R. Younes, Abelhamid Sadeddine, M. A. Bradai, Sahraoui Aissat, A. Benabbas
Abstract Mechanical properties, wear resistance and impact resistance of a high-alloy chromium cast iron used in the fabrication of grinding balls have been studied. A rank of tempering heat treatments under several temperatures 500°C, 525°C, 550°C and 575°C was performed after austenitized at 1050°C. The Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD) techniques have been used to characterize the microstructures and identify the phases. The wear balls tests were conducted in a rotating drum with a velocity 0.5 r/s. The tribological tests were carried out by evaluated a weight loss as function time. The measurement of the rebound resilience was determined by Charpy impact tests. The results of XRD showed the presence of the martensite, carbides type M7C3 and M2C for all tempering heat treated. The hardness of the sample increased after the tempering and reach nearly 65 HRC at 1050°C. In another hand, it decreased after the tempering treatment it could be explained by precipitation of the carbides type M2C.
{"title":"Investigation on the Influence of Tempering on Microstructure and Wear Properties of High Alloy Chromium Cast Iron","authors":"R. Younes, Abelhamid Sadeddine, M. A. Bradai, Sahraoui Aissat, A. Benabbas","doi":"10.2478/adms-2021-0011","DOIUrl":"https://doi.org/10.2478/adms-2021-0011","url":null,"abstract":"Abstract Mechanical properties, wear resistance and impact resistance of a high-alloy chromium cast iron used in the fabrication of grinding balls have been studied. A rank of tempering heat treatments under several temperatures 500°C, 525°C, 550°C and 575°C was performed after austenitized at 1050°C. The Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD) techniques have been used to characterize the microstructures and identify the phases. The wear balls tests were conducted in a rotating drum with a velocity 0.5 r/s. The tribological tests were carried out by evaluated a weight loss as function time. The measurement of the rebound resilience was determined by Charpy impact tests. The results of XRD showed the presence of the martensite, carbides type M7C3 and M2C for all tempering heat treated. The hardness of the sample increased after the tempering and reach nearly 65 HRC at 1050°C. In another hand, it decreased after the tempering treatment it could be explained by precipitation of the carbides type M2C.","PeriodicalId":7327,"journal":{"name":"Advances in Materials Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84214354","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}
Abstract The aircraft industry is striving to reduce the weight of aircraft to save fuel and hence reduce total cost. New alloys and composites with properties such as low weight and high strength are continuously developed. Titanium alloys have the best strength-to-weight ratio among metals which makes them very suitable for aircraft applications. Ti-64 is the most common Titanium alloy used in aircraft. AA2099 is a 3rd generation Al-Li alloy and has the lowest density among all Aluminium alloys making it very attractive for aircraft applications. Pylons of commercial aircraft are currently made primarily with Ti-64 and this study focused on the replacement of Ti-64 with AA2099. Loading conditions, operating temperature, corrosion resistance, manufacturability and recyclability of the pylon were analysed of both Ti-64 and AA2099. Three critical scenarios were chosen for the loading conditions of the pylon. These were simulated using finite element analysis first using Ti-64 and then AA2099. From the results, it is evident that using AA2099 as the material of the pylon instead of Ti-64 offered weight savings. The operating temperature, manufacturability and recyclability also showed advantages when using AA2099 whereas corrosion factors favoured Ti-64, since AA2099 was found to be very prone to galvanic corrosion.
