Since 1989, the National Institute of Standards and Technology (NIST) Charpy Machine Verification Program in Boulder, Colorado, has been indirectly verifying Charpy machines around the world according to ASTM E23, Standard Test Methods for Notched Bar Impact Testing of Metallic Materials, and ISO 148-2, Metallic Materials-Charpy Pendulum Impact Test-Part 2: Verification of Testing Machines. Most of the indirect verifications results have been logged in a database, which at the end of May 2024 included 77,105 records, each one corresponding to 4-5 absorbed energy values at one of three energy levels (low, high, and super-high). Based on the analysis of this database, the acceptability criteria of ASTM E23, exclusively based on bias, have been compared with those of ISO 148-2, which also include repeatability. The objective of this study is to support the proposal of revising ASTM E23 by introducing repeatability requirements in addition to the existing bias criteria. Four proposals have been considered and assessed, leading to the selection of a set of repeatability limits (larger of 4 J and 15 % of certified absorbed energy) that only moderately increases the severity of the standard but, most importantly, prevents deeming machines acceptable that satisfy ASTM E23 bias but fail ISO 148-2 repeatability (approximately one sixth of all the machines verified by the NIST since 1990).
{"title":"On the Possibility of Adding a Repeatability Requirement for the Indirect Verification of Charpy Machines in ASTM E23.","authors":"Enrico Lucon","doi":"10.1520/mpc20240077","DOIUrl":"10.1520/mpc20240077","url":null,"abstract":"<p><p>Since 1989, the National Institute of Standards and Technology (NIST) Charpy Machine Verification Program in Boulder, Colorado, has been indirectly verifying Charpy machines around the world according to ASTM E23, <i>Standard Test Methods for Notched Bar Impact Testing of Metallic Materials</i>, and ISO 148-2, <i>Metallic Materials</i>-<i>Charpy Pendulum Impact Test</i>-<i>Part 2: Verification of Testing Machines</i>. Most of the indirect verifications results have been logged in a database, which at the end of May 2024 included 77,105 records, each one corresponding to 4-5 absorbed energy values at one of three energy levels (low, high, and super-high). Based on the analysis of this database, the acceptability criteria of ASTM E23, exclusively based on bias, have been compared with those of ISO 148-2, which also include repeatability. The objective of this study is to support the proposal of revising ASTM E23 by introducing repeatability requirements in addition to the existing bias criteria. Four proposals have been considered and assessed, leading to the selection of a set of repeatability limits (larger of 4 J and 15 % of certified absorbed energy) that only moderately increases the severity of the standard but, most importantly, prevents deeming machines acceptable that satisfy ASTM E23 bias but fail ISO 148-2 repeatability (approximately one sixth of all the machines verified by the NIST since 1990).</p>","PeriodicalId":18234,"journal":{"name":"Materials Performance and Characterization","volume":"14 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11984351/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144042871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Giuseppe Pintaude, Ana Sofia C. M. d’Oliveira, A. P. Tschiptschin, Filipe Fernandes
{"title":"Editorial—Special Issue on Functional Surfaces: Manufacturing, Measuring, and Performance","authors":"Giuseppe Pintaude, Ana Sofia C. M. d’Oliveira, A. P. Tschiptschin, Filipe Fernandes","doi":"10.1520/mpc20230998","DOIUrl":"https://doi.org/10.1520/mpc20230998","url":null,"abstract":"","PeriodicalId":18234,"journal":{"name":"Materials Performance and Characterization","volume":"204 ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139173983","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}
Ayodele Abraham Ajayi, Mohan Turup Pandurangan, K. Kanny, Velmurugan Ramachandran
{"title":"Thermal and Wettability Properties of Nanoclay-Filled Epoxy-Based Foam Composite as Lightweight Material","authors":"Ayodele Abraham Ajayi, Mohan Turup Pandurangan, K. Kanny, Velmurugan Ramachandran","doi":"10.1520/mpc20230085","DOIUrl":"https://doi.org/10.1520/mpc20230085","url":null,"abstract":"","PeriodicalId":18234,"journal":{"name":"Materials Performance and Characterization","volume":"50 2","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138632889","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}
J. Simsiriwong, Meysam Haghshenas, Kirk Marquard, R. K. Kersey
