One of the cheapest methods of extracting gold is heap leaching. However, the recovery of gold by this method is relatively low, compared with cyanidation of the crushed material, so the search for the ways to intensify leaching and increase gold recovery is an urgent task. Investigations on heap leaching of gold from the gold-bearing ore of the Sari Gunay deposit were conducted using a promising reagent sodium acetate to intensify the heap leaching process. The results of assay-gravimetric, chemical, mineralogical and granulometric analyses of oxidized ore are presented. The average gold content in the ore was 2.90 g/t. According to the electron probe analysis, gold in the ore is present in the form of fine (micron) inclusions in minerals and ore rocks. Comparative studies on heap leaching of gold from the crushed ore with a grain size of –20 + 0 mm with the addition of sodium acetate and without that were carried out. The degree of gold recovery with sodium acetate at a flow rate of 0.5 kg/t was 58.74%, that without sodium acetate was 54.69%, i.e. the addition of the reagent provides an increase in recovery of more than 4%. Leaching with the addition of the reagent also reduces sodium cyanide consumption from 0.65 to 0.59 kg/t. The research results have shown that sodium acetate can be used to intensify the process of heap leaching of gold when the ore size is –20+0 mm.
{"title":"Studies on heap leaching of gold with the addition of sodium acetate as an intensifying reagent","authors":"Y. Yessengarayev, B. Baimbetov, B. Surimbayev","doi":"10.17580/NFM.2020.02.04","DOIUrl":"https://doi.org/10.17580/NFM.2020.02.04","url":null,"abstract":"One of the cheapest methods of extracting gold is heap leaching. However, the recovery of gold by this method is relatively low, compared with cyanidation of the crushed material, so the search for the ways to intensify leaching and increase gold recovery is an urgent task. Investigations on heap leaching of gold from the gold-bearing ore of the Sari Gunay deposit were conducted using a promising reagent sodium acetate to intensify the heap leaching process. The results of assay-gravimetric, chemical, mineralogical and granulometric analyses of oxidized ore are presented. The average gold content in the ore was 2.90 g/t. According to the electron probe analysis, gold in the ore is present in the form of fine (micron) inclusions in minerals and ore rocks. Comparative studies on heap leaching of gold from the crushed ore with a grain size of –20 + 0 mm with the addition of sodium acetate and without that were carried out. The degree of gold recovery with sodium acetate at a flow rate of 0.5 kg/t was 58.74%, that without sodium acetate was 54.69%, i.e. the addition of the reagent provides an increase in recovery of more than 4%. Leaching with the addition of the reagent also reduces sodium cyanide consumption from 0.65 to 0.59 kg/t. The research results have shown that sodium acetate can be used to intensify the process of heap leaching of gold when the ore size is –20+0 mm.","PeriodicalId":19653,"journal":{"name":"Nonferrous Metals","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2020-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44391548","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}
The article presents the results of a study of the factors affecting the efficiency of the copper-molybdenum ore flotation. The objective of this work was to substantiate and develop a reagent mode for flotation of the Erdenetiyn-Ovoo porphyry copper ores, which makes possible extracting main copper and molybdenum minerals into corresponding concentrates more fully and selectively. It is shown that the use of a DC-80 (2-methyl-3-butin-2-ol) flotation reagent in assosiation with the main base mode reagents — an AERO MX-5152 (a mixture of allyl ethers of xanthogenic acids with n-butyloxycarbonyl-O-n-butylthionocarbamate) combined nonionized collector, a BK-901B (a composition of dialkyldithiophosphate and O,N-dialkyldithiocarbamate) blending ionized collector; diesel fuel; a MIBC (methyl isobutyl carbinol) frother; sodium sulphide Na2S as a modifier and lime СаО as a pH regulator of the medium allows obtaining a noticeable, economically sound additional recovery of both copper and molybdenum. Quantum chemical calculations have permitted to establish an important feature of the mechanism of interaction between the DC-80 molecules that can form stronger complexes based on -bonds with metal cations of sulfide minerals in comparison with allyl ethers of xanthogenic acids. The energy indicators of the formation of bonds between Cu2S, the DC-80 molecules and allyl ether of xanthic acid were calculated. There were shown the models of the assumed interaction of small mineral particles with air bubbles during flotation, which are determined by physical and chemical properties of the molecules of acetylene-containing reagents. The principal difference between the properties of the foam bubbles formed by acetylene-containing molecules for at least 50% and that of the ordinary foam bubbles formed by standard frothers has been demonstrated in the view of the mechanism of their fixing on the surface of small particles of sulfide minerals and the surface of the bubbles. The optimal flotation mode, comprising a DC-80 reagent, BK-901B and AERO MX-5152 base collectors has been developed. The application of this mode will allow increasing the copper and molybdenum recovery into concentrates by 0.62% and 5.76%, respectively, reducing the flotation time by 35–40%, and improving the quality of resulting concentrates. Based on the research results, it is recommended to incorporate the DC-80 acetylene reagent into the basic flotation mode for conducting pilot tests at the Erdenet Mining Corporation enterprises (Mongolia).