{"title":"Substituting Ti-64 with Aa2099 as Material of a Commercial Aircraft Pylon","authors":"H. Khalid, Ares A. Gomez-Gallegos","doi":"10.2478/adms-2021-0012","DOIUrl":"https://doi.org/10.2478/adms-2021-0012","url":null,"abstract":"Abstract The aircraft industry is striving to reduce the weight of aircraft to save fuel and hence reduce total cost. New alloys and composites with properties such as low weight and high strength are continuously developed. Titanium alloys have the best strength-to-weight ratio among metals which makes them very suitable for aircraft applications. Ti-64 is the most common Titanium alloy used in aircraft. AA2099 is a 3rd generation Al-Li alloy and has the lowest density among all Aluminium alloys making it very attractive for aircraft applications. Pylons of commercial aircraft are currently made primarily with Ti-64 and this study focused on the replacement of Ti-64 with AA2099. Loading conditions, operating temperature, corrosion resistance, manufacturability and recyclability of the pylon were analysed of both Ti-64 and AA2099. Three critical scenarios were chosen for the loading conditions of the pylon. These were simulated using finite element analysis first using Ti-64 and then AA2099. From the results, it is evident that using AA2099 as the material of the pylon instead of Ti-64 offered weight savings. The operating temperature, manufacturability and recyclability also showed advantages when using AA2099 whereas corrosion factors favoured Ti-64, since AA2099 was found to be very prone to galvanic corrosion.","PeriodicalId":7327,"journal":{"name":"Advances in Materials Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84284794","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}
S. Voinarovych, D. Alontseva, O. Kyslytsia, S. Kaliuzhnyi, A. Khozhanov, A. Krasavin, T. Kolesnikova
Abstract This paper presents new results of studying the influence of parameters of microplasma spraying (MPS) of Zr wire on the structure of Zr coatings. The coating experiments were accomplished in a two level fractional factorial design. Individual particles of sprayed Zr wire and their splats on the substrate were collected under various spraying parameters (amperage, spraying distance, plasma gas flow rate and wire flow rate) and evaluated by Scanning Electron Microscopy (SEM) to establish the effect of particle size and shape on the coating microstructure. The particles were characterized by measurement of their sizes and the obtained results were evaluated in terms of their degree of melting. This was compared with the experimentally observed coating microstructure type and finally correlated to the investigated coating porosity to select the specific MPS parameters of Zr coatings depositing onto medical implants from Ti alloy. It was found that the main parameters influencing the size of the sprayed Zr particles and the porosity of the Zr coatings are the plasma gas flow rate and amperage. It was demonstrated that it is possible to control the porosity of Zr microplasma coatings in the range from 2.8% to 20.3% by changing the parameters of the MPS. The parameters of microplasma spraying of Zr wire were established to obtain medical implant coatings with porosity up to 20.3% and pore size up to 300 μm.
{"title":"Fabrication and Characterization of Zr Microplasma Sprayed Coatings for Medical Applications","authors":"S. Voinarovych, D. Alontseva, O. Kyslytsia, S. Kaliuzhnyi, A. Khozhanov, A. Krasavin, T. Kolesnikova","doi":"10.2478/adms-2021-0013","DOIUrl":"https://doi.org/10.2478/adms-2021-0013","url":null,"abstract":"Abstract This paper presents new results of studying the influence of parameters of microplasma spraying (MPS) of Zr wire on the structure of Zr coatings. The coating experiments were accomplished in a two level fractional factorial design. Individual particles of sprayed Zr wire and their splats on the substrate were collected under various spraying parameters (amperage, spraying distance, plasma gas flow rate and wire flow rate) and evaluated by Scanning Electron Microscopy (SEM) to establish the effect of particle size and shape on the coating microstructure. The particles were characterized by measurement of their sizes and the obtained results were evaluated in terms of their degree of melting. This was compared with the experimentally observed coating microstructure type and finally correlated to the investigated coating porosity to select the specific MPS parameters of Zr coatings depositing onto medical implants from Ti alloy. It was found that the main parameters influencing the size of the sprayed Zr particles and the porosity of the Zr coatings are the plasma gas flow rate and amperage. It was demonstrated that it is possible to control the porosity of Zr microplasma coatings in the range from 2.8% to 20.3% by changing the parameters of the MPS. The parameters of microplasma spraying of Zr wire were established to obtain medical implant coatings with porosity up to 20.3% and pore size up to 300 μm.","PeriodicalId":7327,"journal":{"name":"Advances in Materials Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86493472","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}
