Pub Date : 2023-10-24DOI: 10.26896/1028-6861-2023-89-10-5-11
A. V. Egoshina, G. B. Slepchenko
A high chemical resistance inherent in the alloys based on platinum group metals is one of the reasons for a number of difficulties that arise when dissolving such materials. Nowadays, the dissolution in aqua regia is one of the most effective methods for dissolving corrosion-resistant alloys. The main disadvantage of this method is a release of toxic gaseous substances such as nitrosyl chloride and nitrogen oxides. To decrease the volume of gases thus released without reducing the redox potential of the system, we proposed a method of dissolving a Pt – Rh alloy in HCl-HNO3 with a controlled dosed supply of HNO 3 at a given value of the oxidation-reduction potential (ORP) of the system. The potential of the system has been chosen proceeding from the potential for HNO 3 – HCl – Pt and HNO 3 – HCl-Rh systems and amounted to 0.85 and 0.9 V. The impact of the dispersion and the inherent flaw of PtRh alloys on the dissolution indices of the alloy was also considered. It is shown that the dissolution of a Pt – Rh alloy with a rhodium content of 15 % in HCl – HNO 3 at a constant value of ORP = 0.9 V compared to the use of the classic mixture (HCl:HNO 3 = 1:3 vol.) provides a decrease in nitric acid consumption by 40%, reduction of the process time, increase in the recovery factor for both platinum and rhodium, and a two-fold reduction of the volume of released nitrogen oxides (theoretical calculation). It is also revealed that the process of mechanical activation of the alloy reduces the dissolution time and leads to almost quantitative dissolution of the sample.
{"title":"Intensification of opening a thrust alloy based on platinum and rhodium","authors":"A. V. Egoshina, G. B. Slepchenko","doi":"10.26896/1028-6861-2023-89-10-5-11","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-10-5-11","url":null,"abstract":"A high chemical resistance inherent in the alloys based on platinum group metals is one of the reasons for a number of difficulties that arise when dissolving such materials. Nowadays, the dissolution in aqua regia is one of the most effective methods for dissolving corrosion-resistant alloys. The main disadvantage of this method is a release of toxic gaseous substances such as nitrosyl chloride and nitrogen oxides. To decrease the volume of gases thus released without reducing the redox potential of the system, we proposed a method of dissolving a Pt – Rh alloy in HCl-HNO3 with a controlled dosed supply of HNO 3 at a given value of the oxidation-reduction potential (ORP) of the system. The potential of the system has been chosen proceeding from the potential for HNO 3 – HCl – Pt and HNO 3 – HCl-Rh systems and amounted to 0.85 and 0.9 V. The impact of the dispersion and the inherent flaw of PtRh alloys on the dissolution indices of the alloy was also considered. It is shown that the dissolution of a Pt – Rh alloy with a rhodium content of 15 % in HCl – HNO 3 at a constant value of ORP = 0.9 V compared to the use of the classic mixture (HCl:HNO 3 = 1:3 vol.) provides a decrease in nitric acid consumption by 40%, reduction of the process time, increase in the recovery factor for both platinum and rhodium, and a two-fold reduction of the volume of released nitrogen oxides (theoretical calculation). It is also revealed that the process of mechanical activation of the alloy reduces the dissolution time and leads to almost quantitative dissolution of the sample.","PeriodicalId":494936,"journal":{"name":"Заводская лаборатория. Диагностика материалов","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135321819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-24DOI: 10.26896/1028-6861-2023-89-10-12-18
M. Yu. Burylin, E. S. Kopeiko, E. S. Kostyuchenko
A need to control the silver content in high-purity copper and nickel samples is attributed to the deterioration of the technical characteristics of materials when the presence of such impurities exceeds the permissible levels. In this study, modes for the determination of Ag in copper and nickel by high-resolution electrothermal atomic absorption spectrometry with a continuum source at a content of 10 –6 – 10 –5 % have been developed. The optimal temperature regimes of the atomizer program and the amount of chemical modifier introduced were developed proceeding from the results of studying the regularities of atomic absorption measurements of silver in matrix solutions of Cu and Ni (with a concentration of 10 g/liter each). To construct calibration dependences, aqueous standard solutions of the analyte (determination in copper) and aqueous standard solutions of the analyte with the addition of nickel nitrate 10 mg/liter (determination in nickel) were used. The atomization temperature was chosen to be 1600°C. The dosing volume of the solutions in the graphite furnace was always 20 μl. When determining Ag in high-purity copper, different temperatures of the pyrolysis stage were used for measurements with dosing of standard analyte solutions (600°C) and for measurements with dosing of the analyzed copper solution (800°C). In the determination of silver in nickel solutions, the temperature of the pyrolysis stage was 800°C. The developed conditions for the determination of silver were tested in the analysis of high-purity samples of copper and nickel (standard solutions of Inorganic Ventures, USA with a concentration of 10 g/liter) using spiked tests. The maximum value of the relative error of determinations does not exceed 13%. The detection limits for silver were: 1.8 × 10 –6 % in copper and 3.2 × 10 –6 % in nickel.