{"title":"Substantiation of the Erdenetiyn-Ovoo copper-molybdenum ore flotation technology with the use of tertiary acetylene alcohol","authors":"T. Yushina, B. Purev, B. Namuungerel","doi":"10.17580/NFM.2020.02.01","DOIUrl":"https://doi.org/10.17580/NFM.2020.02.01","url":null,"abstract":"The article presents the results of a study of the factors affecting the efficiency of the copper-molybdenum ore flotation. The objective of this work was to substantiate and develop a reagent mode for flotation of the Erdenetiyn-Ovoo porphyry copper ores, which makes possible extracting main copper and molybdenum minerals into corresponding concentrates more fully and selectively. It is shown that the use of a DC-80 (2-methyl-3-butin-2-ol) flotation reagent in assosiation with the main base mode reagents — an AERO MX-5152 (a mixture of allyl ethers of xanthogenic acids with n-butyloxycarbonyl-O-n-butylthionocarbamate) combined nonionized collector, a BK-901B (a composition of dialkyldithiophosphate and O,N-dialkyldithiocarbamate) blending ionized collector; diesel fuel; a MIBC (methyl isobutyl carbinol) frother; sodium sulphide Na2S as a modifier and lime СаО as a pH regulator of the medium allows obtaining a noticeable, economically sound additional recovery of both copper and molybdenum. Quantum chemical calculations have permitted to establish an important feature of the mechanism of interaction between the DC-80 molecules that can form stronger complexes based on -bonds with metal cations of sulfide minerals in comparison with allyl ethers of xanthogenic acids. The energy indicators of the formation of bonds between Cu2S, the DC-80 molecules and allyl ether of xanthic acid were calculated. There were shown the models of the assumed interaction of small mineral particles with air bubbles during flotation, which are determined by physical and chemical properties of the molecules of acetylene-containing reagents. The principal difference between the properties of the foam bubbles formed by acetylene-containing molecules for at least 50% and that of the ordinary foam bubbles formed by standard frothers has been demonstrated in the view of the mechanism of their fixing on the surface of small particles of sulfide minerals and the surface of the bubbles. The optimal flotation mode, comprising a DC-80 reagent, BK-901B and AERO MX-5152 base collectors has been developed. The application of this mode will allow increasing the copper and molybdenum recovery into concentrates by 0.62% and 5.76%, respectively, reducing the flotation time by 35–40%, and improving the quality of resulting concentrates. Based on the research results, it is recommended to incorporate the DC-80 acetylene reagent into the basic flotation mode for conducting pilot tests at the Erdenet Mining Corporation enterprises (Mongolia).","PeriodicalId":19653,"journal":{"name":"Nonferrous Metals","volume":"1 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2020-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42491471","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}
Arranging efficient operation of the fleet of induction motors (IM) in non-ferrous metallurgy is a large-scale technical and economic problem. In scientific aspect, the problem is being solved in the framework of two research lines: in developing criteria for the efficient operation of the branch IM fleet and towards the development of methods and tools for implementing the IM fleet efficient operation. The article presents the results of the authors’ work in the mentiond areas. The basis for developing criteria for efficient operation is modeling of current operational states, taking into account the IM operational aging processes. The existing methods and models are poorly focused on fixation of the changes caused by operational aging. There exists a demand for special methods and tools for modeling the IM operational conditions. A mathematical model based on Kolmogorov equations is one of these tools. The system graph and equations of the mathematical model are given. An example of a practical calculation of the no-failure operation probabilities at different rates of repair operations is given. It is stated that the offered mathematical model can serve as an instrument for developing criteria of the IM pool efficient operation. The system of periodic operational diagnostics is ment to be a key element in enhancement of the IM fleet operation efficiency. A topological method worked out for the problems of operational diagnostics is focused upon analyzing the dynamics of operational changes taking place in the IM vector space. The matrix of current deviations is a medium of objective and reliable information about the current IM technical condition. Matching the matrices of current and limiting deviations allows us to make several essential conclusions concerning the IM technical state. The reported study was funded under as a part of state assignment (project number, FSWF-2020–0019), as well as at the expense of RFBR (project number, 20-01-00283).