Abstract The article presents the results of modelling the friction phenomenon using artificial neural networks and analysis of variance. The test material was composed of strip specimens made of 0.5-mm-thick alpha-beta Grade 5 (Ti-6Al-4V) titanium alloy sheet. A special tribotester was used in the tests to simulate the friction conditions between the punch and the sheet metal in the sheet metal forming process. A test called the strip drawing test has been conducted in conditions in which the sheet surface is lubricated with six environmentally friendly oils (palm, coconut, olive, sunflower, soybean and linseed). Based on the results of the strip drawing test, a regression model and an artificial neural network model were built to determine the complex interactions between the process parameters and the friction coefficient. A multilayer perceptron with one hidden layer and eight neurons in this layer showed the best fit to the training data. The network training was conducted using three algorithms, i.e. Levenberg-Marquardt, back propagation and quasi-Newton. Taking into consideration both the coefficient of determination R2 (0.962) and S.D. ratio (0.272), the best regression characteristics were presented by the network trained using the Levenberg-Marquardt algorithm. From the response surfaces of the quadratic regression model it was found that an increase in the density of lubricant at a specific pressure causes a reduction in the coefficient of friction. Low density and high kinematic viscosity of the oil leads to a high coefficient of friction.
{"title":"Multivariate Modelling of Effectiveness of Lubrication of Ti-6al-4v Titanium Alloy Sheet using Vegetable Oil-Based Lubricants","authors":"T. Trzepieciński, Marcin Szpunar","doi":"10.2478/adms-2021-0009","DOIUrl":"https://doi.org/10.2478/adms-2021-0009","url":null,"abstract":"Abstract The article presents the results of modelling the friction phenomenon using artificial neural networks and analysis of variance. The test material was composed of strip specimens made of 0.5-mm-thick alpha-beta Grade 5 (Ti-6Al-4V) titanium alloy sheet. A special tribotester was used in the tests to simulate the friction conditions between the punch and the sheet metal in the sheet metal forming process. A test called the strip drawing test has been conducted in conditions in which the sheet surface is lubricated with six environmentally friendly oils (palm, coconut, olive, sunflower, soybean and linseed). Based on the results of the strip drawing test, a regression model and an artificial neural network model were built to determine the complex interactions between the process parameters and the friction coefficient. A multilayer perceptron with one hidden layer and eight neurons in this layer showed the best fit to the training data. The network training was conducted using three algorithms, i.e. Levenberg-Marquardt, back propagation and quasi-Newton. Taking into consideration both the coefficient of determination R2 (0.962) and S.D. ratio (0.272), the best regression characteristics were presented by the network trained using the Levenberg-Marquardt algorithm. From the response surfaces of the quadratic regression model it was found that an increase in the density of lubricant at a specific pressure causes a reduction in the coefficient of friction. Low density and high kinematic viscosity of the oil leads to a high coefficient of friction.","PeriodicalId":7327,"journal":{"name":"Advances in Materials Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86703754","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}
Abstract The influences of processing parameters and tool feature on the microstructure of AA1100 and AA3003 aluminium alloys were investigated using bobbin friction stir welding (BFSW). The research includes flow visualization and microstructural evolution of the weld texture using the metallographic measurement method. Results indicated that the operational parameters of the welding (e.g. feed rate, rotating speed) and the geometry of the tool can directly affect the flow patterns of the weld structure. The microscopic details revealed by the optical and electron microscope imply the dynamic recrystallization including grain refinement and precipitation mechanisms within the stirring zone of the weld region. The microscopic observations for the weld samples show a better performance of the fully-featured tool (tri-flat threaded pin and scrolled shoulders) compared to the simple tool without inscribed surface features. The fully-featured tool resulted in a more uniform thermomechanical plastic deformation within the weld structure along with the precipitation hardening and the homogeneity of the microstructure.