{"title":"Determination of Ag in high-purity solutions of copper and nickel by high-resolution continuum-source electrothermal atomic absorption spectrometry (HR-CS-ETAAS)","authors":"M. Yu. Burylin, E. S. Kopeiko, E. S. Kostyuchenko","doi":"10.26896/1028-6861-2023-89-10-12-18","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-10-12-18","url":null,"abstract":"A need to control the silver content in high-purity copper and nickel samples is attributed to the deterioration of the technical characteristics of materials when the presence of such impurities exceeds the permissible levels. In this study, modes for the determination of Ag in copper and nickel by high-resolution electrothermal atomic absorption spectrometry with a continuum source at a content of 10 –6 – 10 –5 % have been developed. The optimal temperature regimes of the atomizer program and the amount of chemical modifier introduced were developed proceeding from the results of studying the regularities of atomic absorption measurements of silver in matrix solutions of Cu and Ni (with a concentration of 10 g/liter each). To construct calibration dependences, aqueous standard solutions of the analyte (determination in copper) and aqueous standard solutions of the analyte with the addition of nickel nitrate 10 mg/liter (determination in nickel) were used. The atomization temperature was chosen to be 1600°C. The dosing volume of the solutions in the graphite furnace was always 20 μl. When determining Ag in high-purity copper, different temperatures of the pyrolysis stage were used for measurements with dosing of standard analyte solutions (600°C) and for measurements with dosing of the analyzed copper solution (800°C). In the determination of silver in nickel solutions, the temperature of the pyrolysis stage was 800°C. The developed conditions for the determination of silver were tested in the analysis of high-purity samples of copper and nickel (standard solutions of Inorganic Ventures, USA with a concentration of 10 g/liter) using spiked tests. The maximum value of the relative error of determinations does not exceed 13%. The detection limits for silver were: 1.8 × 10 –6 % in copper and 3.2 × 10 –6 % in nickel.","PeriodicalId":494936,"journal":{"name":"Заводская лаборатория. Диагностика материалов","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135316792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-24DOI: 10.26896/1028-6861-2023-89-9-82-90
V. D. Zaharchenko, R. S. Mikheev, I. E. Kalashnikov
A mathematical model for studying temperature and time conditions of the process of friction surfacing in the manufacture of functionally organized steel-aluminum compositions has been developed and validated. Bars made of pure aluminum grade ER1100 were used as the consumable rod material during friction surfacing. The substrate in the form of a rectangular plate was made of high-quality steel 20. The geometric model of the object when modeling the process of friction surfacing in the ANSYS 2021R2 software package was specified in the form of a rod and a substrate. The initial data for calculating temperature-time conditions of the friction surfacing process are: geometric parameters of the simulation object; characteristics of thermal loads of the heating source which depend on the technological parameters of the surfacing mode (the speed of axial rotation of the rod, axial pressure, boundary conditions of the simulation object for the temperature problem), and auxiliary parameters that determine the order of calculations. The thermal power arising at the point of physical contact between the rotating consumable rod and the substrate was considered a parameter of the source thermal load. The calculation of heat propagation for the friction surfacing process was carried out according to a scheme with a normally circular source located on the substrate surface. The calculation scheme directly reflects the main feature of the friction surfacing process: the introduction of heat due to friction between the rotating consumable rod and the substrate. It is shown that taking into account the boundary conditions and geometric features of the 3D model provide a satisfactory convergence of developed mathematical model and ensure the uncertainty of no more than 5 % in determining the heating temperature of the substrate when forming functional aluminum coatings, as well as composite materials on their base when surfacing them on the surface of steel substrates.
