Residual stress reduction by beam defocusing in beam welding processes
- Residual stresses arising during welding, especially in high energy beam welding, can reach levels up to the material specific yield strength causing service life mitigating consequences through stress relaxation or stress corrosion cracking. A number of processes were developed like stress relief annealing or the low-stress-no-distortion-technique to reduce these stresses. But such methods are only applicable for wider welds and simple component geometries or they are cost-intensive. The method presented in this paper uses the welding beam after welding in a defocused mode for heating the material regions in a certain distance from the weld on both sides. With this process it is possible to decrease the stresses in small welds with high stress gradients without any contact surfaces or additional equipment. Dependent on the component geometry and on the laser power it is possible to use different parameters for this process. The adjustable process parameters are the radius and theResidual stresses arising during welding, especially in high energy beam welding, can reach levels up to the material specific yield strength causing service life mitigating consequences through stress relaxation or stress corrosion cracking. A number of processes were developed like stress relief annealing or the low-stress-no-distortion-technique to reduce these stresses. But such methods are only applicable for wider welds and simple component geometries or they are cost-intensive. The method presented in this paper uses the welding beam after welding in a defocused mode for heating the material regions in a certain distance from the weld on both sides. With this process it is possible to decrease the stresses in small welds with high stress gradients without any contact surfaces or additional equipment. Dependent on the component geometry and on the laser power it is possible to use different parameters for this process. The adjustable process parameters are the radius and the power of the defocused beam and the transversal and longitudinal distances between the welding and the defocused beam. In this work the mechanism and the influence of the process parameters are investigated by FEM-simulation and a number of experiments on the ferritic steel S355J2+N with 5 mm thickness. The best experimental result presented in this paper shows a stress reduction of about 73 %.…
Autor*innen: | Florian Tölle, Andrey GumenyukORCiD, Michael RethmeierORCiD |
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Persönliche Herausgeber*innen: | E. Halmoy |
Dokumenttyp: | Beitrag zu einem Tagungsband |
Veröffentlichungsform: | Verlagsliteratur |
Sprache: | Englisch |
Titel des übergeordneten Werkes (Englisch): | 13th NOLAMP conference - 13th Conference on laser materials processing in the nordic countries (Proceedings) |
Jahr der Erstveröffentlichung: | 2011 |
Herausgeber (Institution): | Norwegian university of science and technology |
Erste Seite: | 235 |
Letzte Seite: | 245 |
Freie Schlagwörter: | High energy beam welding; Laser scanner optics; Post-weld heat treatment; Residual stresses; Stress reduction |
Veranstaltung: | 13th NOLAMP conference - 13th Conference on laser materials processing in the nordic countries |
Veranstaltungsort: | Trondheim, Norway |
Beginndatum der Veranstaltung: | 27.06.2011 |
Enddatum der Veranstaltung: | 29.06.2011 |
ISBN: | 978-82-998664-1-5 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 19.02.2016 |
Referierte Publikation: | Nein |