{"title":"Internal Flow Behaviour and Microstructural Evolution of the Bobbin-FSW Welds: Thermomechanical Comparison between 1xxx and 3xxx Aluminium Grades","authors":"A. Tamadon, D. Pons, Kamil Sued, D. Clucas","doi":"10.2478/adms-2021-0010","DOIUrl":"https://doi.org/10.2478/adms-2021-0010","url":null,"abstract":"Abstract The influences of processing parameters and tool feature on the microstructure of AA1100 and AA3003 aluminium alloys were investigated using bobbin friction stir welding (BFSW). The research includes flow visualization and microstructural evolution of the weld texture using the metallographic measurement method. Results indicated that the operational parameters of the welding (e.g. feed rate, rotating speed) and the geometry of the tool can directly affect the flow patterns of the weld structure. The microscopic details revealed by the optical and electron microscope imply the dynamic recrystallization including grain refinement and precipitation mechanisms within the stirring zone of the weld region. The microscopic observations for the weld samples show a better performance of the fully-featured tool (tri-flat threaded pin and scrolled shoulders) compared to the simple tool without inscribed surface features. The fully-featured tool resulted in a more uniform thermomechanical plastic deformation within the weld structure along with the precipitation hardening and the homogeneity of the microstructure.","PeriodicalId":7327,"journal":{"name":"Advances in Materials Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84634496","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}
R. Yamanoğlu, É. Fazakas, F. Ahnia, D. Alontseva, F. Khoshnaw
Abstract This study aims to investigate the influence of adding a coating layer of austenitic stainless steel type 316L on Ti6Al4V alloy on corrosion behaviour. Samples of 316L, Ti6Al4V, and 316L on Ti6Al4V were prepared by hot-press sintering of their powders. The potentiodynamic polarization technique was used to characterize the corrosion behaviour of the samples in 0.9 and 3.5 wt. % NaCl concentrations. The corrosion potential (Ecorr.), current density (icorr) and corrosion rate (CR) of the sintered samples were compared in this study. The results showed that 316L samples had the best corrosion resistance, although micropits were observed on the surface, while Ti6Al4V samples had the lowest. This corrosion behaviour of sintered 316L samples can be interrelated to the existence of a passive layer on stainless steel alloys that can be attacked by chloride ions and causing localized corrosion. In general, the CR values of Ti6Al4V samples coated by 316L were between the 316L and Ti6Al4V samples. The CR values of the samples, in 0.9 wt. % NaCl, did not show significant changes with increasing time, as the CR for 316L values were around 0.003 mm/year, while for Ti6Al4V the CR values changed noticeably from 0.018 mm/year of 0 hr, to 0.015 mm/year for 24 hours. However, the changes were less than that of Ti6Al4V. For 3.5 wt. % NaCl solution, although the same order of CR remained, i.e., the CR values of coated Ti6Al4V samples were between 316L (lowest) and Ti6Al4V (highest), the overall CR values for the samples were higher than 0.9 wt. % NaCl.
