.4-219-242","url":null,"abstract":"The paper contains a review of research related to the use of synchrotron radiation computed laminography in the study of the structure features of metal alloys subjected to various methods of external action. Introduction. The important role of X-rays in the field of materials research is discussed. The capabilities of standard X-ray devices equipped with X-ray tubes and modern synchrotron radiation (SR) sources with unique parameters are compared. Methods for studying flat samples. Tomography and synchrotron laminography. An informative method based on the use of synchrotron X-rays is synchrotron radiation computed tomography (SRCT), which allows obtaining cross-section images of objects by processing multiple absorption radiographs. A brief classification of five generations of tomographs is presented. The problems encountered in obtaining data from non-compact (non-isometric) samples are avoided by using the method of synchrotron radiation computed laminography (SRCL), which combines the principles of laminography with the advantages of synchrotron imaging. Currently the method is used for non-destructive testing of non-isometric objects by a number of synchrotron radiation sources (ESRF, ANKA, Spring-8). Resolution of synchrotron radiation computed laminography. The use of monochromatic radiation in realization of computed laminography method is a factor, which provides high spatial resolution down to micron and submicron scale. An equally important factor is related to the characteristics of the detector. Images with a resolution of ~100 nm were obtained using nanolaminography. Comparison of laminography and tomography methods. Augmented laminography. Augmented laminography allows improving image quality by augmenting the Fourier space analyzed by laminography with information obtained from lower resolution CT. Reconstruction performed using Augmented laminography is characterized by the absence of significant artifacts and high resolution. Implementation of the laminography method. The angle of inclination of the rotary axis θ (SRCL method) is related to the geometry of samples and is determined experimentally in each case. In order to achieve the necessary resolution, the value θ should provide an optimal average value of the intensity of the passed radiation. The energy of X-rays is calculated on the basis of material characteristics. To reconstruct images of the objects, software complexes that implement the filtered back projection method based on the Radon transform are used. Examples of laminography application for analysis of metal alloys samples. The laminography method can be used for in-situ investigations allowing real time monitoring of processes occurring under different conditions of external action, e.g. during plastic deformation of metal plates. Data on formation of pore-type defects in the process of loading of metal workpieces are interesting. Numerous examples of post-mortem studies of metal alloys for various purposes ","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42005849","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 : 2022-12-15DOI: 10.17212/1994-6309-2022-24.4-127-137
A. Burkov, V. Krutikova
Introduction. Metal-ceramic coatings based on titanium silicide are promising for protecting stainless steel AISI 304 from wear, corrosion and high-temperature oxidation. Purpose of the work: to investigate the stainless steel AISI 304 surface layer structure after electrospark deposition in a mixture of titanium granules with silicon powder, and to study oxidation resistance, corrosion resistance and tribotechnical properties of the obtained coatings. Research methodology. Fe-Ti-Si coatings on the stainless steel AISI 304 samples were obtained by electrospark machining with a non-localized electrode consisting of titanium granules and 2.6-6 vol.% mixture of titanium and crystalline silicon powders. Results and discussion: it is shown that a stable positive gain of the cathode is observed when the proportion of silicon in the powder mixture does not exceed 32 vol.%. The phase composition of the coatings includes: a solid solution of chromium in iron, titanium silicide Ti5Si3, titanium and silicon, which is confirmed by the energy dispersion analysis data. The microhardness of Fe-Ti-Si coatings ranges from 10.05 to 12.86 GPa, which is 5-6 times higher than that of uncoated steel AISI 304. The coefficient of friction of the coatings is about 20% lower compared to steel AISI 304 and hovers around 0.71-0.73. Wear tests in dry sliding mode show that Fe-Ti-Si coatings can increase the wear resistance of steel AISI 304 up to 6 times. The oxidation resistance of the coatings at a temperature of 900 ̊С is 7-12 times higher as compared to steel AISI 304. The conducted studies have shown that new electrospark Fe-Ti-Si coatings can increase corrosion resistance, oxidation resistance, microhardness, as well as reduce the coefficient of friction and wear rate of the stainless steel AISI 304 surface.