{"title":"Mathematical methods in studying temperature-time conditions of the friction surfacing in the manufacture of functionally organized steel-aluminum compositions","authors":"V. D. Zaharchenko, R. S. Mikheev, I. E. Kalashnikov","doi":"10.26896/1028-6861-2023-89-9-82-90","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-9-82-90","url":null,"abstract":"A mathematical model for studying temperature and time conditions of the process of friction surfacing in the manufacture of functionally organized steel-aluminum compositions has been developed and validated. Bars made of pure aluminum grade ER1100 were used as the consumable rod material during friction surfacing. The substrate in the form of a rectangular plate was made of high-quality steel 20. The geometric model of the object when modeling the process of friction surfacing in the ANSYS 2021R2 software package was specified in the form of a rod and a substrate. The initial data for calculating temperature-time conditions of the friction surfacing process are: geometric parameters of the simulation object; characteristics of thermal loads of the heating source which depend on the technological parameters of the surfacing mode (the speed of axial rotation of the rod, axial pressure, boundary conditions of the simulation object for the temperature problem), and auxiliary parameters that determine the order of calculations. The thermal power arising at the point of physical contact between the rotating consumable rod and the substrate was considered a parameter of the source thermal load. The calculation of heat propagation for the friction surfacing process was carried out according to a scheme with a normally circular source located on the substrate surface. The calculation scheme directly reflects the main feature of the friction surfacing process: the introduction of heat due to friction between the rotating consumable rod and the substrate. It is shown that taking into account the boundary conditions and geometric features of the 3D model provide a satisfactory convergence of developed mathematical model and ensure the uncertainty of no more than 5 % in determining the heating temperature of the substrate when forming functional aluminum coatings, as well as composite materials on their base when surfacing them on the surface of steel substrates.","PeriodicalId":494936,"journal":{"name":"Заводская лаборатория. Диагностика материалов","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135925164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-24DOI: 10.26896/1028-6861-2023-89-9-41-47
V. F. Novikov, S. M. Kulak, K. R. Muratov, V. V. Probotyuk
To improve the accuracy of determining mechanical stresses in steel by the method of magnetoelastic demagnetization (magnetoelastic memory), the magnetoelastic sensitivity of the material to elastic stresses is additionally measured by applying or removing an additional load of a known value. We present the results of studying the magnetoelastic demagnetization of locally magnetized steel by varying stresses of the uniaxial tension or compression against a background of the base load. The magnetoelastic sensitivity of the steel in a loaded state to variable stresses has been assessed. It is shown that the determination of the magnetoelastic sensitivity of the steel to variable loads makes it possible to improve the accuracy of estimating base stresses in the steel structure using magnetoelastic methods. It is revealed that a decrease in the strength of the magnetic scattering field of the local residual magnetization (LRM) of the steel after variable loading (or unloading) exponentially depends on the magnitude of the base stresses. The possibility of controlling the uniaxial mechanical stresses in steel structures in the magnetoelastic memory mode which is based on the dependence of the strength of magnetic scattering field of the local residual magnetization of the steel on the uniaxial stresses is shown. A method for monitoring uniaxial stresses in the elements of steel structures by the method of magnetoelastic memory is proposed using the measured magnetoelastic sensitivity of the material. The results obtained can be used in the development of a method for monitoring the stress-strain state of steel structures during operation under the simultaneous effect of static and dynamic loads.