{"title":"Methods and means of increasing operation efficiency of the fleet of electric motors in non-ferrous metallurgy","authors":"S. Kurilin, M. Dli, Y. Rubin, M. Chernovalova","doi":"10.17580/NFM.2020.02.09","DOIUrl":"https://doi.org/10.17580/NFM.2020.02.09","url":null,"abstract":"Arranging efficient operation of the fleet of induction motors (IM) in non-ferrous metallurgy is a large-scale technical and economic problem. In scientific aspect, the problem is being solved in the framework of two research lines: in developing criteria for the efficient operation of the branch IM fleet and towards the development of methods and tools for implementing the IM fleet efficient operation. The article presents the results of the authors’ work in the mentiond areas. The basis for developing criteria for efficient operation is modeling of current operational states, taking into account the IM operational aging processes. The existing methods and models are poorly focused on fixation of the changes caused by operational aging. There exists a demand for special methods and tools for modeling the IM operational conditions. A mathematical model based on Kolmogorov equations is one of these tools. The system graph and equations of the mathematical model are given. An example of a practical calculation of the no-failure operation probabilities at different rates of repair operations is given. It is stated that the offered mathematical model can serve as an instrument for developing criteria of the IM pool efficient operation. The system of periodic operational diagnostics is ment to be a key element in enhancement of the IM fleet operation efficiency. A topological method worked out for the problems of operational diagnostics is focused upon analyzing the dynamics of operational changes taking place in the IM vector space. The matrix of current deviations is a medium of objective and reliable information about the current IM technical condition. Matching the matrices of current and limiting deviations allows us to make several essential conclusions concerning the IM technical state. The reported study was funded under as a part of state assignment (project number, FSWF-2020–0019), as well as at the expense of RFBR (project number, 20-01-00283).","PeriodicalId":19653,"journal":{"name":"Nonferrous Metals","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2020-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47361942","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}
Two titanium alloys, OT4 and VT6-c, with a pseudo-α and α + β structure, respectively, were brazed using transient liquid phase (TLP) bonding. To obtain high strength joints an amorphous foil (Ti – 12Zr – 22Cu – 12Ni – 1.5 Be – 0.8V wt.%) was used. Based on microstructural studies and analysis of two- and three-component phase diagrams, the mechanism of the microstructural evolution of the brazed seams of titanium alloys OT4 and VT6-c is described. Brazing at 800 °C with exposure for 0.5 h leads to the formation of a heterogeneous structure consisting of Widmanstätten, eutectoid, and eutectic. Brazed OT4 and VT6-c joints with the presence of a eutectic layer in the centre show low mechanical properties; their ultimate strength lies in a range from 200 to 550 MPa. Increasing the brazing temperature to 840 °C and the exposure time to 2 h, leads to the disappearance of the brittle eutectic component from the seam. This structure typically consists of Widmanstätten with a small number of eutectoid fractions. Joints with the absence of a eutectic layer in the brazed seam demonstrate a strength equal to the base titanium alloys. In this case, failure occurs in the base metal. For brazed samples from the OT4 alloy, the tensile strength value is σb = 750 ± 3 MPa, and for samples from VT6-c, σb = 905 ± 3 MPa. This work was supported by Competitiveness Growth Programme of the Federal Autonomous Educational Institution of Higher Education National Research Nuclear University MEPhI (Moscow Engineering Physics Institute).