{"title":"Deposition of titanium silicide on stainless steel AISI 304 surface","authors":"A. Burkov, V. Krutikova","doi":"10.17212/1994-6309-2022-24.4-127-137","DOIUrl":"https://doi.org/10.17212/1994-6309-2022-24.4-127-137","url":null,"abstract":"Introduction. Metal-ceramic coatings based on titanium silicide are promising for protecting stainless steel AISI 304 from wear, corrosion and high-temperature oxidation. Purpose of the work: to investigate the stainless steel AISI 304 surface layer structure after electrospark deposition in a mixture of titanium granules with silicon powder, and to study oxidation resistance, corrosion resistance and tribotechnical properties of the obtained coatings. Research methodology. Fe-Ti-Si coatings on the stainless steel AISI 304 samples were obtained by electrospark machining with a non-localized electrode consisting of titanium granules and 2.6-6 vol.% mixture of titanium and crystalline silicon powders. Results and discussion: it is shown that a stable positive gain of the cathode is observed when the proportion of silicon in the powder mixture does not exceed 32 vol.%. The phase composition of the coatings includes: a solid solution of chromium in iron, titanium silicide Ti5Si3, titanium and silicon, which is confirmed by the energy dispersion analysis data. The microhardness of Fe-Ti-Si coatings ranges from 10.05 to 12.86 GPa, which is 5-6 times higher than that of uncoated steel AISI 304. The coefficient of friction of the coatings is about 20% lower compared to steel AISI 304 and hovers around 0.71-0.73. Wear tests in dry sliding mode show that Fe-Ti-Si coatings can increase the wear resistance of steel AISI 304 up to 6 times. The oxidation resistance of the coatings at a temperature of 900 ̊С is 7-12 times higher as compared to steel AISI 304. The conducted studies have shown that new electrospark Fe-Ti-Si coatings can increase corrosion resistance, oxidation resistance, microhardness, as well as reduce the coefficient of friction and wear rate of the stainless steel AISI 304 surface.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46816068","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 : 2022-12-15DOI: 10.17212/1994-6309-2022-24.4-181-191
I. Ivanov, A. Yurgin, Igor Nasennik, K. Kuper
Introduction. All plastically deformed alloys are characterized by crystal defects that increase the internal energy of the system. These defects also result in residual stresses that have a complex effect on the material properties. Macrostresses are often the most critical and can lead to warpage, reduced corrosion resistance, and changes in material strength characteristics. The purpose of this work is to assess the residual stresses of the primitive cubic phase of high entropy alloys Al0.6CoCrFeNi and AlCoCrFeNi. Research methods. The crystal structure of the alloys is studied using the method of X-ray diffraction analysis. Experiments on X-ray diffraction analysis were carried out at the Siberian Center for Synchrotron and Terahertz Radiation on a VEPP-4 (Novosibirsk, INF SB RAS, 5-A line «X-ray microscopy and tomography»). Studies using synchrotron radiation were carried out in the transmission mode. The evaluation of the residual macrostresses of the crystalline phases of the alloys was based on the analysis of the change in the shape of the diffraction rings with a change in the azimuth angle (). Materials. The objects of research are ingots of high-entropy alloys Al0.6CoCrFeNi and AlCoCrFeNi. The ingots were obtained from pure metals by argon arc melting with cooling on a copper plate. To conduct further studies, cylindrical samples are cut from the ingots, which were subjected to plastic deformation according to the uniaxial compression scheme. Results and discussion. The obtained results indicate that the Al0.6CoCrFeNi alloy is characterized by higher macrostresses than the AlCoCrFeNi alloy. The residual deformation of the B2 phase lattice of AlCoCrFeNi alloy along the direction [100] is 2.5% at an external load of 2,500 MPa. The distortion value of the lattice of this phase for the alloy Al0.6CoCrFeNi is equal to 5.5% under similar external conditions. In addition, the plastic deformation of the Al0.6CoCrFeNi HEA did not lead to its destruction. This allows concluding that the increased ductility of this alloy is associated not only with the presence of a phase with a FCC lattice, but also with an increased compliance of the phase with a primitive lattice.
