Pub Date : 2022-10-22DOI: 10.3103/S106782122205011X
Yang Xuewei, Chen Xin, Zhang Ting’an, Ye Jiayuan, Lv Guozhi, Zheng Xu
Red mud is another worldwide problem after the bulk solid waste of steel slag.The reaction time between phases of aluminate cement clinker in the molten state is approximately 20 min, and the phase composition obtained is CA. After quenching, a large area of the glass phase appeared in the SEM images of the aluminate cement clinker. The compressive strength and flexural strength at 28 days reached 77.7 and 7.6 MPa, respectively, and the hydration strengths at 1, 3, and 28 days were higher than the strength standard of CA50II aluminate cement.Reconstruction of iron extraction tailings from red mud melting reduction is an effective technology to solve the problems of low cementitious activity, complex composition and large chemical fluctuation of red mud, and it has become an effective technology to improve the comprehensive utilization rate of red mud and promote energy savings and emission reduction.
{"title":"Study on the Cementitious Properties of Aluminate Cement Clinker Prepared from Melt Reduction Slag of Quenched and Tempered High-Iron Red Mud","authors":"Yang Xuewei, Chen Xin, Zhang Ting’an, Ye Jiayuan, Lv Guozhi, Zheng Xu","doi":"10.3103/S106782122205011X","DOIUrl":"10.3103/S106782122205011X","url":null,"abstract":"<p>Red mud is another worldwide problem after the bulk solid waste of steel slag.The reaction time between phases of aluminate cement clinker in the molten state is approximately 20 min, and the phase composition obtained is CA. After quenching, a large area of the glass phase appeared in the SEM images of the aluminate cement clinker. The compressive strength and flexural strength at 28 days reached 77.7 and 7.6 MPa, respectively, and the hydration strengths at 1, 3, and 28 days were higher than the strength standard of CA50II aluminate cement.Reconstruction of iron extraction tailings from red mud melting reduction is an effective technology to solve the problems of low cementitious activity, complex composition and large chemical fluctuation of red mud, and it has become an effective technology to improve the comprehensive utilization rate of red mud and promote energy savings and emission reduction.</p>","PeriodicalId":765,"journal":{"name":"Russian Journal of Non-Ferrous Metals","volume":"63 5","pages":"500 - 509"},"PeriodicalIF":0.8,"publicationDate":"2022-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4876683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-22DOI: 10.3103/S106782122205008X
K. V. Petrova, V. V. Es’kina, V. B. Baranovskaya, M. S. Doronina, N. A. Korotkova, A. A. Arkhipenko
The efficiency of using rare earth metals largely depends on their impurity composition, which affects the structure and properties of materials. Before the analytical control of materials based on rare earth elements (REEs) and the starting materials for their production, the task is to determine both macrocomponents with high accuracy and impurities with high sensitivity, correctness, and precision. To determine the impurities in REE-based materials in the range from 10–5 to 5.0 wt %, a complex of methods of atomic emission and mass spectral analysis is frequently used. However, the analysis of REE-based materials, even using these modern highly sensitive methods, is a difficult task due to spectral and matrix interferences. Therefore, different separation/preconcentration procedures are needed to determine both rare earth and non-rare-earth impurities. This article reviews publications of preconcentration methods for spectral and mass spectral methods of analysis of materials based on REEs and some other analytical methods. It is shown that the most common approaches are liquid extraction and chromatography. Sorption, cloud-point extraction, and precipitation are also used. There is no universal approach. Each method discussed in this article has its advantages and limitations. The analytical completion of the method confirms the effectiveness of the selected separation/preconcentration method in each specific case.
