The New Italian Standard on the Life Assessment of Martensitic Steels—First Results of the Experimental Validation Activity of XRD by Testing P91 and P92 Samples from Interrupted Uniaxial Creep Tests
The Italian Thermotechnical Committee is drafting a new standard for the life assessment of creep-operated pressure equipment, including modern steam boilers. For the evaluation of the spent life ratio several methods are available, even if each of them is not exhaustive. It should be noted that the...
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| Language: | English |
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MDPI AG
2023-03-01
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| Series: | Micro |
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| Online Access: | https://www.mdpi.com/2673-8023/3/1/20 |
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| author | Andrea Tonti Pietro De Blasi |
| author_facet | Andrea Tonti Pietro De Blasi |
| author_sort | Andrea Tonti |
| collection | DOAJ |
| description | The Italian Thermotechnical Committee is drafting a new standard for the life assessment of creep-operated pressure equipment, including modern steam boilers. For the evaluation of the spent life ratio several methods are available, even if each of them is not exhaustive. It should be noted that the methods described must be considered in combination with NDTs and other kinds of tests, e.g., hardness tests. X-ray diffraction (XRD) is one of the methods that could be used to assess material evolution under creep conditions. The method allows for the study of phase transitions involving structural variations. It is possible to operate on both massive samples and powders. In this paper, work done with XRD, in the frame of a wider project regarding the study of the high-temperature behavior of welded martensitic steels, is presented. The results of the XRD analysis were compared with the results of the extraction replicas. This work concerns the controls of eight failed crept specimens submitted to XRD examinations. Eight XRD diagrams were produced and subsequently compared with 12 replicas for each specimen; that is, 96 extraction replicas were produced for this work. Then, around 5000 precipitates were analyzed for each specimen; therefore, for this work, around 40,000 precipitates were characterized with their chemical compositions. The average size of the precipitates was around 97 nm. |
| first_indexed | 2024-03-11T06:10:36Z |
| format | Article |
| id | doaj.art-ad8faab251394fb193ebd2ab00193cad |
| institution | Directory Open Access Journal |
| issn | 2673-8023 |
| language | English |
| last_indexed | 2024-03-11T06:10:36Z |
| publishDate | 2023-03-01 |
| publisher | MDPI AG |
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| spelling | doaj.art-ad8faab251394fb193ebd2ab00193cad2023-11-17T12:41:06ZengMDPI AGMicro2673-80232023-03-013127430710.3390/micro3010020The New Italian Standard on the Life Assessment of Martensitic Steels—First Results of the Experimental Validation Activity of XRD by Testing P91 and P92 Samples from Interrupted Uniaxial Creep TestsAndrea Tonti0Pietro De Blasi1Department of Technological Innovations and Safety of Plants, Products and Anthropic Settlements, Italian Working Compensation Authority, 00143 Roma, ItalyAdvisory Department for Health and Safety, Italian Working Compensation Authority, 00143 Roma, ItalyThe Italian Thermotechnical Committee is drafting a new standard for the life assessment of creep-operated pressure equipment, including modern steam boilers. For the evaluation of the spent life ratio several methods are available, even if each of them is not exhaustive. It should be noted that the methods described must be considered in combination with NDTs and other kinds of tests, e.g., hardness tests. X-ray diffraction (XRD) is one of the methods that could be used to assess material evolution under creep conditions. The method allows for the study of phase transitions involving structural variations. It is possible to operate on both massive samples and powders. In this paper, work done with XRD, in the frame of a wider project regarding the study of the high-temperature behavior of welded martensitic steels, is presented. The results of the XRD analysis were compared with the results of the extraction replicas. This work concerns the controls of eight failed crept specimens submitted to XRD examinations. Eight XRD diagrams were produced and subsequently compared with 12 replicas for each specimen; that is, 96 extraction replicas were produced for this work. Then, around 5000 precipitates were analyzed for each specimen; therefore, for this work, around 40,000 precipitates were characterized with their chemical compositions. The average size of the precipitates was around 97 nm.https://www.mdpi.com/2673-8023/3/1/20diffractioncreepmartensitics |
| spellingShingle | Andrea Tonti Pietro De Blasi The New Italian Standard on the Life Assessment of Martensitic Steels—First Results of the Experimental Validation Activity of XRD by Testing P91 and P92 Samples from Interrupted Uniaxial Creep Tests Micro diffraction creep martensitics |
| title | The New Italian Standard on the Life Assessment of Martensitic Steels—First Results of the Experimental Validation Activity of XRD by Testing P91 and P92 Samples from Interrupted Uniaxial Creep Tests |
| title_full | The New Italian Standard on the Life Assessment of Martensitic Steels—First Results of the Experimental Validation Activity of XRD by Testing P91 and P92 Samples from Interrupted Uniaxial Creep Tests |
| title_fullStr | The New Italian Standard on the Life Assessment of Martensitic Steels—First Results of the Experimental Validation Activity of XRD by Testing P91 and P92 Samples from Interrupted Uniaxial Creep Tests |
| title_full_unstemmed | The New Italian Standard on the Life Assessment of Martensitic Steels—First Results of the Experimental Validation Activity of XRD by Testing P91 and P92 Samples from Interrupted Uniaxial Creep Tests |
| title_short | The New Italian Standard on the Life Assessment of Martensitic Steels—First Results of the Experimental Validation Activity of XRD by Testing P91 and P92 Samples from Interrupted Uniaxial Creep Tests |
| title_sort | new italian standard on the life assessment of martensitic steels first results of the experimental validation activity of xrd by testing p91 and p92 samples from interrupted uniaxial creep tests |
| topic | diffraction creep martensitics |
| url | https://www.mdpi.com/2673-8023/3/1/20 |
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