{"title":"Pitting Corrosion behaviour of Austenitic Stainless-Steel Coated on Ti6Al4V Alloy in Chloride Solutions","authors":"R. Yamanoğlu, É. Fazakas, F. Ahnia, D. Alontseva, F. Khoshnaw","doi":"10.2478/adms-2021-0007","DOIUrl":"https://doi.org/10.2478/adms-2021-0007","url":null,"abstract":"Abstract This study aims to investigate the influence of adding a coating layer of austenitic stainless steel type 316L on Ti6Al4V alloy on corrosion behaviour. Samples of 316L, Ti6Al4V, and 316L on Ti6Al4V were prepared by hot-press sintering of their powders. The potentiodynamic polarization technique was used to characterize the corrosion behaviour of the samples in 0.9 and 3.5 wt. % NaCl concentrations. The corrosion potential (Ecorr.), current density (icorr) and corrosion rate (CR) of the sintered samples were compared in this study. The results showed that 316L samples had the best corrosion resistance, although micropits were observed on the surface, while Ti6Al4V samples had the lowest. This corrosion behaviour of sintered 316L samples can be interrelated to the existence of a passive layer on stainless steel alloys that can be attacked by chloride ions and causing localized corrosion. In general, the CR values of Ti6Al4V samples coated by 316L were between the 316L and Ti6Al4V samples. The CR values of the samples, in 0.9 wt. % NaCl, did not show significant changes with increasing time, as the CR for 316L values were around 0.003 mm/year, while for Ti6Al4V the CR values changed noticeably from 0.018 mm/year of 0 hr, to 0.015 mm/year for 24 hours. However, the changes were less than that of Ti6Al4V. For 3.5 wt. % NaCl solution, although the same order of CR remained, i.e., the CR values of coated Ti6Al4V samples were between 316L (lowest) and Ti6Al4V (highest), the overall CR values for the samples were higher than 0.9 wt. % NaCl.","PeriodicalId":7327,"journal":{"name":"Advances in Materials Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81902179","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}
Abstract The article presents the results of the preliminary research of tribological properties of flame sprayed nickel and aluminum coatings reinforced with carbon nanotubes made on the structural steel S235J0 substrate. The carbon material – carbon nanotubes Nanocyl NC 7000 (0.5 wt.% and 1 wt.%) was used for structural reinforcement. The properties evaluation was made by the use of optical microscopy, scanning electron microscopy, Raman spectroscopy, microhardness measurements, and by means of abrasion and erosion resistance laboratory tests. The obtained results were compared with pure nickel powder coatings 2N5 (Ni 99.5%) and with pure aluminum powder coatings (EN AW 1000 series). It was proved that the flame spraying of nickel and aluminum coatings reinforced with particles carbonaceous material can be an effective alternative for other more advanced surfacing technology. The preliminary test results will be successively extended by further experiments to contribute in the near future to develop innovative technologies, that can be implemented in the aviation industry and the automotive. The presented research is a continuation of the work previously published.
{"title":"Properties of Flame Spraying Coatings Reinforced with Particles of Carbon Nanotubes","authors":"A. Czupryński, C. Mele","doi":"10.2478/adms-2021-0005","DOIUrl":"https://doi.org/10.2478/adms-2021-0005","url":null,"abstract":"Abstract The article presents the results of the preliminary research of tribological properties of flame sprayed nickel and aluminum coatings reinforced with carbon nanotubes made on the structural steel S235J0 substrate. The carbon material – carbon nanotubes Nanocyl NC 7000 (0.5 wt.% and 1 wt.%) was used for structural reinforcement. The properties evaluation was made by the use of optical microscopy, scanning electron microscopy, Raman spectroscopy, microhardness measurements, and by means of abrasion and erosion resistance laboratory tests. The obtained results were compared with pure nickel powder coatings 2N5 (Ni 99.5%) and with pure aluminum powder coatings (EN AW 1000 series). It was proved that the flame spraying of nickel and aluminum coatings reinforced with particles carbonaceous material can be an effective alternative for other more advanced surfacing technology. The preliminary test results will be successively extended by further experiments to contribute in the near future to develop innovative technologies, that can be implemented in the aviation industry and the automotive. The presented research is a continuation of the work previously published.","PeriodicalId":7327,"journal":{"name":"Advances in Materials Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85499161","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}