{"title":"Separation and Preconcentration of Impurities in Rare-Earth-Based Materials for Spectrometric Methods","authors":"K. V. Petrova, V. V. Es’kina, V. B. Baranovskaya, M. S. Doronina, N. A. Korotkova, A. A. Arkhipenko","doi":"10.3103/S106782122205008X","DOIUrl":"10.3103/S106782122205008X","url":null,"abstract":"<p>The efficiency of using rare earth metals largely depends on their impurity composition, which affects the structure and properties of materials. Before the analytical control of materials based on rare earth elements (REEs) and the starting materials for their production, the task is to determine both macrocomponents with high accuracy and impurities with high sensitivity, correctness, and precision. To determine the impurities in REE-based materials in the range from 10<sup>–5</sup> to 5.0 wt %, a complex of methods of atomic emission and mass spectral analysis is frequently used. However, the analysis of REE-based materials, even using these modern highly sensitive methods, is a difficult task due to spectral and matrix interferences. Therefore, different separation/preconcentration procedures are needed to determine both rare earth and non-rare-earth impurities. This article reviews publications of preconcentration methods for spectral and mass spectral methods of analysis of materials based on REEs and some other analytical methods. It is shown that the most common approaches are liquid extraction and chromatography. Sorption, cloud-point extraction, and precipitation are also used. There is no universal approach. Each method discussed in this article has its advantages and limitations. The analytical completion of the method confirms the effectiveness of the selected separation/preconcentration method in each specific case.</p>","PeriodicalId":765,"journal":{"name":"Russian Journal of Non-Ferrous Metals","volume":"63 5","pages":"510 - 525"},"PeriodicalIF":0.8,"publicationDate":"2022-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4876684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-22DOI: 10.3103/S1067821222050042
F. V. Grechnikov, Ya. A. Erisov, S. V. Surudin, V. A. Razzhivin
The effect of the cold rolling reduction ratio (εh) on the microstructure and the complex of mechanical and technological properties of cold-rolled sheets from aluminum alloy V-1579 of the Al–Mg–Sc system has been studied. The influence of the final annealing temperature of sheets rolled with different reduction ratios has been examined as well. The character of plastic anisotropy has been found to change slightly with an increase in εh during cold rolling; an increase in tensile strength and yield strength with a decrease in relative elongation is observed. In this case, the anisotropy of the ultimate strength and yield strength is nearly absent. With an increase in the reduction ratio to 30–40%, the anisotropy of the relative elongation increases: the relative elongation in the rolling direction decreases more rapidly. However, after rolling with εh > 50%, the elongation anisotropy almost disappears. Regardless of the annealing temperature, samples rolled with a higher reduction ratio have higher strength characteristics. With an increase in the annealing temperature, the ultimate strength and yield strength decrease, while the relative elongation increases. In this case, softening with the annealing temperature occurs more intensely for samples rolled with a lower reduction. For all analyzed regimes, the character of the distribution of anisotropy indices in the sheet plane does not decrease after annealing and corresponds to the deformation type of textures. Moreover, the in-plane anisotropy coefficient decreases after annealing in comparison with a cold-rolled sample. At the same time, the technological properties of samples rolled with a higher degree of deformation are higher after annealing than those of samples rolled with a lower reduction regardless of the annealing temperature.
{"title":"Influence of the Cold Rolling Reduction Ratio and the Final Annealing Temperature on the Properties and Microstructure of Al–Mg–Sc Alloy Sheets","authors":"F. V. Grechnikov, Ya. A. Erisov, S. V. Surudin, V. A. Razzhivin","doi":"10.3103/S1067821222050042","DOIUrl":"10.3103/S1067821222050042","url":null,"abstract":"<p>The effect of the cold rolling reduction ratio (ε<sub><i>h</i></sub>) on the microstructure and the complex of mechanical and technological properties of cold-rolled sheets from aluminum alloy V-1579 of the Al–Mg–Sc system has been studied. The influence of the final annealing temperature of sheets rolled with different reduction ratios has been examined as well. The character of plastic anisotropy has been found to change slightly with an increase in ε<sub><i>h</i></sub> during cold rolling; an increase in tensile strength and yield strength with a