{"title":"Microstructure formation and mechanical properties of isothermally-solidified titanium alloy joints brazed by a Ti – Zr – Cu – Ni – Be amorphous alloy foil","authors":"P. Morokhov, A. Ivannikov, N. Popov, O. Sevryukov","doi":"10.17580/NFM.2020.02.08","DOIUrl":"https://doi.org/10.17580/NFM.2020.02.08","url":null,"abstract":"Two titanium alloys, OT4 and VT6-c, with a pseudo-α and α + β structure, respectively, were brazed using transient liquid phase (TLP) bonding. To obtain high strength joints an amorphous foil (Ti – 12Zr – 22Cu – 12Ni – 1.5 Be – 0.8V wt.%) was used. Based on microstructural studies and analysis of two- and three-component phase diagrams, the mechanism of the microstructural evolution of the brazed seams of titanium alloys OT4 and VT6-c is described. Brazing at 800 °C with exposure for 0.5 h leads to the formation of a heterogeneous structure consisting of Widmanstätten, eutectoid, and eutectic. Brazed OT4 and VT6-c joints with the presence of a eutectic layer in the centre show low mechanical properties; their ultimate strength lies in a range from 200 to 550 MPa. Increasing the brazing temperature to 840 °C and the exposure time to 2 h, leads to the disappearance of the brittle eutectic component from the seam. This structure typically consists of Widmanstätten with a small number of eutectoid fractions. Joints with the absence of a eutectic layer in the brazed seam demonstrate a strength equal to the base titanium alloys. In this case, failure occurs in the base metal. For brazed samples from the OT4 alloy, the tensile strength value is σb = 750 ± 3 MPa, and for samples from VT6-c, σb = 905 ± 3 MPa. This work was supported by Competitiveness Growth Programme of the Federal Autonomous Educational Institution of Higher Education National Research Nuclear University MEPhI (Moscow Engineering Physics Institute).","PeriodicalId":19653,"journal":{"name":"Nonferrous Metals","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2020-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46690291","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}
The amount of scrapped structures and components made of aluminum alloys is constantly growing along with the increase in the demand for the use of aluminum alloys in various industrial sectors. Uzbekistan has been showing a trend of developing industrial production at a pace typically observed in highly developed countries. In Uzbekistan, the aluminum alloys are used for widespread applications in construction, engineering, energy, chemistry and chemical technology, etc. Due to lack of primary aluminium production facilities in the country, there is a need for the collection and deep processing of the scrapped parts that have fulfilled their useful life. This practice is well implemented and working well for the collection of parts from Al – Si based alloys, also called silumins. The composition, structure and properties of many secondary silumins, which have found application in mechanical engineering, have been developed and improved. For alloys of the Al – Si system, most of research activities focused on property improvement through microalloying as well as improvements in the casting technology and heat treatments. However, it is too early to talk about a systematic approach to improving the operational properties of silumins. This also fully applies to alloys of other systems based on aluminum, for example, Al – Mg alloys, also called magnalias. For Uzbekistan, this is very important, since, as analysis shows, the aluminum alloys of 6XXX family are predominantly used for the construction and building structures. After the development of the first secondary wrought alloy of aluminum with the main alloying element with magnesium, many works were published with the results on improving the composition, structure, properties, processing technologies of secondary magnesia. The published works are notable for the inconsistency of the authors’ positions on microalloying systems and the thermal treatment of secondary magnalias. Regarding silumins, all the results are experimental, there is no systematic approach to the development of new and improvement of the properties of existing alloys from scrapped parts. Based on the experimental results, the article proposes an attempt of a systematic approach to the choice of alloy composition, microalloying systems, optimization of the composition of aluminum alloys for industry.
