Characteristics of High Frequency Peening Methods and their Effects on the Fatigue Strength of Welded Details

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Research has been initiated on the effects of high frequency peening methods on the fatigue strength. These methods combine an improvement of weld toe profile with an initiation of compressive residual stresses and surface hardening. The effects of two techniques, High Frequency Impact Treatment (HiFIT) and Ultrasonic Impact Treatemnt (UIT) are compared. Laser measurements of the weld seam prove that both methods increase the overall weld toe radii. Further, residual stress measurements verify the introduction of compressive residual stresses at least up to a depth of 1 mm. The values meet the yield strength combined with an increase of the surface hardness. These material mechanical effects cause an increased crack resistance. Crack detection methods prove that the material mechanical effects yield to a retarded crack initiation. Experimental results show that these effects lead to a significant increase of the fatigue strength and reduced slopes of the SN-curves.

Info:

Periodical:

Key Engineering Materials (Volumes 348-349)

Edited by:

J. Alfaiate, M.H. Aliabadi, M. Guagliano and L. Susmel

Pages:

429-432

Citation:

I. Weich and T. Ummenhofer, "Characteristics of High Frequency Peening Methods and their Effects on the Fatigue Strength of Welded Details ", Key Engineering Materials, Vols. 348-349, pp. 429-432, 2007

Online since:

September 2007

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$38.00

[1] Ummenhofer, T, Weich, I and Nitschke-Pagel, T.: IIW Document XIII-2085-0 (2005).

[2] Ummenhofer, T., Weich, I. C., Nitschke-Pagel, T. N., Proceedings of the 16th International Offshore and Polar Engineering Conference, Vol. IV, pp.98-105, San Francisco, California, USA (2006).

[3] Dürr, A.: Zur Ermüdungsfestigkeit von Schweißkonstruktionen aus höherfesten Baustählen bei Anwendung von Nachbehandlungsverfahren, Fakultät Bau- und Umweltingenieurwissenschaften, University Stuttgart, Stuttgart, Germany (2006).

DOI: https://doi.org/10.1002/stab.200590066

[4] Lihavainen, V. -M.: A novel approach for assessing the fatigue strength of ultrasonic impact treated welded structures, Lappeenranta University Technology, Lappeenranta Finland (2006).

[10] [4] [10] [5] [10] [6] [10] [7] [10] 100 1000 load cycles [ ] stress range [MPa] as welded, 95%−Fractile UIT−treated, 95%−Fractile EC HiFIT.

[56] 82 161.

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