decrease in relative elongation is observed. In this case, the anisotropy of the ultimate strength and yield strength is nearly absent. With an increase in the reduction ratio to 30–40%, the anisotropy of the relative elongation increases: the relative elongation in the rolling direction decreases more rapidly. However, after rolling with ε<sub><i>h</i></sub> > 50%, the elongation anisotropy almost disappears. Regardless of the annealing temperature, samples rolled with a higher reduction ratio have higher strength characteristics. With an increase in the annealing temperature, the ultimate strength and yield strength decrease, while the relative elongation increases. In this case, softening with the annealing temperature occurs more intensely for samples rolled with a lower reduction. For all analyzed regimes, the character of the distribution of anisotropy indices in the sheet plane does not decrease after annealing and corresponds to the deformation type of textures. Moreover, the in-plane anisotropy coefficient decreases after annealing in comparison with a cold-rolled sample. At the same time, the technological properties of samples rolled with a higher degree of deformation are higher after annealing than those of samples rolled with a lower reduction regardless of the annealing temperature.</p>","PeriodicalId":765,"journal":{"name":"Russian Journal of Non-Ferrous Metals","volume":"63 5","pages":"544 - 550"},"PeriodicalIF":0.8,"publicationDate":"2022-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"5177072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-22DOI: 10.3103/S1067821222050091
Miroslav Sokić, Jovica Stojanović, Branislav Marković, Željko Kamberović, Nataša Gajić, Ana Radosavljević-Mihajlović, Dušan Milojkov
This paper examines the effects of structural-textural characteristics of sulfide minerals on their leaching from polymetallic concentrates with sulfuric acid and hydrogen peroxide solutions. The polymetallic concentrate was obtained by flotation of polymetallic ore from the Rudnik deposit in Serbia. X-ray diffraction (XRD), qualitative and quantitative mineralogical, scanning electron microscopy (SEM/EDX), and chemical analyses were used to characterize the polymetallic concentrate and leach residue. The polymetallic concentrate contained chalcopyrite, galena, sphalerite, pyrrhotite, and quartz. The total content of sulfide minerals was 69.5%, and the occurrence of free sulfide mineral grains was about 60.9%. The comprehensive thermodynamic analysis was done by HSC Chemistry® package 9.9.2.3 to determine optimal experimental leaching conditions. Chalcopyrite, sphalerite, and pyrrhotite oxidized during leaching, and dissolution occurred. The oxidized galena remains in the solid residual as insoluble anglesite. Also, elemental sulfur and unleached minerals of copper, zinc, and iron were found in the leach residues. It was found that the structural assembly of sulfide minerals in the leach residue is very favorable and that undissolved sulfide grains are primarily present in free form. Accordingly, there was no reason to reduce the leaching rate with time. The presence of elemental sulfur and anglesite formed in the leaching process and precipitated on the surface of mineral grains was confirmed by XRD, quantitative and qualitative mineralogical analysis, and SEM/EDX.
{"title":"Modification of Structural-Textural Properties of Sulfide Minerals at Polymetallic Concentrate Leaching with Sulfuric Acid and Hydrogen Peroxide Solutions","authors":"Miroslav Sokić, Jovica Stojanović, Branislav Marković, Željko Kamberović, Nataša Gajić, Ana Radosavljević-Mihajlović, Dušan Milojkov","doi":"10.3103/S1067821222050091","DOIUrl":"10.3103/S1067821222050091","url":null,"abstract":"<p>This paper examines the effects of structural-textural characteristics of sulfide minerals on their leaching from polymetallic concentrates with sulfuric acid and hydrogen peroxide solutions. The polymetallic concentrate was obtained by flotation of polymetallic ore from the Rudnik deposit in Serbia. X-ray diffraction (XRD), qualitative and quantitative mineralogical, scanning electron microscopy (SEM/EDX), and chemical analyses were used to characterize the polymetallic concentrate and leach residue. The polymetallic concentrate contained chalcopyrite, galena, sphalerite, pyrrhotite, and quartz. The total content of sulfide minerals was 69.5%, and the occurrence of free sulfide mineral grains was about 60.9%. The comprehensive thermodynamic analysis was done by HSC Chemistry<sup>®</sup> package 9.9.2.3 to determine optimal experimental leaching conditions. Chalcopyrite, sphalerite, and pyrrhotite oxidized during leaching, and dissolution occurred. The oxidized galena remains in the solid residual as insoluble anglesite. Also, elemental sulfur and unleached minerals of copper, zinc, and iron were found in the leach residues. It was found that the structural assembly of sulfide minerals in the leach residue is very favorable and that undissolved sulfide grains are primarily present in free form. Accordingly, there was no reason to reduce the leaching rate with time. The presence of elemental sulfur and anglesite formed in the leaching process and precipitated on the surface of mineral grains was confirmed by XRD, quantitative and qualitative mineralogical analysis, and SEM/EDX.