{"title":"Editorial: Special Issue on Very High Cycle Fatigue","authors":"J. Simsiriwong, Meysam Haghshenas, Kirk Marquard, R. K. Kersey","doi":"10.1520/mpc20230999","DOIUrl":"https://doi.org/10.1520/mpc20230999","url":null,"abstract":"","PeriodicalId":18234,"journal":{"name":"Materials Performance and Characterization","volume":"67 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139281610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effect of Stress Ratio, Constraint, and Load History on the Intrinsic and Extrinsic Components of Threshold Stress Intensity","authors":"R. Sunder, Ramesh Koraddi, Vishwas Chandra","doi":"10.1520/mpc20230078","DOIUrl":"https://doi.org/10.1520/mpc20230078","url":null,"abstract":"","PeriodicalId":18234,"journal":{"name":"Materials Performance and Characterization","volume":"93 S1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135584204","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}
Lhwan Philippe Silva, Daniel Silva de Lara, Jacobus Swart, Raluca Savu
{"title":"Optimization of PDMS Surface Treatment Using Atmospheric Pressure Plasma for Microfluidic Applications","authors":"Lhwan Philippe Silva, Daniel Silva de Lara, Jacobus Swart, Raluca Savu","doi":"10.1520/mpc20230022","DOIUrl":"https://doi.org/10.1520/mpc20230022","url":null,"abstract":"","PeriodicalId":18234,"journal":{"name":"Materials Performance and Characterization","volume":"135 21","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136106794","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}
Lauro Mariano Ferreira, Rodrigo Perito Cardoso, Ana Sofia C. M. D’Oliveira
The application of niobium borides to components such as lamination cylinders, hightemperature devices, and medical equipment shows their importance and versatility in engineering. To improve niobium’s mechanical resistance and possible oxidation resistance at temperature, this research applied boronizing to pure niobium, carried out with double pack cementation. Boronizing at 950°C and 1,100°C was carried out for 1 and 4 h. Ekabor commercial pack mixture with a nominal chemical composition of 90 % silicon carbide, 5 % boron carbide, and 5 % potassium tetrafluoroborate was used with and without 10 percent by weight (wt%) silicon addition. Scanning electron microscope, energy dispersive spectroscopy, and X-ray diffraction analyses and microhardness tests were used to characterize the treated samples. A continuous high-hardness 2,394-HV0.1 (23.5 GPa) niobium diboride layer was formed at the surface of the niobium substrate. A maximum layer thickness of 53.6 ± 2.9 µm was measured after 4 h at 1,100°C, whereas after 1 h at 950°C, no visible layer was identified with the applied characterization techniques, suggesting a threshold in this temperature. Adding 10 wt% silicon to the pack mixture impacted the kinetics of the diffusion process, which resulted in an increase in layer thickness of 72.6 ± 10.1 µm after processing for 1 h at 1,100°C, but cracks formed in the processed surface.
{"title":"Niobium Boronizing: Influence of the Treatment Temperature and Time","authors":"Lauro Mariano Ferreira, Rodrigo Perito Cardoso, Ana Sofia C. M. D’Oliveira","doi":"10.1520/mpc20220122","DOIUrl":"https://doi.org/10.1520/mpc20220122","url":null,"abstract":"The application of niobium borides to components such as lamination cylinders, hightemperature devices, and medical equipment shows their importance and versatility in engineering. To improve niobium’s mechanical resistance and possible oxidation resistance at temperature, this research applied boronizing to pure niobium, carried out with double pack cementation. Boronizing at 950°C and 1,100°C was carried out for 1 and 4 h. Ekabor commercial pack mixture with a nominal chemical composition of 90 % silicon carbide, 5 % boron carbide, and 5 % potassium tetrafluoroborate was used with and without 10 percent by weight (wt%) silicon addition. Scanning electron microscope, energy dispersive spectroscopy, and X-ray diffraction analyses and microhardness tests were used to characterize the treated samples. A continuous high-hardness 2,394-HV0.1 (23.5 GPa) niobium diboride layer was formed at the surface of the niobium substrate. A maximum layer thickness of 53.6 ± 2.9 µm was measured after 4 h at 1,100°C, whereas after 1 h at 950°C, no visible layer was identified with the applied characterization techniques, suggesting a threshold in this temperature. Adding 10 wt% silicon to the pack mixture impacted the kinetics of the diffusion process, which resulted in an increase in layer thickness of 72.6 ± 10.1 µm after processing for 1 h at 1,100°C, but cracks formed in the processed surface.","PeriodicalId":18234,"journal":{"name":"Materials Performance and Characterization","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135513828","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}