Abstract Wastewaters from dairy processing factories contaminated with α-oxypropionic acid were monitored. Theoretical analysis of industrial wastewater treatment methods on zeolites of Sokyrnytsia deposit was carried out. The process of sorption of α-oxypropionic (α-oxypropionic) acid by natural zeolite of Sokyrnytsia deposit was considered. It was established that the most economically advantageous and safe is the method of adsorption using a natural sorbent - zeolite, which provides the lowest concentration of contaminants in treated wastewaters from dairies. An assessment of their number, localization features and measures of toxicological impact on the environment was done. The existing theoretical apparatus of description of adsorption processes was analyzed. The sorption properties of natural zeolite (clinoptilolite of Sokyrnytsia deposit) and activated carbon to α-oxypropionic acid were tested. Equilibrium values of adsorption capacity were calculated and corresponding isotherms at a temperature of 20 ° С were constructed. The porosity of the sorbent and its influence on the sorption properties were studied by the methods of physicochemical analysis. Infrared spectroscopic and electron microscopic studies confirmed the presence of the process of sorption by the surface of the internal pores of the zeolite of α-oxypropionic acid molecules. Experimental studies have confirmed the possibility of using natural zeolite for wastewater treatment of dairy factories. It was experimentally confirmed by physicochemical methods of analysis (electron microscopy, IR spectroscopy, microprobe analysis, mercury porometry) and was established that the process takes place both by the mechanism of ion exchange and physical adsorption. The content of carbon radicals in the zeolite matrix after the sorption process was confirmed by X-ray spectral microanalysis. The ability of zeolite to adsorb organic carboxylic acid radicals was confirmed by the results of IR spectroscopic studies. On the IR spectra there are strips of deformation and valence oscillations of the groups of the crystal lattice of the zeolite Si-O, Si-O-SiOH: 452, 990–1210, 1638, 3368 cm−1. The oscillation spectra of free OH groups in the region of 2600 cm−1 were revealed.
{"title":"Regularities of Adsorption of Α-Oxypropionic Acid By Natural Zeolite","authors":"V. Sabadash, J. Gumnitsky, O. Lyuta, A. Hyvlyud","doi":"10.2478/adms-2021-0004","DOIUrl":"https://doi.org/10.2478/adms-2021-0004","url":null,"abstract":"Abstract Wastewaters from dairy processing factories contaminated with α-oxypropionic acid were monitored. Theoretical analysis of industrial wastewater treatment methods on zeolites of Sokyrnytsia deposit was carried out. The process of sorption of α-oxypropionic (α-oxypropionic) acid by natural zeolite of Sokyrnytsia deposit was considered. It was established that the most economically advantageous and safe is the method of adsorption using a natural sorbent - zeolite, which provides the lowest concentration of contaminants in treated wastewaters from dairies. An assessment of their number, localization features and measures of toxicological impact on the environment was done. The existing theoretical apparatus of description of adsorption processes was analyzed. The sorption properties of natural zeolite (clinoptilolite of Sokyrnytsia deposit) and activated carbon to α-oxypropionic acid were tested. Equilibrium values of adsorption capacity were calculated and corresponding isotherms at a temperature of 20 ° С were constructed. The porosity of the sorbent and its influence on the sorption properties were studied by the methods of physicochemical analysis. Infrared spectroscopic and electron microscopic studies confirmed the presence of the process of sorption by the surface of the internal pores of the zeolite of α-oxypropionic acid molecules. Experimental studies have confirmed the possibility of using natural zeolite for wastewater treatment of dairy factories. It was experimentally confirmed by physicochemical methods of analysis (electron microscopy, IR spectroscopy, microprobe analysis, mercury porometry) and was established that the process takes place both by the mechanism of ion exchange and physical adsorption. The content of carbon radicals in the zeolite matrix after the sorption process was confirmed by X-ray spectral microanalysis. The ability of zeolite to adsorb organic carboxylic acid radicals was confirmed by the results of IR spectroscopic studies. On the IR spectra there are strips of deformation and valence oscillations of the groups of the crystal lattice of the zeolite Si-O, Si-O-SiOH: 452, 990–1210, 1638, 3368 cm−1. The oscillation spectra of free OH groups in the region of 2600 cm−1 were revealed.","PeriodicalId":7327,"journal":{"name":"Advances in Materials Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87997799","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}
Abstract Thermal buckling study on the symmetric laminated composite trapezoidal plate with a circular cutout subjected to a uniform increase in temperature for various boundary conditions is explored in this paper. In a mathematical model, the first-order shear deformation principle is employed in accordance with the variational energy system. For acquiring the thermal buckling temperature, a nine-node heterosis plate relation has been used in the finite element formulation. By correlating the present findings with accessible literature, the effectiveness of the present formulation is verified. The impact of different parameters, such as trapezoidal shape, cutout size, ply-orientation, plate edge conditions and plate width to thickness ratio have been considered to study the effect of each parameters on the buckling characteristics of plate under various temperatures. It is observed from the study that each parametric investigation significantly affect the thermal buckling behaviour of trapezoidal plates.