</p>","PeriodicalId":765,"journal":{"name":"Russian Journal of Non-Ferrous Metals","volume":"63 5","pages":"457 - 472"},"PeriodicalIF":0.8,"publicationDate":"2022-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4873885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-22DOI: 10.3103/S1067821222050030
V. I. Bragin, N. F. Usmanova, E. A. Burdakova, A. A. Kondratieva
The results of the studies on the use of collector reagents in the form of a reverse microemulsion (RME) of the water-in-oil type (i.e., water droplets are suspended in the oil phase) for the flotation extraction of lead and zinc minerals are presented. Lead and zinc concentrates and a lead–zinc ore are used as the initial samples for flotation. The concentration of galena in the lead concentrate is 74.7%, and the concentration of sphalerite in the zinc concentrate is 78.7%. Basic collector reagents in the composition of the RME are potassium butyl xanthate (PBX) and kerosene. A nonionic surfactant (NSA) is used to stabilize the RME. Casein is used as additives to the main reagents to eliminate the negative effect of osmotic pressure upon preparing the RME. The transformation of casein to the active soluble form is carried out using sodium sulfide. The particle size in the reverse microemulsion is 12.38 nm. The following options for supplying reagents to the flotation pulp are studied in flotation tests: RME, RME + foaming agent, and potassium butyl xanthate + foaming agent. A T-92 reagent is used as the foaming agent. The consumption of PBX in the composition of the RME and in the classical supply is 26 g/t. The results of laboratory tests show that the method of supplying flotation reagents in the form of an RME leads to an increase both in the flotation rate of lead and zinc sulfides and in their recovery into a foam product. Tests with the use of an RME in the collective flotation cycle of a lead–zinc ore show an increase in the extraction of lead into the total concentrate by 10.8% and zinc by 38.5% in comparison with the classical supply of reagents (collector + foaming agent) in addition to an increase in the flotation rate. An increased selectivity of the action of an RME in relation to zinc sulfides in comparison with lead sulfides is noted. The flotation rate coefficient of sphalerite is 7.8-fold higher when compared to galena. The gain in the extraction into the total zinc concentrate is also higher and is 16.78%, while the gain into the lead concentrate is 1.9% under the same conditions.
{"title":"Application of Reagents in the Form of a Reverse Microemulsion for the Flotation of Lead and Zinc Sulfides","authors":"V. I. Bragin, N. F. Usmanova, E. A. Burdakova, A. A. Kondratieva","doi":"10.3103/S1067821222050030","DOIUrl":"10.3103/S1067821222050030","url":null,"abstract":"<p>The results of the studies on the use of collector reagents in the form of a reverse microemulsion (RME) of the water-in-oil type (i.e., water droplets are suspended in the oil phase) for the flotation extraction of lead and zinc minerals are presented. Lead and zinc concentrates and a lead–zinc ore are used as the initial samples for flotation. The concentration of galena in the lead concentrate is 74.7%, and the concentration of sphalerite in the zinc concentrate is 78.7%. Basic collector reagents in the composition of the RME are potassium butyl xanthate (PBX) and kerosene. A nonionic surfactant (NSA) is used to stabilize the RME. Casein is used as additives to the main reagents to eliminate the negative effect of osmotic pressure upon preparing the RME. The transformation of casein to the active soluble form is carried out using sodium sulfide. The particle size in the reverse microemulsion is 12.38 nm. The following options for supplying reagents to the flotation pulp are studied in flotation tests: RME, RME + foaming agent, and potassium butyl xanthate + foaming agent. A T-92 reagent is used as the foaming agent. The consumption of PBX in the composition of the RME and in the classical supply is 26 g/t. The results of laboratory tests show that the method of supplying flotation reagents in the form of an RME leads to an increase both in the flotation rate of lead and zinc sulfides and in their recovery into a foam product. Tests with the use of an RME in the collective flotation cycle of a lead–zinc ore show an increase in the extraction of lead into the total concentrate by 10.8% and zinc by 38.5% in comparison with the classical supply of reagents (collector + foaming agent) in addition to an increase in the flotation rate. An increased selectivity of the action of an RME in relation to zinc sulfides in comparison with lead sulfides is noted. The flotation rate coefficient of sphalerite is 7.8-fold higher when compared to galena. The gain in the extraction into the total zinc concentrate is also higher and is 16.78%, while the gain into the lead concentrate is 1.9% under the same conditions.