Fatigue Crack Initiation and Propagation Relation of Notched Specimens with Welded Joint Characteristics
This study focuses on predicting the fatigue life of notched specimens with geometries and microstructure representative of welded joints. It employs 26 series of fatigue tests on welded and non-welded specimens containing notches located in different material zones, including the parent material, w...
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| Format: | Article |
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MDPI AG
2022-04-01
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| Series: | Metals |
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| Online Access: | https://www.mdpi.com/2075-4701/12/4/615 |
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| author | Moritz Braun Claas Fischer Jörg Baumgartner Matthias Hecht Igor Varfolomeev |
| author_facet | Moritz Braun Claas Fischer Jörg Baumgartner Matthias Hecht Igor Varfolomeev |
| author_sort | Moritz Braun |
| collection | DOAJ |
| description | This study focuses on predicting the fatigue life of notched specimens with geometries and microstructure representative of welded joints. It employs 26 series of fatigue tests on welded and non-welded specimens containing notches located in different material zones, including the parent material, weld metal, and heat-affected zone. Overall, 351 test samples made of six structural steels are included in the present evaluation. For each individual specimen, the stress concentration factor, as well as the stress distribution in the notched section, was determined for subsequent fracture mechanics calculation. The latter is employed to estimate the fraction of fatigue life associated with crack propagation, starting from a small surface crack until fracture. It was shown that the total fatigue life can be realistically predicted by means of fracture mechanics calculations, whereas estimates of the fatigue life until macroscopic crack initiation are subject to numerous uncertainties. Furthermore, methods of statistical data analyses are applied to explore correlations between the S–N curves and the notch acuity characterized by the notch radius, opening angle, and the stress concentration factor. In particular, a strong correlation is observed between the notch acuity and the slope of the S–N curves. |
| first_indexed | 2024-03-09T10:32:10Z |
| format | Article |
| id | doaj.art-899b5335a82c42d0a4542196626b58c0 |
| institution | Directory Open Access Journal |
| issn | 2075-4701 |
| language | English |
| last_indexed | 2024-03-09T10:32:10Z |
| publishDate | 2022-04-01 |
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| series | Metals |
| spelling | doaj.art-899b5335a82c42d0a4542196626b58c02023-12-01T21:13:57ZengMDPI AGMetals2075-47012022-04-0112461510.3390/met12040615Fatigue Crack Initiation and Propagation Relation of Notched Specimens with Welded Joint CharacteristicsMoritz Braun0Claas Fischer1Jörg Baumgartner2Matthias Hecht3Igor Varfolomeev4Institute of Ship Structural Design and Analysis, Hamburg University of Technology, 21073 Hamburg, GermanyTÜV NORD EnSys GmbH & Co. KG, 22525 Hamburg, GermanyResearch Group System Reliability, Adaptive Structures Machine Acoustics SAM, Mechanical Engineering Department, Technical University of Darmstadt, 64287 Darmstadt, GermanyResearch Group System Reliability, Adaptive Structures Machine Acoustics SAM, Mechanical Engineering Department, Technical University of Darmstadt, 64287 Darmstadt, GermanyFraunhofer Institute for Mechanics of Materials, 79108 Freiburg, GermanyThis study focuses on predicting the fatigue life of notched specimens with geometries and microstructure representative of welded joints. It employs 26 series of fatigue tests on welded and non-welded specimens containing notches located in different material zones, including the parent material, weld metal, and heat-affected zone. Overall, 351 test samples made of six structural steels are included in the present evaluation. For each individual specimen, the stress concentration factor, as well as the stress distribution in the notched section, was determined for subsequent fracture mechanics calculation. The latter is employed to estimate the fraction of fatigue life associated with crack propagation, starting from a small surface crack until fracture. It was shown that the total fatigue life can be realistically predicted by means of fracture mechanics calculations, whereas estimates of the fatigue life until macroscopic crack initiation are subject to numerous uncertainties. Furthermore, methods of statistical data analyses are applied to explore correlations between the S–N curves and the notch acuity characterized by the notch radius, opening angle, and the stress concentration factor. In particular, a strong correlation is observed between the notch acuity and the slope of the S–N curves.https://www.mdpi.com/2075-4701/12/4/615notch fatigue analysisfinite element analysisfracture mechanicsstress gradientnotch acuityS–N curves |
| spellingShingle | Moritz Braun Claas Fischer Jörg Baumgartner Matthias Hecht Igor Varfolomeev Fatigue Crack Initiation and Propagation Relation of Notched Specimens with Welded Joint Characteristics Metals notch fatigue analysis finite element analysis fracture mechanics stress gradient notch acuity S–N curves |
| title | Fatigue Crack Initiation and Propagation Relation of Notched Specimens with Welded Joint Characteristics |
| title_full | Fatigue Crack Initiation and Propagation Relation of Notched Specimens with Welded Joint Characteristics |
| title_fullStr | Fatigue Crack Initiation and Propagation Relation of Notched Specimens with Welded Joint Characteristics |
| title_full_unstemmed | Fatigue Crack Initiation and Propagation Relation of Notched Specimens with Welded Joint Characteristics |
| title_short | Fatigue Crack Initiation and Propagation Relation of Notched Specimens with Welded Joint Characteristics |
| title_sort | fatigue crack initiation and propagation relation of notched specimens with welded joint characteristics |
| topic | notch fatigue analysis finite element analysis fracture mechanics stress gradient notch acuity S–N curves |
| url | https://www.mdpi.com/2075-4701/12/4/615 |
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