FSW of lightweight aluminum structures: lap joint development

• Autorzy: Buffa G. , Fratini L.

Warianty tytułu

PL

Zastosowanie punktowego zgrzewania tarciowego z mieszaniem materiału zgrzeiny do łączenia lekkich struktur aluminium: opracowanie spojenia zakładkowego

• Języki publikacji: EN

Abstrakty

EN

In the last decade, the employ of Aluminum alloys in the automotive and aircraft industries appears to be the best technical solution as well as great challenge for the engineers; such materials present several advantages and a few shortcomings which have to be properly overcome. In particular, through a proper design to market, it is possible to improve at least three main aspects of the products requirements, namely active and passive safety increase, fuel costs reduction and environmental impact reduction. In turn, such materials present lower ductility with respect to steels, anisotropy phenomena and, what is more, they are often difficult to be welded or even non-weldable. For this last reason, in the last years, some alternative joining technologies have been proposed with the aim to take rid of the above reported shortcomings. Among these adhesive bonding, self-piercing mechanical fasteners, clinching and friction stir welding are probably the most interesting. All the cited techniques avoid the melting of the base material. In order to obtain a continuum joint the friction stir welding process (FSW) can be developed. Such process is a solid state welding technique in which a specially designed rotating pin is first inserted into the adjoining edges of the sheets to be welded with a proper nuting angle and then moved all along the joint. Such pin produces frictional and plastic deformation heating in the welding zone, and, as the tool moves, material is forced to flow around it in a quite complex flow pattern. In the paper, a wide experimental and numerical investigation on the lap joining of 2xxx aluminum alloys blanks by FSW is presented. In particular, self-piercing riveting, clinching and friction stir welding were taken into account. The influence of some relevant parameters is investigated with the aim to maximize the joint strength, just starting from the joint configuration. An accurate analysis on the obtained parts was carried out and the reached results gave important information on the investigated joining technique.

PL

Tematem niniejszej pracy są badania laboratoryjne oraz analiza numeryczna procesu spawania zakładkowego metodą Friction Stir Welding (FSW) stopów aluminium serii 2xxx. Analizie poddany został wpływ parametrów geometrycznych oraz technologicznych na wytrzymałość uzyskiwanych spoin. W pracy omówiono uzyskane wyniki oraz wynikające z nich wnioski.

Słowa kluczowe

EN

lap; FEM; tool geometry

• Wydawca: Wydawnictwa AGH
• Czasopismo: Computer Methods in Materials Science
• Rocznik: 2009
• Tom: Vol. 9, No. 1
• Strony: 123--129
• Opis fizyczny: Bibliogr. 14 poz., rys.

Twórcy

autor

Buffa G.

autor

Fratini L.

• Dipartimento di Tecnologia Meccanica, Produzione e Ingegneria Gestionale University of Palermo, Italy

Bibliografia

• 1.  Guerra,  M.,   Schmidt,   C.,  McClure,   L.C.,  Murr, L.E., Nunes, A.C. , Flow patterns during friction stir welding, Materials characterization, 49, 2003, 95-101.
• 2.  Liu, H.J., Fujii, H.M., Maeda, M., Nogi, K., Tensile properties and fracture locations of friction-stir-welded joints of 2017-T351  aluminum alloy, J. Mat. Proc. Techn., 142, 2003, 692-696.
• 3.  Lee, W.B., Yeon, Y.M., Jung, S.B., The improvement of mechanical properties of friction-stir-welded A356 Al alloy, Mat. Sci. Eng., A355, 2003, 154-159.
• 4.  Peel, M., Steuwer, A., Preuss, M., Withers, P.J., Microstructure, mechanical properties and residual stresses as a function of welding speed in aluminium AA5083 friction stir welds, Acta Materialia, 51(16), 2003, 4791-4801.
• 5.  Staron, P., Koçak, M., Williams, S., Wescott, A., Residual stress in friction stir-welded Al sheets, Physica B, 350(1-3), 2004, E491-E493.
• 6.  Dickerson, T.L., Prydatek, J., Fatigue of friction stir welds in alluminium alloys that contain roots flaws, Int. J. Fatigue, 25, 2003, 1399-1409.
• 7.  Sutton, M., Reynolds, A., Yang, B., Taylor, R., Mixed mode I/II fracture of 2024-T3 friction stir welds, Engineering Fracture Mechanics, 70, 2003, 2215-2234.
• 8.  Bussu, G., Irving, P.E., The role of residual stress and heat affected zone properties on fatigue crack propagation in friction stir welded 2024-T351 aluminum joints, Int. J. Fatigue, 25(1), 2003, 77-88.
• 9.  John, R., Jata, K.V., Sadananda, K., Residual stress effects on near-threshold fatigue crack growth in friction stir welds in aerospace alloys, Int. J. Fatigue, 25 (9-11), 2003,   939-948.
• 10. Song, M., Kovacevic, R., Thermal modeling of friction stir welding in a moving coordinate system and its validation, Int. J. of Machinę Tools & Mań., 43, 2003, 605-615.
• 11. Xu, S., Deng, X., A three-dimensional model for the friction-stir welding process, Proceedings of the 21th South-eastern Conference on Theoretical and Applied Mechanics, 2002.
• 12. Fratini, L., Buffa, G., CDRX modelling in friction stir welding of aluminum alloys, Int. J. of Machine Tools & Manufacture, 45/10, 2005, 1188-1194.
• 13. Buffa, G., Hua, J., Shivpuri, R., Fratini, L., A continuum based FEM model for friction stir welding - model development, Mat. Sci. Eng. A, 419/1-2, 2006, 381-388.
• 14. Buffa, G., Hua, J., Shivpuri, R., Fratini L., Design of the friction stir welding tool using the continuum based FEM model, Mat. Sci. Eng. A, 419/1-2, 2006, 389-396.