</p>","PeriodicalId":765,"journal":{"name":"Russian Journal of Non-Ferrous Metals","volume":"63 5","pages":"482 - 489"},"PeriodicalIF":0.8,"publicationDate":"2022-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4875261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-20DOI: 10.17073/0021-3438-2022-5-78-84
S. Dubinskiy, A. Baranova, V. Brailovski
The influence of heating and cooling routes prior to the Ti–22Nb–6Zr (at.%) shape memory alloy ageing on the intensity of the isothermal ωiso phase formation in the temperature range from 250 to 350 °C for 1 and 3 h was studied by X-ray diffraction. It was shown that for intensive ωiso phase formation, the most efficient scheme for entering the ageing interval includes rapid water cooling to the room temperature from the annealing temperature of 600 °C and subsequent rapid heating to the ageing temperature of 300 °C. All other schemes used for entering the aging interval including slow cooling and/or heating do not lead to the formation of any X-ray identifiable ωiso phase amount. Whereas, the β → ωiso transition in the temperature range from 250 to 350 °C has a pronounced C-shaped kinetics with a maximum at 300 °C. When aged in the entire range of t = 250÷350 °С, the alloy features higher durability and hardness compared to the initial state. Moreover, the hardness gradually increases with an increase in the ageing temperature from 250 to 300 °C and remains constant in the temperature range of t = 300÷350 °С. The β phase lattice parameter of the Ti–22Nb–6Zr alloy remains unchanged over the entire aging temperature range of 250–350 °C, which indicates the absence of noticeable diffusion element redistribution in the solid solution during the ωiso phase formation. The ωiso phase formed during the Ti–22Nb–6Zr alloy ageing over the entire temperature range of t = 250÷350 °С has the ratio сω /аω = 0.613 ± 0.002, which is similar to the сω /аω ratio for the shear-type athermal ωath phase, which in turn further emphasizes the identity of these two phase varieties.
{"title":"Influence of heating and cooling routes on the isothermal β → ω transition in Ti–22Nb–6Zr alloy","authors":"S. Dubinskiy, A. Baranova, V. Brailovski","doi":"10.17073/0021-3438-2022-5-78-84","DOIUrl":"https://doi.org/10.17073/0021-3438-2022-5-78-84","url":null,"abstract":"The influence of heating and cooling routes prior to the Ti–22Nb–6Zr (at.%) shape memory alloy ageing on the intensity of the isothermal ωiso phase formation in the temperature range from 250 to 350 °C for 1 and 3 h was studied by X-ray diffraction. It was shown that for intensive ωiso phase formation, the most efficient scheme for entering the ageing interval includes rapid water cooling to the room temperature from the annealing temperature of 600 °C and subsequent rapid heating to the ageing temperature of 300 °C. All other schemes used for entering the aging interval including slow cooling and/or heating do not lead to the formation of any X-ray identifiable ωiso phase amount. Whereas, the β → ωiso transition in the temperature range from 250 to 350 °C has a pronounced C-shaped kinetics with a maximum at 300 °C. When aged in the entire range of t = 250÷350 °С, the alloy features higher durability and hardness compared to the initial state. Moreover, the hardness gradually increases with an increase in the ageing temperature from 250 to 300 °C and remains constant in the temperature range of t = 300÷350 °С. The β phase lattice parameter of the Ti–22Nb–6Zr alloy remains unchanged over the entire aging temperature range of 250–350 °C, which indicates the absence of noticeable diffusion element redistribution in the solid solution during the ωiso phase formation. The ωiso phase formed during the Ti–22Nb–6Zr alloy ageing over the entire temperature range of t = 250÷350 °С has the ratio сω /аω = 0.613 ± 0.002, which is similar to the сω /аω ratio for the shear-type athermal ωath phase, which in turn further emphasizes the identity of these two phase varieties.","PeriodicalId":765,"journal":{"name":"Russian Journal of Non-Ferrous Metals","volume":"99 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85770999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-20DOI: 10.17073/0021-3438-2022-5-85-86
A. Editorial
.