{"title":"Study of magnetoelastic demagnetization of locally magnetized steel","authors":"V. F. Novikov, S. M. Kulak, K. R. Muratov, V. V. Probotyuk","doi":"10.26896/1028-6861-2023-89-9-41-47","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-9-41-47","url":null,"abstract":"To improve the accuracy of determining mechanical stresses in steel by the method of magnetoelastic demagnetization (magnetoelastic memory), the magnetoelastic sensitivity of the material to elastic stresses is additionally measured by applying or removing an additional load of a known value. We present the results of studying the magnetoelastic demagnetization of locally magnetized steel by varying stresses of the uniaxial tension or compression against a background of the base load. The magnetoelastic sensitivity of the steel in a loaded state to variable stresses has been assessed. It is shown that the determination of the magnetoelastic sensitivity of the steel to variable loads makes it possible to improve the accuracy of estimating base stresses in the steel structure using magnetoelastic methods. It is revealed that a decrease in the strength of the magnetic scattering field of the local residual magnetization (LRM) of the steel after variable loading (or unloading) exponentially depends on the magnitude of the base stresses. The possibility of controlling the uniaxial mechanical stresses in steel structures in the magnetoelastic memory mode which is based on the dependence of the strength of magnetic scattering field of the local residual magnetization of the steel on the uniaxial stresses is shown. A method for monitoring uniaxial stresses in the elements of steel structures by the method of magnetoelastic memory is proposed using the measured magnetoelastic sensitivity of the material. The results obtained can be used in the development of a method for monitoring the stress-strain state of steel structures during operation under the simultaneous effect of static and dynamic loads.","PeriodicalId":494936,"journal":{"name":"Заводская лаборатория. Диагностика материалов","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135925341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-24DOI: 10.26896/1028-6861-2023-89-9-25-33
V. G. Amelin, Z. A.Ch. Shogah, D. S. Bolshakov, A. V. Tretyakov, I. S. Nesterenko, L. K. Kish
A simple and affordable colorimetric procedure for determination of the seafood spoilage (e.g., shrimp, squid, catfish and herring) using a smartphone and chemometric analysis is considered. The proposed colorimetric sensor consists of 12 zones, i.e., disks of cellulose paper 4 mm in diameter impregnated with acid-base indicators with a color change in the pH range of 3 – 8.8. Spoiling of the seafood is accompanied with a release of volatile biogenic amines that change the color of the indicator zones. A device and a method for measuring the colorimetric parameters of a test system using a smartphone as a recording device equipped with a specialized RGBer product are described. Processing of the data array (the sum of the R, G, and B channel values for each indicator, or the R, G, and B values for individual indicators) was performed using the XLSTAT software. Patterns of the degradation of food products identified in the study made it possible to propose a method for assessing the quality of seafood in real time. The optimal time regime of heat treatment of the sample was determined, which is necessary for the isolation of biogenic amines and the formation of an analytical signal. The parameters for identification of the seafood spoilage are the values of the main component F1 (or the position of the images on the canonical function projection graph) after evaluating the colorimetric data using the principal component method. The results obtained with a colorimetric sensor match the data for determination of the total microbial number of the analyzed products. The considered method for assessing spoilage of the seafood is distinguished by the simplicity of hardware design, the availability of the materials and software resources used, the rapidity of the procedure, and the mobility of the means for recording the analytical signal.
{"title":"Determination of seafood spoilage by digital colorimetry of indicator test systems","authors":"V. G. Amelin, Z. A.Ch. Shogah, D. S. Bolshakov, A. V. Tretyakov, I. S. Nesterenko, L. K. Kish","doi":"10.26896/1028-6861-2023-89-9-25-33","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-9-25-33","url":null,"abstract":"A simple and affordable colorimetric procedure for determination of the seafood spoilage (e.g., shrimp, squid, catfish and herring) using a smartphone and chemometric analysis is considered. The proposed colorimetric sensor consists of 12 zones, i.e., disks of cellulose paper 4 mm in diameter impregnated with acid-base indicators with a color change in the pH range of 3 – 8.8. Spoiling of the seafood is accompanied with a release of volatile biogenic amines that change the color of the indicator zones. A device and a method for measuring the colorimetric parameters of a test system using a smartphone as a recording device equipped with a specialized RGBer product are described. Processing of the data array (the sum of the R, G, and B channel values for each indicator, or the R, G, and B values for individual indicators) was performed using the XLSTAT software. Patterns of the degradation of food products identified in the study made it possible to propose a method for assessing the quality of seafood in real time. The optimal time regime of heat treatment of the sample was determined, which is necessary for the isolation of biogenic amines and the formation of an analytical signal. The parameters for identification of the seafood spoilage are the values of the main component F1 (or the position of the images on the canonical function projection graph) after evaluating the colorimetric data using the principal component method. The results obtained with a colorimetric sensor match the data for determination of the total microbial number of the analyzed products. The considered method for assessing spoilage of the seafood is distinguished by the simplicity of hardware design, the availability of the materials and software resources used, the rapidity of the procedure, and the mobility of the means for recording the analytical signal.","PeriodicalId":494936,"journal":{"name":"Заводская лаборатория. Диагностика материалов","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135924158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-24DOI: 10.26896/1028-6861-2023-89-9-13-24
A. V. Sorokin
Glyphosate is a popular herbicide often used for desiccation of crops. The use of glyphosate-based chemicals leads to the contamination of agricultural products, soils, surface and groundwater. For safety control of raw materials of the plant origin and environmental objects, a technique based on the tandem chromato-mass-spectrometry was developed to provide for the quantitative determination of glyphosate and aminomethylphosphonic acid (AMPA) without prior derivatization. The technique is characterized by a relatively simple and cost-effective sample preparation procedure. The compounds are extracted from plant raw materials with an acetic acid solution of methanol in water, in the presence of 2-aqueous disodium salt of ethylenediamine-N,N,N’,N’-tetraacetic acid (EDTA-Na 2 ) and dichloromethane. Extraction of analytes from water samples is carried out in the presence of EDTA-Na 2 and acetic acid; whereas their extraction from soil samples is carried out with a weak solution of ammonia. The extracts are purified by solid phase extraction (SPE), and proteins are precipitated with acetonitrile. Linear-dynamic ranges of glyphosate and AMPA determination are characterized by calibration curves with correlation coefficients ( R ) ≥0.99. The working range of glyphosate and AMPA determination in raw materials of plant origin was from 0.1 to 5.0 mg/kg; in surface and ground water from 0.001 to 0.05 mg/liter (glyphosate) and from 0.002 to 0.05 mg/liter (AMPA); in soils from 0.02 to 0.8 mg/kg (glyphosate) and from 0.04 to 0.8 mg/kg (AMPA). The values of the relative standard deviation range from 1.8 to 19.5%, with recovery levels ranging from 80.5 to 108.1%. The achieved values of the determination limits are consistent with the maximum permissible levels indicated in TR CU 015/2011 and SanPiN 1.2.3685–21.
