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Simulations of fatigue crack propagation in friction stir welds under flight loading conditions*

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Published/Copyright: May 28, 2013
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Materials Testing
From the journal Materials Testing Volume 48 Issue 7-8

Abstract

Since Friction Stir Welding has been identified as a key technology for primary aerospace structures, fatigue crack growth testing and modelling is required. However, there is still a complete lack of information regarding the fatigue crack propagation in friction stir welds under variable amplitude loading and flight loading conditions. Experimental investigations have been performed on centre cracked 4 mm thick AA2024-T3 base metal and FSW specimens: regarding the FSW samples, the crack was placed 5 mm out of the weld centre, in the most critical part of the joint: the coupons have been tested under simple variable amplitude load sequences, and under a standardized flight-simulation load history, Falstaff. The fatigue crack propagation was then predicted using widespread aerospace fracture mechanics software packages. Interaction effects and internal residual stresses were firstly separately simulated and than combined in order to evaluate the ability to predict the fatigue crack propagation on FSW welded structures under service loading conditions.

Kurzfassung

Da sich das Reibrührschweißen als Schlüsseltechnologie für primäre Luftfahrtstrukturen erwiesen hat, sind Versuche und Modelle für den Ermüdungsrissfortschritt erforderlich. Allerdings gibt es nach wie vor einen Informationsmangel bei dem Ermüdungsrisswachstum in FSW-Bauteile unter variierender Last, sowohl bei einfacher Amplitudenvariation, als auch unter Flugbedingungen. Die experimentellen Untersuchungen wurden an 4mm dicken AA2024-T3 Basismetall- und FSW-Proben durchgeführt, welche mit einem zentralen Riss versehen waren. Bei den FSW Proben wurde der Riss 5mm außerhalb der Schweißnahtmitte, im kritischsten Bereich der Fügung, plaziert. Alle Coupons sind unter Lastsequenzen mit variierender Amplitude und unter einer standardisierten Flugsimulationssequenz Falstaff geprüft worden. Der Ermüdungsrissfortschritt wurde anschließend mit Hilfe der weit verbreiteten Luftfahrt-Bruchmechanik Softwarepakete vorausgesagt. Variable Belastungen und schweißnahtbedingte Eigenspannungen wurden identifiziert und zuerst getrennt von einander simuliert. Die einzelnen Lösungen wurden dann überlagert, um das Ermüdungsrisswachstum von größeren FSW-Proben unter komplexen Lastspektren und Flugsimulation abzuschätzen.

*

Work performed during the staying of the authors at the Institute of Materials Research, German Aerospace Center, Cologne Germany. This contribution was already published in German in the DVM-Report 132 – Joining and Fatigue.

Tommaso Ghidini was born in Fidenza, Italy, in 1974. He received his M. Sc. Degree in Engineering Mechanics from the Parma University in 2000. He worked at the German Aerospace Centre of Cologne, at the Institute of Materials Research. His work was focused on fatigue, fracture mechanics and numerical simulations of welded and not-welded structures. From June 2005 he works with Airbus Germany at the Fatigue and Damage Tolerance Department. In 2006 Mr. Ghidini received a Ph. D. in Engineering Mechanics from the Paderborn University.

Claudia Polese was born in Cecina, Italy, in 1974. She received her M. Sc. Degree in Aeronautical Engineering from the Pisa University in 2001. She's now working in research activities regarding integral structures for aeropace applications at the Department of Aerospace Engineering of the University of Pisa.

Agostino Lanciotti was born in Spoleto in 1949. He's full Professor of Structural Aerospace Technology at the Department of Aerospace Engineering of the University of Pisa.

Claudio Dalle Donne was born in Karlsruhe, Germany, in 1965. He received his Ph. D. in Engineering Mechanics from the Karlsruhe University in 1996. He worked at the German Aerospace Centre of Cologne, at the Institute of Materials Research and was responsible for the research projects on fatigue and fracture mechanics as well as on friction stir welding. Since 2004 Dr. Dalle Donne has been Senior Manager Metallic Structures at the EADS Corporate Research Center in Germany.