{"title":"Residual stress estimation in crystalline phases of high-entropy alloys of the AlxCoCrFeNi system","authors":"I. Ivanov, A. Yurgin, Igor Nasennik, K. Kuper","doi":"10.17212/1994-6309-2022-24.4-181-191","DOIUrl":"https://doi.org/10.17212/1994-6309-2022-24.4-181-191","url":null,"abstract":"Introduction. All plastically deformed alloys are characterized by crystal defects that increase the internal energy of the system. These defects also result in residual stresses that have a complex effect on the material properties. Macrostresses are often the most critical and can lead to warpage, reduced corrosion resistance, and changes in material strength characteristics. The purpose of this work is to assess the residual stresses of the primitive cubic phase of high entropy alloys Al0.6CoCrFeNi and AlCoCrFeNi. Research methods. The crystal structure of the alloys is studied using the method of X-ray diffraction analysis. Experiments on X-ray diffraction analysis were carried out at the Siberian Center for Synchrotron and Terahertz Radiation on a VEPP-4 (Novosibirsk, INF SB RAS, 5-A line «X-ray microscopy and tomography»). Studies using synchrotron radiation were carried out in the transmission mode. The evaluation of the residual macrostresses of the crystalline phases of the alloys was based on the analysis of the change in the shape of the diffraction rings with a change in the azimuth angle (). Materials. The objects of research are ingots of high-entropy alloys Al0.6CoCrFeNi and AlCoCrFeNi. The ingots were obtained from pure metals by argon arc melting with cooling on a copper plate. To conduct further studies, cylindrical samples are cut from the ingots, which were subjected to plastic deformation according to the uniaxial compression scheme. Results and discussion. The obtained results indicate that the Al0.6CoCrFeNi alloy is characterized by higher macrostresses than the AlCoCrFeNi alloy. The residual deformation of the B2 phase lattice of AlCoCrFeNi alloy along the direction [100] is 2.5% at an external load of 2,500 MPa. The distortion value of the lattice of this phase for the alloy Al0.6CoCrFeNi is equal to 5.5% under similar external conditions. In addition, the plastic deformation of the Al0.6CoCrFeNi HEA did not lead to its destruction. This allows concluding that the increased ductility of this alloy is associated not only with the presence of a phase with a FCC lattice, but also with an increased compliance of the phase with a primitive lattice.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42453547","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 : 2022-12-15DOI: 10.17212/1994-6309-2022-24.4-165-180
D. Gabets, A. Markov, Mikhail Guryev, E. Pismenny, A. Nasyrova
Introduction. An approach based on the complex modification of cast irons makes it possible to improve its mechanical properties by changing the structure of the metal matrix, as well as the shape of graphite and its distribution. The aim of this work is to study the influence of alloying elements on the structure and mechanical properties of gray cast irons obtained for operation under friction wear conditions. Research methods. The paper describes the process of obtaining complex modified gray cast irons. Fractographic investigation of dynamically destroyed samples is carried out. Structure’s features of SCh35, ChMN-35M and SChKM-45 gray cast irons are studied. Tribological testing under sliding friction conditions is carried out. Results and its discussion. It is established that the complex modification of SCh35 gray cast iron with molybdenum, nickel and vanadium makes it possible to increase its hardness to 295 HB and tensile strength to 470-505 MPa. Alloying with nickel (0.4-0.7 wt.%), molybdenum (0.4-0.7 wt.%) and vanadium (0.2-0.4 wt.%) leads to a decrease in the interlamellar distance of perlite by 2 times, as well as to the metal matrix grain refining. The length of graphite lamellas of modified cast irons is reduced by 3-5 times. An additional effect on the tensile strength of cast iron is due to the alloying of ferrite with molybdenum and vanadium, which is fallen out along the boundaries of graphite inclusions. Alloying of ferrite with molybdenum and vanadium increases the level of its microhardness by 1.4 times in comparison with the α-phase of SCh35 serial cast iron. The results of tribotechnical tests of the designed materials are presented. Conclusions. It is established that the wear of specimens made of SChKM-45 cast iron is approximately 20-30% lower compared to cast iron SCh35 cast iron and 10-15% lower compared to ChMN-35M cast iron. Fractographic studies show that complex alloying with molybdenum, vanadium and nickel, contributing to the refining of pearlite colonies, leads to a decrease of the size of the cleavage facets.
{"title":"The effect of complex modification on the structure and properties of gray cast iron for tribotechnical application","authors":"D. Gabets, A. Markov, Mikhail Guryev, E. Pismenny, A. Nasyrova","doi":"10.17212/1994-6309-2022-24.4-165-180","DOIUrl":"https://doi.org/10.17212/1994-6309-2022-24.4-165-180","url":null,"abstract":"Introduction. An approach based on the complex modification of cast irons makes it possible to improve its mechanical properties by changing the structure of the metal matrix, as well as the shape of graphite and its distribution. The aim of this work is to study the influence of alloying elements on the structure and mechanical properties of gray cast irons obtained for operation under friction wear conditions. Research methods. The paper describes the process of obtaining complex modified gray cast irons. Fractographic investigation of dynamically destroyed samples is carried out. Structure’s features of SCh35, ChMN-35M and SChKM-45 gray cast irons are studied. Tribological testing under sliding friction conditions is carried out. Results and its discussion. It is established that the complex modification of SCh35 gray cast iron with molybdenum, nickel and vanadium makes it possible to increase its hardness to 295 HB and tensile strength to 470-505 MPa. Alloying with nickel (0.4-0.7 wt.%), molybdenum (0.4-0.7 wt.%) and vanadium (0.2-0.4 wt.%) leads to a decrease in the interlamellar distance of perlite by 2 times, as well as to the metal matrix grain refining. The length of graphite lamellas of modified cast irons is reduced by 3-5 times. An additional effect on the tensile strength of cast iron is due to the alloying of ferrite with molybdenum and vanadium, which is fallen out along the boundaries of graphite inclusions. Alloying of ferrite with molybdenum and vanadium increases the level of its microhardness by 1.4 times in comparison with the α-phase of SCh35 serial cast iron. The results of tribotechnical tests of the designed materials are presented. Conclusions. It is established that the wear of specimens made of SChKM-45 cast iron is approximately 20-30% lower compared to cast iron SCh35 cast iron and 10-15% lower compared to ChMN-35M cast iron. Fractographic studies show that complex alloying with molybdenum, vanadium and nickel, contributing to the refining of pearlite colonies, leads to a decrease of the size of the cleavage facets.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42887292","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 : 2022-12-15DOI: 10.17212/1994-6309-2022-24.4-64-83
