Naslov
Fatigue crack growth in friction stir welded AA 2024 T joint

Autori
Sedmak, Aleksandar ; Kozak, Dražan

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, pp prezentacija, znanstveni

Izvornik
Knjiga apstrakta Mini-Symposium Stochastic Vibrations and Fatigue: Theory and Applications / (Stevanović) Hedrih, Katica ; Mitrović, Radivoje ; Zhao, Junfeng ; Trišović, Nataša ; Atanasovska, Ivana - Beograd : SANU, MI, 2017

Skup
Mini-Symposium Stochastic Vibrations and Fatigue: Theory and Applications

Mjesto i datum
Beograd, Srbija, 04.07.2017

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Extended finite element method, fatigue crack growth, friction stir welding, T joint, AA 2024 T351

Sažetak
The large scale use of welding for joining of aerospace structures has long being inhibited by the difficulty of production of Al alloys welds with high fatigue strength, especially in the case of 2XXX and 7XXX series. These types of aluminum alloys are usually perceived as non-weldable due to limited porosity and microstructure during solidification in the fusion zone. There is also a substantial loss in the mechanical properties as related to the base material. The Welding Institute (TWI) came up with Friction Stir Welding (FSW) in 1991 as a process for joining Al alloys in the solid state, providing good mechanical properties and avoiding aforementioned problems, [1]. The concept behind FSW can be perceived as very simple, but still a bit complex when applied to produce T joints, [2-4]. Another problem is lack of data regarding structural integrity of such weldments, especially when dynamic loading is applied, i.e. when welded component life is limited by fatigue crack growth. The Extended Finite Element Method (xFEM) has been applied to simulate fatigue crack growth in an AA2024-T351 T welded joint, 5 mm thick, made by friction stir welding. The ABAQUS and Morfeo software has been used. Tensile fatigue loading (mean stress 10 MPa, stress ratio R=0) is applied to T joints with a configuration suitable for reinforced panels where both skin and the web (reinforcement or stiffener) is made of a high strength AA2024-T351. Crack is introduced in one edge of the skin base material. The properties of materials and geometry of T joint are adopted from available experiments. Following numerical results are obtained: crack front coordinates (x, y, z) and stress intensity factors (KI, KII, KIII and Kef) distribution along the crack tip, as well as the fatigue life estimation for every crack propagation step. The main objective of this research is to better understand fatigue behaviour of friction stir welded T joint of AA2024-T351.

Izvorni jezik
Engleski

Znanstvena područja
Strojarstvo

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