{"title":"Direct determination of glyphosate and its metabolite in the plant raw material and environmental objects by chromatography-mass spectrometry","authors":"A. V. Sorokin","doi":"10.26896/1028-6861-2023-89-9-13-24","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-9-13-24","url":null,"abstract":"Glyphosate is a popular herbicide often used for desiccation of crops. The use of glyphosate-based chemicals leads to the contamination of agricultural products, soils, surface and groundwater. For safety control of raw materials of the plant origin and environmental objects, a technique based on the tandem chromato-mass-spectrometry was developed to provide for the quantitative determination of glyphosate and aminomethylphosphonic acid (AMPA) without prior derivatization. The technique is characterized by a relatively simple and cost-effective sample preparation procedure. The compounds are extracted from plant raw materials with an acetic acid solution of methanol in water, in the presence of 2-aqueous disodium salt of ethylenediamine-N,N,N’,N’-tetraacetic acid (EDTA-Na 2 ) and dichloromethane. Extraction of analytes from water samples is carried out in the presence of EDTA-Na 2 and acetic acid; whereas their extraction from soil samples is carried out with a weak solution of ammonia. The extracts are purified by solid phase extraction (SPE), and proteins are precipitated with acetonitrile. Linear-dynamic ranges of glyphosate and AMPA determination are characterized by calibration curves with correlation coefficients ( R ) ≥0.99. The working range of glyphosate and AMPA determination in raw materials of plant origin was from 0.1 to 5.0 mg/kg; in surface and ground water from 0.001 to 0.05 mg/liter (glyphosate) and from 0.002 to 0.05 mg/liter (AMPA); in soils from 0.02 to 0.8 mg/kg (glyphosate) and from 0.04 to 0.8 mg/kg (AMPA). The values of the relative standard deviation range from 1.8 to 19.5%, with recovery levels ranging from 80.5 to 108.1%. The achieved values of the determination limits are consistent with the maximum permissible levels indicated in TR CU 015/2011 and SanPiN 1.2.3685–21.","PeriodicalId":494936,"journal":{"name":"Заводская лаборатория. Диагностика материалов","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135924332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-24DOI: 10.26896/1028-6861-2023-89-9-73-81
N. Yu. Podzhivotov
The results of a comparative analysis of statistical indicators for assessing the proficiency determined during interlaboratory comparison tests (ICT) are presented. The main statistical indicators were selected: the assigned value, standard deviation for assessment the proficiency and standard uncertainty of the assigned value. Statistical indicators were determined in accordance with Algorithm A, GOST R 50779.60. Comparison of the indicators was carried out on the basis of numerical experiment data (random number generation) for the ultimate tensile strength of a D16AT aluminum alloy depending on the number of samples and the number of participants in the ICT qualification program. The calculation and subsequent statistical analysis of the proficiency test scores was based on the values generated by the software. Random number generation is performed for a characteristic that has a normal distribution law with the parameters of the mean equal to 450 MPa and standard deviation equal to 5 MPa. The values of the normal distribution parameters chosen as an example corresponded to the average level of tensile strength values of standard specimens made of D16AT aluminum alloy sheets. The numerical experiment (generation of random values) was carried out for given cases of the number of participants and the number of proficiency testing samples (PTS) independently of each other using separate samples of the appropriate size. A total of 36,000 ultimate tensile strength values were generated for the proficiency testing samples made of D16AT aluminum alloy sheets. As a result of calculations, 48 average values were determined (according to the number of considered implementations of ICT programs, depending on the number of participants and the proficiency testing samples) for each selected statistical indicator of the ICT qualification program. The average value of each statistical indicator was determined on samples with a bulk of 250 to 2000 generated (experimental) values, depending on the number of participants and the number of proficiency testing samples. The analysis thus performed made it possible to evaluate the influence of the volume of tests and the number of participants on the assessment of the proficiency in interlaboratory comparative tests. It is shown that for the selected range of the number of ICT participants (from 5 to 20) and the number of PTS (from 5 to 10), the value of the assigned x pt value does not depend either on the number of tested PTS or the number of ICT participants. The maximum discrepancy between the assigned value and the given level of tensile strength (450 MPa) is 0.13%, which falls within the error (rounding) for this level of values and cannot lead to significant errors in proficiency testing during ICT. The standard deviation for the qualification assessment, regardless of the number of participants, decreases with an increase in the number of proficiency testing samples, but such a decrease is insignificant an
