The Paton Welding Journal, 2018, №09



2018 №09 (02)

DOI of Article 10.15407/tpwj2018.09.03

2018 №09 (04)

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The Paton Welding Journal, 2018, #9, 13-17 pages
 

Characteristics of structural strength of D16T alloy welded joints, produced by friction stir welding

A.G. Poklyatsky¹, Yu.V. Golovatyuk², T.M. Labur¹, O.P. Ostash² and S.I. Motrunich¹

¹E.O. Paton Electric Welding Institute of the NAS of Ukraine 11 Kazimir Malevich Str., 03150, Kyiv, Ukraine. E-mail: office@paton.kiev.ua
²G.V. Karpenko Physico-Mechanical Institute of the NAS of Ukraine 5 Nauchnaya Str., 79060, Lviv, Ukraine

A series of research was performed to study the characteristics of structural strength of butt joints of aluminium alloy D16T 2 mm thick, produced by friction stir welding. Features of weld formation and degree of metal softening in the zone of the produced permanent joint were analyzed. Mechanical testing of welded joint samples was performed at static and cyclic loading. Diagrams of fatigue crack growth rates in the base metal, heat-affected zone and thermomechanical impact zone, on the boundary of these zones and in the weld metal were plotted. It is shown that the characteristics of cyclic crack resistance of weld metal of these joints are more than two times higher than the respective values for base metal that is indicative of the good prospects for application of friction stir welding in fabrication of critical structures from D16T alloy. 19 Ref., 8 Figures.
Keywords: aluminium alloy D16T, friction stir welding, microstructure, cyclic crack resistance, structural strength
 
Received:                26.10.18
Published:               25.10.18
 
 
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