．
{"title":"In memory of Vladimir Ivanovich Nikitin","authors":"A. Editorial","doi":"10.17073/0021-3438-2022-5-85-86","DOIUrl":"https://doi.org/10.17073/0021-3438-2022-5-85-86","url":null,"abstract":"<jats:p>.</jats:p>","PeriodicalId":765,"journal":{"name":"Russian Journal of Non-Ferrous Metals","volume":"69 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87753234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-20DOI: 10.17073/0021-3438-2022-5-55-65
V. K. Dubrovin, B. A. Kulakov, A. V. Karpinskii, O. M. Zaslavskaia
The paper provides the results of studies on interaction between titanium melts and silica-containing investment molds. Pure silicon, compounds of titanium oxides and silicides were detected by X-ray diffraction analysis in the contact zone. The problem of the negative impact exerted by the mold on the casting is solved by using thermally stable and chemically resistant monocorundum molds based on an alumina sol binder. A refractory suspension was developed for investment casting containing special additives to improve wax mold wetting with the suspension, and to increase the mold shell strength. The article studies sedimentation properties of suspension. A method was developed for accelerated curing of sequentially applied refractory suspension layers by vacuum drying and subsequent chemical curing with a gaseous reagent. The formation time is reduced from 3–5 h to 20–30 min per layer. Comparative studies of kinetics of alumina sol binder convective drying and vacuum dehydration were conducted. The process of moisture removal per unit surface of the applied refractory layer in a vacuum of 5–10 kPa increases by 2–6 times. X-ray phase analysis was used to study the alumina sol conversion during high-temperature heating. The solid gel of the α-Al2O3 stable phase is obtained in the alumina sol mold shell when the calcination temperature rises to 1300–1350 °C with a sufficient strength of 9–12 MPa provided by sintering additives added to the suspension. Recommendations are given for additional protection of refractory ceramic layers after vacuuming and drying: treatment of the last layer with gaseous curing agents and application of a polyvinylacetal solution with a density of 1100–1200 kg/m3. The process solutions proposed will make it possible to increase both the efficiency of titanium alloy forming and casting processes and the quality of castings.
{"title":"New process solutions in the manufacture of thermochemically resistant ceramic molds for casting titanium alloys","authors":"V. K. Dubrovin, B. A. Kulakov, A. V. Karpinskii, O. M. Zaslavskaia","doi":"10.17073/0021-3438-2022-5-55-65","DOIUrl":"https://doi.org/10.17073/0021-3438-2022-5-55-65","url":null,"abstract":"The paper provides the results of studies on interaction between titanium melts and silica-containing investment molds. Pure silicon, compounds of titanium oxides and silicides were detected by X-ray diffraction analysis in the contact zone. The problem of the negative impact exerted by the mold on the casting is solved by using thermally stable and chemically resistant monocorundum molds based on an alumina sol binder. A refractory suspension was developed for investment casting containing special additives to improve wax mold wetting with the suspension, and to increase the mold shell strength. The article studies sedimentation properties of suspension. A method was developed for accelerated curing of sequentially applied refractory suspension layers by vacuum drying and subsequent chemical curing with a gaseous reagent. The formation time is reduced from 3–5 h to 20–30 min per layer. Comparative studies of kinetics of alumina sol binder convective drying and vacuum dehydration were conducted. The process of moisture removal per unit surface of the applied refractory layer in a vacuum of 5–10 kPa increases by 2–6 times. X-ray phase analysis was used to study the alumina sol conversion during high-temperature heating. The solid gel of the α-Al2O3 stable phase is obtained in the alumina sol mold shell when the calcination temperature rises to 1300–1350 °C with a sufficient strength of 9–12 MPa provided by sintering additives added to the suspension. Recommendations are given for additional protection of refractory ceramic layers after vacuuming and drying: treatment of the last layer with gaseous curing agents and application of a polyvinylacetal solution with a density of 1100–1200 kg/m3. The process solutions proposed will make it possible to increase both the efficiency of titanium alloy forming and casting processes and the quality of castings.","PeriodicalId":765,"journal":{"name":"Russian Journal of Non-Ferrous Metals","volume":"85 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88758521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-20DOI: 10.17073/0022-3438-2021-5-46-54