References

1 ThomasW. M.: Friction Stir Butt Welding, International Patent Application No. 9125978.8 (1991)Search in Google Scholar

2 Christner, B.; McCoury, J.; Higgins, S.: Development and Testing of Friction Stir Welding (FSW) as a Joining Method for Primary Aircraft Structure, 4th International Symposium on Friction Stir Welding, Park City, Utah (2003)Search in Google Scholar

3 Sheperd, G. E.: The Evaluation of Friction Stir Welded Joints on Airbus Aircraft Wing Structure, 4th International Symposium on Friction Stir Welding, Park City, Utah (2003)Search in Google Scholar

4 Lohwasser, D.: Application of Friction Stir Welding for Aircraft Industry, 2th International Symposium on Friction Stir Welding, Gothenburg, Sweden, (2000)Search in Google Scholar

5 Skorupa, M.: Load Interaction Effects During Fatigue Crack Growth Under Variable Amplitude Loading-A Literature Review, Part I: Empirical Trends, Fatigue and Fracture of Engineering Materials and Structures21 (1998), pp. 987–1006Search in Google Scholar

6 Skorupa, M.: Load Interaction Effects During Fatigue Crack Growth Under Variable Amplitude Loading-A Literature Review, Part II: Qualitative Interpratation. Fatigue and Fracture of Engineering Materials and Structures, 22 (1998), pp. 905–926Search in Google Scholar

7 Masubuchi, K.: Residual Stresses and Distortion in Welded Aluminum Structures and their Effects on Service Performance, Welding Research Council Bulletins172 (1972), pp. 1–30.Search in Google Scholar

8 Dalle Donne, C.; Biallas, G.; Ghidini, T.; Raimbeaux, G.: Effect of Weld Imperfections and Residual Stresses on the Fatigue Crack Propagation in Friction Stir Welded Joints, 2th International Conference on Friction Stir Welding, Gothenburg, Sweden (2000)Search in Google Scholar

9 Dalle Donne, C.; Lima, E.; Wegener, J.; Pizalla, A.; Buslaps, T.: Investigations on Residual Stresses in Frciction Stir Welds. 3th International Conference on Friction Stir Welding, Kobe, Japan (2001)Search in Google Scholar

10 Dalle Donne, C.; Wegener, J.; Pyzalla, A.; Buslaps, T.: Investigations on Residual Stresses in Friction Stir Welds, 3th International Conference on Friction Stir Welding, Kobe, Japan (2001)Search in Google Scholar

11 Ghidini, T.; Vugrin, T.; Dalle Donne, C.: Residual Stresses, Defects and Non-Destructive Evaluation of FSW Joints, Welding International19 (2004), No. 10, pp. 783–79010.1533/wint.2005.3493Search in Google Scholar

12 FALSTAFF, Descripiton of a Fighter Loading Standard for Fatigue Evaluation. Combined Report LBF, NLR, IABG and F&W (1976)Search in Google Scholar

13 Zhang, S.; MarissenR.; Schulte, K.; Trautmann, K. H.; Nowack, H.; Schijve, J.: Crack Propagation Studies on Al 7475 on the Basis of Constant Amplitude and Selective Variable Amplitude Loading Histories, atigue and Fracture of Engineering Materials and Structures10 (1987), No. 4, pp. 312–33210.1111/j.1460-2695.1987.tb00210.xSearch in Google Scholar

14 Bachmann, V.; Marci, G.; Sengenbusch, P.: Procedure for Automated Tests of Fatigue Crack Propagation, ASTM STP1231 (1992), pp. 146–16310.1520/STP13947SSearch in Google Scholar

15 Cheng, W.; Finnie, I.: Measurement of Residual Hoop Stresses in Cylinders Using the Compliance Method, Journal of Engineering Materials Tech.108 (1986), pp. 87–9210.1115/1.3225864Search in Google Scholar

16 Schindler, H.-J.; Finnie, I.: Determination of Residual Stresses and the Resulting Stress Intensity Factors in the Ligament of Pre-Cracked Components, Proceedings 9th International Conference on Fracture, Sidney, (1997), Vol. 1, pp. 523–530Search in Google Scholar

17 Prime, M. B.: Residual Stress Measurement by Successive Extension of a Slot: the Crack Compliance Method, Applied Mechanics Reviews52 (1999), No. 2, pp. 75–9610.1115/1.3098926Search in Google Scholar

18 Chiarelli, M., A.Lanciotti, M.Sacchi: Fatigue Resistance of MAG Welded Elements. International Journal of Fatigue21 (1999), pp. 1099–111010.1016/S0142-1123(99)00080-8Search in Google Scholar

19 Harter, J. A.: Afgrow, User′s Guide and Technical Manual, AFRL-VA-WP-TR-2002-XXXX (2002)Search in Google Scholar

20 Forman, R. G.; Shivakumar, V.; Mettu, S. R.; Newman, J. C.: Fatigue Crack Growth Computer Program „Nasgro“ Version 3, JSC-22267B (2000)Search in Google Scholar

21 Ghidini, T.; Alfaro, U.; Dalle Donne, C.: Fatigue Life of Friction Stir Welded Joints in Presence of Corrosion Damage: Experiments and Calculations, Materialprüfung (Material Testing)47 (2005), No. 7–8, pp. 456–461Search in Google Scholar

22 Ghidini, T.; Dalle Donne, C.: Prediction of Fatigue Crack Propagation in Friction Stir Welds, 4th International Conference on Friction Stir Welding, Park City, Utah (2003)Search in Google Scholar

