Automatic Welding, 2018, №09



2018 №09 (02)

DOI of Article 10.15407/as2018.09.03

2018 №09 (04)

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Avtomaticheskaya Svarka (Automatic Welding), #9, 2018, pp. 17-22

Characteristics of structural strength of d16t alloy welded joints,

A.G. Poklyatskii¹, Yu.V. Golovatuk², T.M. Labur¹, O.P. Ostash², S.I. Motrunich¹

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

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 cracks growth rate in the base metal, heat-affected and thermomechanical impact zones, 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 Fig.
Keywords: aluminium alloy D16T, friction stir welding, microstructure, cyclic crack resistance, structural strength

Received: 09.07.2018
Published: 20.09.2018

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