Viviane Teleginski Mazur, Letícia Batista Guimarães, Ana Sofia Clímaco Monteiro D’Oliveira
The customization of metallic alloys offers the possibility of adding functionalities to a material. Customizing alloys with a dispersion of intermetallic compounds obtained by in situ synthesis does not compromise processing and allows for the addition of functionalities to less noble alloys. However, intermetallic materials present important challenges regarding their processability by welding and forming because of low toughness, ductility, and metallurgical stability at high temperatures. Graded multilayer coatings might offer a balanced solution to the aforementioned challenges by taking advantage of a ductile matrix while the fine dispersion of aluminides reinforces hardness and metallurgical stability. This investigation addressed this challenge by processing coatings of Inconel 625 superalloy with in situ formed Ni-Al based intermetallics to increase hardness and high temperature oxidation resistance while maintaining weldability. Powder mixtures of Inconel 625, Ni, and Al elementary powders were processed as single and double-layer coatings. Inconel 625 atomized alloy was modified with a powder mixture containing 75 wt. % Ni and 25 wt. % Al. Each deposited layer had a different amount of the Ni + Al powder mixtures added to the atomized Inconel 625 alloy. The single layer coating was processed with a mixture containing Inconel 625 and 80 wt. % (Ni + Al), while the double-layer coating of the first layer was deposited with the powder mixture Inconel 625 and 20 wt. % (Ni + Al), and the second layer deposited with Inconel 625 and 80 wt. % (Ni+Al). Monel 400 substrates were used for all deposits in the study. Powder mixtures were deposited by Plasma Transferred Arc allowing the in situ synthesis of Ni-Al intermetallics without compromising weldability. For both coatings, microstructural stability was sustained until 900 °C, and at 1,100°C exposure led to some degree of oxidation, but the increased hardness due to nickel aluminides intermetallics in situ formation was sustained.
{"title":"Temperature Exposure of Single- and Double-Layer Coatings of Inconel 625 Reinforced with Ni3Al Intermetallics","authors":"Viviane Teleginski Mazur, Letícia Batista Guimarães, Ana Sofia Clímaco Monteiro D’Oliveira","doi":"10.1520/mpc20220120","DOIUrl":"https://doi.org/10.1520/mpc20220120","url":null,"abstract":"The customization of metallic alloys offers the possibility of adding functionalities to a material. Customizing alloys with a dispersion of intermetallic compounds obtained by in situ synthesis does not compromise processing and allows for the addition of functionalities to less noble alloys. However, intermetallic materials present important challenges regarding their processability by welding and forming because of low toughness, ductility, and metallurgical stability at high temperatures. Graded multilayer coatings might offer a balanced solution to the aforementioned challenges by taking advantage of a ductile matrix while the fine dispersion of aluminides reinforces hardness and metallurgical stability. This investigation addressed this challenge by processing coatings of Inconel 625 superalloy with in situ formed Ni-Al based intermetallics to increase hardness and high temperature oxidation resistance while maintaining weldability. Powder mixtures of Inconel 625, Ni, and Al elementary powders were processed as single and double-layer coatings. Inconel 625 atomized alloy was modified with a powder mixture containing 75 wt. % Ni and 25 wt. % Al. Each deposited layer had a different amount of the Ni + Al powder mixtures added to the atomized Inconel 625 alloy. The single layer coating was processed with a mixture containing Inconel 625 and 80 wt. % (Ni + Al), while the double-layer coating of the first layer was deposited with the powder mixture Inconel 625 and 20 wt. % (Ni + Al), and the second layer deposited with Inconel 625 and 80 wt. % (Ni+Al). Monel 400 substrates were used for all deposits in the study. Powder mixtures were deposited by Plasma Transferred Arc allowing the in situ synthesis of Ni-Al intermetallics without compromising weldability. For both coatings, microstructural stability was sustained until 900 °C, and at 1,100°C exposure led to some degree of oxidation, but the increased hardness due to nickel aluminides intermetallics in situ formation was sustained.","PeriodicalId":18234,"journal":{"name":"Materials Performance and Characterization","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135923030","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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