D. Ardashev, Alexander Zhukov
Introduction. Modern mechanical engineering is closely connected with digital production management technologies, for which an important aspect is the collection of reliable information about the current state of the systems. Acoustic methods of current control of the tool cutting ability possess significant potential due to the possibility of continuously obtaining up-to-date data on the parameters of machining process. Profile grinding is one of the widespread methods of machining surfaces of complex configuration. The high importance of this method lies in the high degree of responsibility of shaped parts obtained with it. The wear parameter of profiled grinding wheels needs current control to the same extent as other types of cutting tools. At the same time, acoustic methods of research have not found wide application in relation to profile grinding. In view of this, the present work is aimed at studying the influence of the tool wear rate on the acoustic characteristics of grinding when using grinding wheels of different profiles. Purpose of work is to determine the acoustic parameters of profile grinding with application of planar grinding scheme as it wears out in comparison with analogical process with application of straight profile grinding wheel. As the basic methods of research an experiment is used to study the acoustic phenomena accompanying grinding with application of wheels of different profile. An analysis of the acoustic signal of grinding is carried out, as well as an analysis of the spectrum of its frequency composition. The frequencies of natural vibrations of grinding wheels of different profiles are investigated, its sound index is determined as a criterion for evaluating its characteristics. Acoustic characteristics of the grinding process with the use of grinding wheels of different profiles are compared. Regression analysis of acoustic data obtained as a result of the experiment is also used. Results and discussion. Spectrograms of frequencies of natural vibrations of the wheels under research, as well as a number of spectrograms of the acoustic signal accompanying the processing process for various technological conditions are received. As a result of comparing the obtained spectrograms, the informative frequencies of the grinding processes are determined. Mathematical models of sound level dependence on the value of periodic vertical feed St at depth t and processing time T are developed. It is established that the value of periodic vertical feed St at depth t has a greater influence on the acoustic index in comparison with the machining duration T. Practical significance and prospects of the results of the work lies in the possibility of increasing the efficiency of profile grinding processes due to the rational use of the tool availability.
{"title":"Investigation of the relationship between the cutting ability of the tool and the acoustic signal parameters during profile grinding","authors":"D. Ardashev, Alexander Zhukov","doi":"10.17212/1994-6309-2022-24.4-64-83","DOIUrl":"https://doi.org/10.17212/1994-6309-2022-24.4-64-83","url":null,"abstract":"Introduction. Modern mechanical engineering is closely connected with digital production management technologies, for which an important aspect is the collection of reliable information about the current state of the systems. Acoustic methods of current control of the tool cutting ability possess significant potential due to the possibility of continuously obtaining up-to-date data on the parameters of machining process. Profile grinding is one of the widespread methods of machining surfaces of complex configuration. The high importance of this method lies in the high degree of responsibility of shaped parts obtained with it. The wear parameter of profiled grinding wheels needs current control to the same extent as other types of cutting tools. At the same time, acoustic methods of research have not found wide application in relation to profile grinding. In view of this, the present work is aimed at studying the influence of the tool wear rate on the acoustic characteristics of grinding when using grinding wheels of different profiles. Purpose of work is to determine the acoustic parameters of profile grinding with application of planar grinding scheme as it wears out in comparison with analogical process with application of straight profile grinding wheel. As the basic methods of research an experiment is used to study the acoustic phenomena accompanying grinding with application of wheels of different profile. An analysis of the acoustic signal of grinding is carried out, as well as an analysis of the spectrum of its frequency composition. The frequencies of natural vibrations of grinding wheels of different profiles are investigated, its sound index is determined as a criterion for evaluating its characteristics. Acoustic characteristics of the grinding process with the use of grinding wheels of different profiles are compared. Regression analysis of acoustic data obtained as a result of the experiment is also used. Results and discussion. Spectrograms of frequencies of natural vibrations of the wheels under research, as well as a number of spectrograms of the acoustic signal accompanying the processing process for various technological conditions are received. As a result of comparing the obtained spectrograms, the informative frequencies of the grinding processes are determined. Mathematical models of sound level dependence on the value of periodic vertical feed St at depth t and processing time T are developed. It is established that the value of periodic vertical feed St at depth t has a greater influence on the acoustic index in comparison with the machining duration T. Practical significance and prospects of the results of the work lies in the possibility of increasing the efficiency of profile grinding processes due to the rational use of the tool availability.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41952045","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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