{"title":"Effect of Trapezoidal Shapes on the Thermal Buckling Behaviour of Perforated Composite Plates","authors":"R. Maharudra, T. Rajanna, B. Arya","doi":"10.2478/adms-2021-0002","DOIUrl":"https://doi.org/10.2478/adms-2021-0002","url":null,"abstract":"Abstract Thermal buckling study on the symmetric laminated composite trapezoidal plate with a circular cutout subjected to a uniform increase in temperature for various boundary conditions is explored in this paper. In a mathematical model, the first-order shear deformation principle is employed in accordance with the variational energy system. For acquiring the thermal buckling temperature, a nine-node heterosis plate relation has been used in the finite element formulation. By correlating the present findings with accessible literature, the effectiveness of the present formulation is verified. The impact of different parameters, such as trapezoidal shape, cutout size, ply-orientation, plate edge conditions and plate width to thickness ratio have been considered to study the effect of each parameters on the buckling characteristics of plate under various temperatures. It is observed from the study that each parametric investigation significantly affect the thermal buckling behaviour of trapezoidal plates.","PeriodicalId":7327,"journal":{"name":"Advances in Materials Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75317419","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}
Abstract The paper presents research in the field of underwater wet cutting with the use of flux-cored wires in order to improve the quality and performance. The research has resulted into the development of gas and slag systems for flux-cored wires and determination of, optimal parameters for cutting stability and quality. The underwater wet cutting mechanism is a cyclical process with the formation of periodic keyholes in metal, and it consists of operating and idle cycles. Efficiency of the cutting process can be determined by analyzing cycle times, welding current, voltage, power and a number of short circuits. To assess the stability and efficiency of the underwater wet cutting process, the authors have developed the method for analyzing oscillograms to calculate the probability density of current, voltage and power. To determine the quality of cutting, the authors have provided a criterion based on the ratio of the voltage probability density in the idle and operating cycles.
{"title":"Mathematical Analysis of the Influence of the Flux-Cored Wire Chemical Composition on the Electrical Parameters and Quality in the Underwater Wet Cutting","authors":"S. Parshin, A. Levchenko, P. Wang, A. Maystro","doi":"10.2478/adms-2021-0006","DOIUrl":"https://doi.org/10.2478/adms-2021-0006","url":null,"abstract":"Abstract The paper presents research in the field of underwater wet cutting with the use of flux-cored wires in order to improve the quality and performance. The research has resulted into the development of gas and slag systems for flux-cored wires and determination of, optimal parameters for cutting stability and quality. The underwater wet cutting mechanism is a cyclical process with the formation of periodic keyholes in metal, and it consists of operating and idle cycles. Efficiency of the cutting process can be determined by analyzing cycle times, welding current, voltage, power and a number of short circuits. To assess the stability and efficiency of the underwater wet cutting process, the authors have developed the method for analyzing oscillograms to calculate the probability density of current, voltage and power. To determine the quality of cutting, the authors have provided a criterion based on the ratio of the voltage probability density in the idle and operating cycles.","PeriodicalId":7327,"journal":{"name":"Advances in Materials Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81798444","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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