E. Prusov, V. Deev, A. Aborkin, A. Panfilov, A. Kireev
The lack of understanding as to the nature of interfacial interaction between reinforcing particles and the matrix alloy during repeated remelting of cast composite materials is one of the problems hindering the expansion of their industrial application. This research is aimed at establishing the effect of repeated remelting of AK12 + 10 vol.% SiC aluminum matrix composites on the retention and chemical stability of silicon carbide reinforcing particles. It is shown that an increase in the number of remelting iterations is not accompanied by any new phases appearing at the interfaces between particles and the matrix, which indicates the stability of the SiC reinforcing phase in aluminumsilicon melts under the considered temperature-time and concentration conditions. Repeated remelting of aluminum matrix composites with silicon carbide shifts the particle distribution uniformity towards a more uniform distribution degree (on average 0.81046 at the first remelting iteration, 0.6901 at the second one and 0.5609 at the third one) and slightly reduces their average sizes (from 70.74 μm at the first iteration to 65.76 μm at the second one and 61.21 μm at the third one), apparently due to particle fragmentation that leads to an increase in the quantity of finer particles. At the same time, the share of the area occupied by particles in the section regions under consideration remains practically unchanged (10.9293, 10.9607 and 11.6483 % at the first, second and third remelting iterations, respectively). In the course of repeated remelting of Al–SiC aluminum matrix composites, processes of reinforcing particle redistribution occur that lead to the destruction of agglomerates even without intensive mixing with an impeller. Due to this, the uniformity of particle distribution in the structure of secondary aluminum matrix composite ingots can be significantly improved.
{"title":"Structure and phase composition formation of cast aluminum matrix composites during multiple remelting","authors":"E. Prusov, V. Deev, A. Aborkin, A. Panfilov, A. Kireev","doi":"10.17073/0022-3438-2021-5-46-54","DOIUrl":"https://doi.org/10.17073/0022-3438-2021-5-46-54","url":null,"abstract":"The lack of understanding as to the nature of interfacial interaction between reinforcing particles and the matrix alloy during repeated remelting of cast composite materials is one of the problems hindering the expansion of their industrial application. This research is aimed at establishing the effect of repeated remelting of AK12 + 10 vol.% SiC aluminum matrix composites on the retention and chemical stability of silicon carbide reinforcing particles. It is shown that an increase in the number of remelting iterations is not accompanied by any new phases appearing at the interfaces between particles and the matrix, which indicates the stability of the SiC reinforcing phase in aluminumsilicon melts under the considered temperature-time and concentration conditions. Repeated remelting of aluminum matrix composites with silicon carbide shifts the particle distribution uniformity towards a more uniform distribution degree (on average 0.81046 at the first remelting iteration, 0.6901 at the second one and 0.5609 at the third one) and slightly reduces their average sizes (from 70.74 μm at the first iteration to 65.76 μm at the second one and 61.21 μm at the third one), apparently due to particle fragmentation that leads to an increase in the quantity of finer particles. At the same time, the share of the area occupied by particles in the section regions under consideration remains practically unchanged (10.9293, 10.9607 and 11.6483 % at the first, second and third remelting iterations, respectively). In the course of repeated remelting of Al–SiC aluminum matrix composites, processes of reinforcing particle redistribution occur that lead to the destruction of agglomerates even without intensive mixing with an impeller. Due to this, the uniformity of particle distribution in the structure of secondary aluminum matrix composite ingots can be significantly improved.","PeriodicalId":765,"journal":{"name":"Russian Journal of Non-Ferrous Metals","volume":"30 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74689687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-19DOI: 10.17073/0021-3438-2022-5-36-45