{"title":"Metal-based systems allowing the use of scrap to prepare aluminum alloys","authors":"Y. Mansurov, J. Rakhmonov, A. Aksyonov","doi":"10.17580/NFM.2020.02.07","DOIUrl":"https://doi.org/10.17580/NFM.2020.02.07","url":null,"abstract":"The amount of scrapped structures and components made of aluminum alloys is constantly growing along with the increase in the demand for the use of aluminum alloys in various industrial sectors. Uzbekistan has been showing a trend of developing industrial production at a pace typically observed in highly developed countries. In Uzbekistan, the aluminum alloys are used for widespread applications in construction, engineering, energy, chemistry and chemical technology, etc. Due to lack of primary aluminium production facilities in the country, there is a need for the collection and deep processing of the scrapped parts that have fulfilled their useful life. This practice is well implemented and working well for the collection of parts from Al – Si based alloys, also called silumins. The composition, structure and properties of many secondary silumins, which have found application in mechanical engineering, have been developed and improved. For alloys of the Al – Si system, most of research activities focused on property improvement through microalloying as well as improvements in the casting technology and heat treatments. However, it is too early to talk about a systematic approach to improving the operational properties of silumins. This also fully applies to alloys of other systems based on aluminum, for example, Al – Mg alloys, also called magnalias. For Uzbekistan, this is very important, since, as analysis shows, the aluminum alloys of 6XXX family are predominantly used for the construction and building structures. After the development of the first secondary wrought alloy of aluminum with the main alloying element with magnesium, many works were published with the results on improving the composition, structure, properties, processing technologies of secondary magnesia. The published works are notable for the inconsistency of the authors’ positions on microalloying systems and the thermal treatment of secondary magnalias. Regarding silumins, all the results are experimental, there is no systematic approach to the development of new and improvement of the properties of existing alloys from scrapped parts. Based on the experimental results, the article proposes an attempt of a systematic approach to the choice of alloy composition, microalloying systems, optimization of the composition of aluminum alloys for industry.","PeriodicalId":19653,"journal":{"name":"Nonferrous Metals","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2020-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45523454","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}
I. Motovilov, Sh. A. Telkov, M. Barmenshinova, A. Nurmanova
Grinding of mineral raw materials of different composition in drum mills with rolling steel tumbling medium is one of the main processes for liberation of mineral complexes and preparation of raw materials for beneficiation. It is known that grinding is one of the most expensive and energy-intensive operations at the ore-preparation process stage. Capital and operational outlays at this stage may reach up to 70% of the factory-wide indicators. In this connection, the reduction of power consumption for the mineral ore-preparation, and especially for grinding, is the topical problem in the mineral dressing technology [1–2]. On a global scale, the Bond work index procedure is most often used to determine the ore grinding power consumption [3]. The scientific literature describes many ways to reduce the ore grinding costs [4–10]. Thus, in [4] the currently central line of solving the problem of improving the efficiency of crushing and grinding processes through the use of modern grinding and classification model-oriented adaptive control system is illustrated by the example of copper-molybdenum ores. The ore grade of quality on-line rating algorithm application for managing the processes is the main approach in this direction. The stability of regulation and quality of grinding of copper-molybdenum ores increases by 5–7% owing to application of such an approach to the industrial process. The principle of crushing in high-pressure rolls (HPR), which allows one to obtain a fine feed for mills, is of practical interest. The emergence of HRP has allowed modifying a multi-stage crushing scheme. The HRP crushing products are characterized not only by a diminished size, but also by a high content of small size grades and increased fissuring, which makes it possible to lessen the volume of mills during subsequent grinding by 30...50% [5]. The authors of [6] present the laboratory studies on the grinding efficiency depending on the grinding bodies used (balls or rods) for various parameters such as granulometric composition, lithological type of copper ore. Examination of the preliminary gravity dressing influence on the Shalkiya deposit complex ore