{"title":"The effect of the volume of tests and the number of participants on the assessment of qualification in interlaboratory comparison tests","authors":"N. Yu. Podzhivotov","doi":"10.26896/1028-6861-2023-89-9-73-81","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-9-73-81","url":null,"abstract":"The results of a comparative analysis of statistical indicators for assessing the proficiency determined during interlaboratory comparison tests (ICT) are presented. The main statistical indicators were selected: the assigned value, standard deviation for assessment the proficiency and standard uncertainty of the assigned value. Statistical indicators were determined in accordance with Algorithm A, GOST R 50779.60. Comparison of the indicators was carried out on the basis of numerical experiment data (random number generation) for the ultimate tensile strength of a D16AT aluminum alloy depending on the number of samples and the number of participants in the ICT qualification program. The calculation and subsequent statistical analysis of the proficiency test scores was based on the values generated by the software. Random number generation is performed for a characteristic that has a normal distribution law with the parameters of the mean equal to 450 MPa and standard deviation equal to 5 MPa. The values of the normal distribution parameters chosen as an example corresponded to the average level of tensile strength values of standard specimens made of D16AT aluminum alloy sheets. The numerical experiment (generation of random values) was carried out for given cases of the number of participants and the number of proficiency testing samples (PTS) independently of each other using separate samples of the appropriate size. A total of 36,000 ultimate tensile strength values were generated for the proficiency testing samples made of D16AT aluminum alloy sheets. As a result of calculations, 48 average values were determined (according to the number of considered implementations of ICT programs, depending on the number of participants and the proficiency testing samples) for each selected statistical indicator of the ICT qualification program. The average value of each statistical indicator was determined on samples with a bulk of 250 to 2000 generated (experimental) values, depending on the number of participants and the number of proficiency testing samples. The analysis thus performed made it possible to evaluate the influence of the volume of tests and the number of participants on the assessment of the proficiency in interlaboratory comparative tests. It is shown that for the selected range of the number of ICT participants (from 5 to 20) and the number of PTS (from 5 to 10), the value of the assigned x pt value does not depend either on the number of tested PTS or the number of ICT participants. The maximum discrepancy between the assigned value and the given level of tensile strength (450 MPa) is 0.13%, which falls within the error (rounding) for this level of values and cannot lead to significant errors in proficiency testing during ICT. The standard deviation for the qualification assessment, regardless of the number of participants, decreases with an increase in the number of proficiency testing samples, but such a decrease is insignificant an","PeriodicalId":494936,"journal":{"name":"Заводская лаборатория. Диагностика материалов","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135924151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-24DOI: 10.26896/1028-6861-2023-89-9-34-40
A. S. Kolyanova
A lot of the properties polycrystalline materials depend on their crystallographic texture. The most complete information about the texture can be obtained from the orientation distribution function (ODF). We present the results of recovering ODF using series expansion technique for materials with low crystal and sample symmetry. The technique of ODF restoration is based on its Fourier series expansion with symmetrical spherical harmonic functions. Real spherical harmonics which are linear combinations of general spherical harmonics were used. The model single-component texture as well as the real texture of magnesium alloy sample subjected to equal-channel angular pressing have been studied. Textures are characterized by hexagonal crystal symmetry and triclinic sample symmetry. In both cases RP-factors and ODF calculation errors that were used as reliability criteria of ODF reconstruction showed good agreement between the calculated and experimental data. It was also revealed that the ODF of a magnesium alloy sample subjected to equal-channel angular pressing contains two texture components (1216)[1211] and (1216)[1211] with maximum intensity values of 13.81 and 2.23, respectively. The results obtained can be used for texture studies of ceramics, rocks and other non-metallic materials characterized by a lower symmetry.