R. Asfandiyarov, G. Raab, D. Gunderov, D. Aksenov, A. G. Raab
An effective approach to increasing the fatigue resistance of metal products is to create compressive residual stresses on the surface of the product using surface plastic deformation (SPD) processing. One of the effective SPD methods is the process of abrasive-free ultrasonic finishing (AFUF). Another well-known approach to improving mechanical properties including fatigue resistance is to create an ultrafinegrained (UFG) structural state in the product. This research focuses on the finite-element study of the stress-strain state of a UFG workpiece subjected to SPD by the AFUF method. Commercially pure Grade 4 titanium in the UFG state obtained by the ECAP-Conform method was chosen as a workpiece material. In the course of the study, the stress-strain state of the deformation zone was analyzed after a single indentation with subsequent unloading under the elastic-plastic scenario. The effect of the indenter oscillation amplitude and its geometry on radial residual stresses including their depth of occurrence, average normal stress and strain intensity was analyzed. It was found that as the indenter radius increases, the strain intensity (e) value decreases. The e parameter distribution has a gradient nature with a decrease in values from the surface to the center of the workpiece. An analysis of simulation results shows that radial residual stresses in the deformation zone are predominantly compressive, and, accordingly, they will increase the fatigue resistance of the finished product. It was established that as the indenter oscillation amplitude increases, the values of compressive radial residual stresses also increase. Their maximum values reach 540 MPa at an amplitude of 75 μm with the depth of these stresses up to 0.3 mm. An increase in the indenter radius, i.e. in fact the contact area, leads to an increase in the magnitude of compressive radial residual stresses with an almost linear behavior.
{"title":"Finite element analysis of stress-strain state of the deformation zone of a UFG TI Grade 4 workpiece subjected to abrasive-free ultrasonic finishing","authors":"R. Asfandiyarov, G. Raab, D. Gunderov, D. Aksenov, A. G. Raab","doi":"10.17073/0021-3438-2022-5-36-45","DOIUrl":"https://doi.org/10.17073/0021-3438-2022-5-36-45","url":null,"abstract":"An effective approach to increasing the fatigue resistance of metal products is to create compressive residual stresses on the surface of the product using surface plastic deformation (SPD) processing. One of the effective SPD methods is the process of abrasive-free ultrasonic finishing (AFUF). Another well-known approach to improving mechanical properties including fatigue resistance is to create an ultrafinegrained (UFG) structural state in the product. This research focuses on the finite-element study of the stress-strain state of a UFG workpiece subjected to SPD by the AFUF method. Commercially pure Grade 4 titanium in the UFG state obtained by the ECAP-Conform method was chosen as a workpiece material. In the course of the study, the stress-strain state of the deformation zone was analyzed after a single indentation with subsequent unloading under the elastic-plastic scenario. The effect of the indenter oscillation amplitude and its geometry on radial residual stresses including their depth of occurrence, average normal stress and strain intensity was analyzed. It was found that as the indenter radius increases, the strain intensity (e) value decreases. The e parameter distribution has a gradient nature with a decrease in values from the surface to the center of the workpiece. An analysis of simulation results shows that radial residual stresses in the deformation zone are predominantly compressive, and, accordingly, they will increase the fatigue resistance of the finished product. It was established that as the indenter oscillation amplitude increases, the values of compressive radial residual stresses also increase. Their maximum values reach 540 MPa at an amplitude of 75 μm with the depth of these stresses up to 0.3 mm. An increase in the indenter radius, i.e. in fact the contact area, leads to an increase in the magnitude of compressive radial residual stresses with an almost linear behavior.","PeriodicalId":765,"journal":{"name":"Russian Journal of Non-Ferrous Metals","volume":"7 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83896581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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