{"title":"Examination of the preliminary gravity dressing influence on the Shalkiya deposit complex ore","authors":"I. Motovilov, Sh. A. Telkov, M. Barmenshinova, A. Nurmanova","doi":"10.17580/nfm.2019.02.01","DOIUrl":"https://doi.org/10.17580/nfm.2019.02.01","url":null,"abstract":"Grinding of mineral raw materials of different composition in drum mills with rolling steel tumbling medium is one of the main processes for liberation of mineral complexes and preparation of raw materials for beneficiation. It is known that grinding is one of the most expensive and energy-intensive operations at the ore-preparation process stage. Capital and operational outlays at this stage may reach up to 70% of the factory-wide indicators. In this connection, the reduction of power consumption for the mineral ore-preparation, and especially for grinding, is the topical problem in the mineral dressing technology [1–2]. On a global scale, the Bond work index procedure is most often used to determine the ore grinding power consumption [3]. The scientific literature describes many ways to reduce the ore grinding costs [4–10]. Thus, in [4] the currently central line of solving the problem of improving the efficiency of crushing and grinding processes through the use of modern grinding and classification model-oriented adaptive control system is illustrated by the example of copper-molybdenum ores. The ore grade of quality on-line rating algorithm application for managing the processes is the main approach in this direction. The stability of regulation and quality of grinding of copper-molybdenum ores increases by 5–7% owing to application of such an approach to the industrial process. The principle of crushing in high-pressure rolls (HPR), which allows one to obtain a fine feed for mills, is of practical interest. The emergence of HRP has allowed modifying a multi-stage crushing scheme. The HRP crushing products are characterized not only by a diminished size, but also by a high content of small size grades and increased fissuring, which makes it possible to lessen the volume of mills during subsequent grinding by 30...50% [5]. The authors of [6] present the laboratory studies on the grinding efficiency depending on the grinding bodies used (balls or rods) for various parameters such as granulometric composition, lithological type of copper ore. Examination of the preliminary gravity dressing influence on the Shalkiya deposit complex ore","PeriodicalId":19653,"journal":{"name":"Nonferrous Metals","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2019-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48045037","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}
{"title":"Strategy of refining the structure of aluminum-magnesium alloys by complex microalloying with transition elements during casting and subsequent thermomechanical processing","authors":"E. V. Aryshnskii, V. Bazhin, R. Kawalla","doi":"10.17580/NFM.2019.01.05","DOIUrl":"https://doi.org/10.17580/NFM.2019.01.05","url":null,"abstract":"","PeriodicalId":19653,"journal":{"name":"Nonferrous Metals","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2019-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42170210","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}
Nowadays, the effect on the thermal fatigue properties of the complex structure of borides arising in steel joints [1–3] obtained using industrial boron-containing nickel filler metals has been poorly stu died. Studies of borides effect on fatigue mechanisms in the brazed seam by the action of temperature cyclic changes will help to optimize the filler metal compositions, based on Ni – Cr – Si – B system, and obtain the most homogeneous structure. The general trend of increasing the fatigue characteristics of joints can be illustrated by works [4–5]. The resistance of materials, including joints, to fatigue damage is increasingly of interest from the point of view of tests that simulate operating conditions. High operating temperatures and resistance to thermal cyclic loads are a mandatory requirement for many energy-stressed units operating under temperature change conditions [6–9] In such products as rocket nozzles, heat exchangers, gas turbine engine blades, pistons of internal combustion engines, components of atomic technology and energy turbines – the efficiency depends on the operating temperature. Thermal cycling test allows to establish the dependence of thermal fatigue and destruction mechanisms on the microstructure [10–12]. This method is suitable for the qualitative assessment of factors affecting the strength, including fatigue, such as, for example, the elemental composition of the filler metal, the parameters for obtaining a joint or the distribution of stresses. Thus, this method based on a