{"title":"Restoration of the orientation distribution function for materials with low lattice and sample symmetry using the harmonic method","authors":"A. S. Kolyanova","doi":"10.26896/1028-6861-2023-89-9-34-40","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-9-34-40","url":null,"abstract":"A lot of the properties polycrystalline materials depend on their crystallographic texture. The most complete information about the texture can be obtained from the orientation distribution function (ODF). We present the results of recovering ODF using series expansion technique for materials with low crystal and sample symmetry. The technique of ODF restoration is based on its Fourier series expansion with symmetrical spherical harmonic functions. Real spherical harmonics which are linear combinations of general spherical harmonics were used. The model single-component texture as well as the real texture of magnesium alloy sample subjected to equal-channel angular pressing have been studied. Textures are characterized by hexagonal crystal symmetry and triclinic sample symmetry. In both cases RP-factors and ODF calculation errors that were used as reliability criteria of ODF reconstruction showed good agreement between the calculated and experimental data. It was also revealed that the ODF of a magnesium alloy sample subjected to equal-channel angular pressing contains two texture components (1216)[1211] and (1216)[1211] with maximum intensity values of 13.81 and 2.23, respectively. The results obtained can be used for texture studies of ceramics, rocks and other non-metallic materials characterized by a lower symmetry.","PeriodicalId":494936,"journal":{"name":"Заводская лаборатория. Диагностика материалов","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135924334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-24DOI: 10.26896/1028-6861-2023-89-9-48-52
R. Younes, M. Bournane, A. Idir, I. Bouklouche, M. A. Bradai, A. Sadeddine
Although used and studied since the beginning of the century, the mechanical properties of aluminum-based structural hardening alloys still conceal some secrets that metallurgists are trying to uncover. In this work we are interested in aluminum alloys and more particularly in an Al-Cu alloy. The main objective of this work was to study the influence of structural hardening heat treatments on the evolution of the mechanical and structural properties of B206 alloys. For that, we used several experimental methods adapted to this kind of scientific work. We quote essentially: the thermal treatments of setting in hardening, as well as measurements of the hardness. The analysis of the experimental results obtained by these methods allowed us to explain and to affirm that Al-Cu alloys do not give appreciable structural hardening; because of the difficulty of diffusion of iron and silicon which influences the treatment and brought in a general way to the precipitation of the phase β; plays an important role in the evolution of the mechanical characteristics of Al-Cu alloys.
{"title":"Influence of the iron additive on the microstructural behavior of an aluminum-copper foundry alloy B206","authors":"R. Younes, M. Bournane, A. Idir, I. Bouklouche, M. A. Bradai, A. Sadeddine","doi":"10.26896/1028-6861-2023-89-9-48-52","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-9-48-52","url":null,"abstract":"Although used and studied since the beginning of the century, the mechanical properties of aluminum-based structural hardening alloys still conceal some secrets that metallurgists are trying to uncover. In this work we are interested in aluminum alloys and more particularly in an Al-Cu alloy. The main objective of this work was to study the influence of structural hardening heat treatments on the evolution of the mechanical and structural properties of B206 alloys. For that, we used several experimental methods adapted to this kind of scientific work. We quote essentially: the thermal treatments of setting in hardening, as well as measurements of the hardness. The analysis of the experimental results obtained by these methods allowed us to explain and to affirm that Al-Cu alloys do not give appreciable structural hardening; because of the difficulty of diffusion of iron and silicon which influences the treatment and brought in a general way to the precipitation of the phase β; plays an important role in the evolution of the mechanical characteristics of Al-Cu alloys.","PeriodicalId":494936,"journal":{"name":"Заводская лаборатория. Диагностика материалов","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135924496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-24DOI: 10.26896/1028-6861-2023-89-9-53-63
A. M. Pokrovskii, Yu. G. Matvienko, M. P. Egranov