23 Forman, R. G.; Mettu, S. R.: Behavior of Surface and Corner Cracks Subjected to Tensile and Bending Loads in Ti-6-Al-4V Alloy, Fracture Mechanics 22th Symposium, ASTM STP 1131 (1992)Search in Google Scholar

24 Feddersen, C. E.: Discussion of Plane Strain Crack Toughness Testing of High Strength Metallic Materials. ASTM STP410 (1966), pp. 77–79Search in Google Scholar

25 Paris, P. C.; Sih, G. C.: Stress Analysis of Cracks, ASTM STP381 (1964), pp. 30–8110.1520/STP26584SSearch in Google Scholar

26 Tada, H.; Paris, P. C.; Irwin, G. R.: The Stress Intensity Analysis of Cracks Handbook, 2th Edition, Paris Productions, (1985)Search in Google Scholar

27 Gallagher, J. P.: A Generalized Development of Yield Zone Models. AFFDL-TM-74-28-FBR, Wright Patterson Air Force Laboratory (1974)10.21236/ADA956516Search in Google Scholar

28 de Koning, A. U.; ten Hoeve, H. J.; Hendriksen, T. K.: The Description of Crack Growth on the Basis of the Strip-Yield Model for Computation of Crack Opening Loads, The Crack Tip Stretch and Strain Rates, NLR-TP-97511, (1997)Search in Google Scholar

29 Elber, W.: The Significance of Fatigue Crack Closure, ASTM STP486 (1971), pp. 230–24210.1520/STP26680SSearch in Google Scholar

30 Beghini, M.; Bertini, L.; Vitale, E.: Fatigue Crack Growth in Residual Stress Fields: Experimental Results and Modelling, Fatigue and Fracture of Engineering Materials and Structures17 (1994), No. 12, pp. 1433–144410.1111/j.1460-2695.1994.tb00786.xSearch in Google Scholar

Published Online: 2013-05-28
Published in Print: 2006-07-01

© 2006, Carl Hanser Verlag, München

Articles in the same Issue

  1. Inhalt/Contents
  2. Inhalt
  3. Vorwort/Editorial
  4. Vorwort
  5. Fachbeiträge/Technical Contributions
  6. Lokale Konzepte zur betriebsfesten Auslegung von Naht- und Punktschweißverbindungen*
  7. Optimierung der Schweißnahtlänge mit Hilfe der Lebensdauerberechnung*
  8. Lebensdauerbewertung hochfester Hybridschweißverbindungen unter Schwingbeanspruchung*
  9. Ein Kerbspannungskonzept für die schwingfeste Bemessung von Aluminium-Schweißnähten*
  10. Werkstoff- und Fertigungseinfluss auf die Schwingfestigkeit geschweißter Omnibusstrukturteile*
  11. Simulations of fatigue crack propagation in friction stir welds under flight loading conditions*
  12. Nietverbindungen für höchste Drehmomentbelastungen am Beispiel einer Nutzfahrzeug-Schaltkupplung*
  13. Werkstoffdatenbank mit Schwingfestigkeitsdaten für Berechnung und Konstruktion*
  14. Virtuelle Bewertung von Fügestellen im Karosseriebau*
  15. Schweißnaht oder Schweißpunkt? Das ist hier die Frage!*
  16. Vorschau/Preview
  17. Vorschau
https://doi.org/10.3139/120.100746

Articles in the same Issue

  1. Inhalt/Contents
  2. Inhalt
  3. Vorwort/Editorial
  4. Vorwort
  5. Fachbeiträge/Technical Contributions
  6. Lokale Konzepte zur betriebsfesten Auslegung von Naht- und Punktschweißverbindungen*
  7. Optimierung der Schweißnahtlänge mit Hilfe der Lebensdauerberechnung*
  8. Lebensdauerbewertung hochfester Hybridschweißverbindungen unter Schwingbeanspruchung*
  9. Ein Kerbspannungskonzept für die schwingfeste Bemessung von Aluminium-Schweißnähten*
  10. Werkstoff- und Fertigungseinfluss auf die Schwingfestigkeit geschweißter Omnibusstrukturteile*
  11. Simulations of fatigue crack propagation in friction stir welds under flight loading conditions*
  12. Nietverbindungen für höchste Drehmomentbelastungen am Beispiel einer Nutzfahrzeug-Schaltkupplung*
  13. Werkstoffdatenbank mit Schwingfestigkeitsdaten für Berechnung und Konstruktion*
  14. Virtuelle Bewertung von Fügestellen im Karosseriebau*
  15. Schweißnaht oder Schweißpunkt? Das ist hier die Frage!*
  16. Vorschau/Preview
  17. Vorschau
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