small number of tests may allow an assessment of the fatigue processes and the development of damage in the brazed joint. Thermal fatigue is a destruction of the internal stresses created by cyclically changing the temperature field in the material. Thermal fatigue is possible both in total with external loads and without it. Stresses arise from the irregularity of heating or cooling over the cross section with changes in operating temperature. Stresses can also be structural, as a result of phase transformations and phase hardening. In massive structures heated from the surface, thermal deformations are localized in the surface layer, where the crack grows. Thin-walled structures are destroyed by thermal fatigue where they are tougher: near the corner joints, Thermal fatigue damage of steel joints brazed with various nickel filler metals*
{"title":"Thermal fatigue damage of steel joints brazed with various nickel filler metals","authors":"M. Penyaz, A. Ivannikov, B. Kalin, P. S. Dzhumaev","doi":"10.17580/NFM.2019.01.06","DOIUrl":"https://doi.org/10.17580/NFM.2019.01.06","url":null,"abstract":"Nowadays, the effect on the thermal fatigue properties of the complex structure of borides arising in steel joints [1–3] obtained using industrial boron-containing nickel filler metals has been poorly stu died. Studies of borides effect on fatigue mechanisms in the brazed seam by the action of temperature cyclic changes will help to optimize the filler metal compositions, based on Ni – Cr – Si – B system, and obtain the most homogeneous structure. The general trend of increasing the fatigue characteristics of joints can be illustrated by works [4–5]. The resistance of materials, including joints, to fatigue damage is increasingly of interest from the point of view of tests that simulate operating conditions. High operating temperatures and resistance to thermal cyclic loads are a mandatory requirement for many energy-stressed units operating under temperature change conditions [6–9] In such products as rocket nozzles, heat exchangers, gas turbine engine blades, pistons of internal combustion engines, components of atomic technology and energy turbines – the efficiency depends on the operating temperature. Thermal cycling test allows to establish the dependence of thermal fatigue and destruction mechanisms on the microstructure [10–12]. This method is suitable for the qualitative assessment of factors affecting the strength, including fatigue, such as, for example, the elemental composition of the filler metal, the parameters for obtaining a joint or the distribution of stresses. Thus, this method based on a small number of tests may allow an assessment of the fatigue processes and the development of damage in the brazed joint. Thermal fatigue is a destruction of the internal stresses created by cyclically changing the temperature field in the material. Thermal fatigue is possible both in total with external loads and without it. Stresses arise from the irregularity of heating or cooling over the cross section with changes in operating temperature. Stresses can also be structural, as a result of phase transformations and phase hardening. In massive structures heated from the surface, thermal deformations are localized in the surface layer, where the crack grows. Thin-walled structures are destroyed by thermal fatigue where they are tougher: near the corner joints, Thermal fatigue damage of steel joints brazed with various nickel filler metals*","PeriodicalId":19653,"journal":{"name":"Nonferrous Metals","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2019-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49302449","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}
{"title":"Analysis of technological schemes and substantiation of the selection of the reagent regimes for copper-molybdenum ores flotation","authors":"T. Yushina, K. D'Elia, B. Purev, B. Namuungerel","doi":"10.17580/NFM.2019.01.01","DOIUrl":"https://doi.org/10.17580/NFM.2019.01.01","url":null,"abstract":"","PeriodicalId":19653,"journal":{"name":"Nonferrous Metals","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2019-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47398756","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}
K. G. Anisonyan, D. Y. Kopyev, T. V. Olyunina, G. B. Sadykhov
{"title":"Influence of Na2CO3 and CaCO3 additions on the aluminate slag formation during a single-stage reducing roasting of red mud","authors":"K. G. Anisonyan, D. Y. Kopyev, T. V. Olyunina, G. B. Sadykhov","doi":"10.17580/NFM.2019.01.03","DOIUrl":"https://doi.org/10.17580/NFM.2019.01.03","url":null,"abstract":"","PeriodicalId":19653,"journal":{"name":"Nonferrous Metals","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2019-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45007289","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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