A methodology for evaluating the durability of plate elements of structures taking into account biaxial constraints of deformations along the front of a normal rupture crack (Mode I crack) is presented. The absence of the available literature data in which the prediction of the crack growth is carried out using T xx - and T zz -stresses which are non-singular terms in the Williams expansion for stresses at the crack tip is noted. The calculation of the fatigue crack growth rate is based on the Paris equation in which the range of the effective SIF is used instead of the range of the usual stress intensity factor (SIF). In this case, the expression for the effective SIF includes T xx - and T zz -stresses in addition to the usual SIF. This approach provides taking into account, for example, the thickness of the plate for predicting the durability, which is impossible when only the SIF and T xx -stresses are used. The formula for the effective SIF is derived proceeding from the assumption that tangential stresses in the pre-fracture zone are equal to the local strength of the material. In this case, the size of the pre-fracture zone and the local strength of the material are determined taking into account T xx - and T zz -stresses. The numerical simulation is based on the proprietary finite-element program which allows calculating T xx - and T zz -stresses at the front of a through crack in a plate subjected to cyclic uniaxial and biaxial tension. It is shown that nonsingular T xx -stresses primarily describe the effect of biaxial loading on the survivability, whereas T zz -stresses describe the effect of the plate thickness on the survivability. It is shown that with increasing thic kness of the plate the value of the effective SIF increases due to the increased constraint along the crack front, thus increasing the crack growth rate and decreasing the survivability. With an increase in the stress ratio R , under the condition of a constant stress range, the maximum effective SIF reaches the critical value equal to the fracture toughness much faster thus reducing the durability. It is shown that for uniaxial cyclic tension, the durability predicted by the proposed methodology is higher than that in the classical approach, when the conventional SIF is used in the Paris equation. For biaxial cyclic tension of a plate, an increase in stresses directed parallel to the crack banks leads to an increase of crack front constraints and therefore to a decrease in the durability compared to the classical approach. In other words, the classical theory does not always provide a conservative estimate of the durability, which indicates the expediency of using the developed method for calculating the durability taking into account biaxial constraints of deformations along the crack front.
{"title":"Prediction of the durability of a plate with a through crack taking into account biaxial constraints of deformations along the front of a normal rupture crack","authors":"A. M. Pokrovskii, Yu. G. Matvienko, M. P. Egranov","doi":"10.26896/1028-6861-2023-89-9-53-63","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-9-53-63","url":null,"abstract":"A methodology for evaluating the durability of plate elements of structures taking into account biaxial constraints of deformations along the front of a normal rupture crack (Mode I crack) is presented. The absence of the available literature data in which the prediction of the crack growth is carried out using T xx - and T zz -stresses which are non-singular terms in the Williams expansion for stresses at the crack tip is noted. The calculation of the fatigue crack growth rate is based on the Paris equation in which the range of the effective SIF is used instead of the range of the usual stress intensity factor (SIF). In this case, the expression for the effective SIF includes T xx - and T zz -stresses in addition to the usual SIF. This approach provides taking into account, for example, the thickness of the plate for predicting the durability, which is impossible when only the SIF and T xx -stresses are used. The formula for the effective SIF is derived proceeding from the assumption that tangential stresses in the pre-fracture zone are equal to the local strength of the material. In this case, the size of the pre-fracture zone and the local strength of the material are determined taking into account T xx - and T zz -stresses. The numerical simulation is based on the proprietary finite-element program which allows calculating T xx - and T zz -stresses at the front of a through crack in a plate subjected to cyclic uniaxial and biaxial tension. It is shown that nonsingular T xx -stresses primarily describe the effect of biaxial loading on the survivability, whereas T zz -stresses describe the effect of the plate thickness on the survivability. It is shown that with increasing thic kness of the plate the value of the effective SIF increases due to the increased constraint along the crack front, thus increasing the crack growth rate and decreasing the survivability. With an increase in the stress ratio R , under the condition of a constant stress range, the maximum effective SIF reaches the critical value equal to the fracture toughness much faster thus reducing the durability. It is shown that for uniaxial cyclic tension, the durability predicted by the proposed methodology is higher than that in the classical approach, when the conventional SIF is used in the Paris equation. For biaxial cyclic tension of a plate, an increase in stresses directed parallel to the crack banks leads to an increase of crack front constraints and therefore to a decrease in the durability compared to the classical approach. In other words, the classical theory does not always provide a conservative estimate of the durability, which indicates the expediency of using the developed method for calculating the durability taking into account biaxial constraints of deformations along the crack front.","PeriodicalId":494936,"journal":{"name":"Заводская лаборатория. Диагностика материалов","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135924157","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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