| 2021 №09 (02) |
DOI of Article 10.37434/as2021.09.03 |
2021 №09 (04) |
Avtomaticheskaya Svarka (Automatic Welding), #9, 2021, pp. 19-23
Some advantages of welded joints of aluminum 1201 alloy produced by friction stir welding
A.G. Poklyatsky, S.I. Motrunich, I.M. Klochkov, T.M. Labur
E.O. Paton Electric Welding Institute. 11 Kazymyr Malevych Str., 03150 Kyiv, Ukraine. E-mail: office@paton.kiev.ua
The article analyzes the structural features, characteristics of strength and resistance to initiation and propagation of operational cracks of butt joints of aluminum 1201 alloy of 2 mm thickness, produced by friction stir welding (FSW) and argon arc welding with non-consumable electrode (AAWNCE). It is shown that in FSW as a result of intensive plastic deformation of the metal in the weld nugget, a fine-grained structure with a grain size of 5…6 μm is formed. In the zone of thermomechanical influence, deformed long grains are observed, oriented in the direction of movement of the plasticized metal, and small equiaxial grains, the size of which varies within 4…12 μm. Whereas in AAWNCE of this alloy the weld metal has a characteristic cast structure with large (0.20…0.25 mm) dendrites. The absence of penetrations and reinforcements in the welds produced by FSW, allows avoiding high levels of stress concentration at the places of transition from the weld to the base material, which negatively affect the service and life characteristics of welded joints. The peculiarities of the formation of permanent joints in the solid phase during FSW also help to reduce the degree of softening of the metal in the welding zone and increase their tensile strength, resistance to initiation and propagation of operational cracks. 15 Ref., 7 Fig.
Keywords: microstructure, hardness, tensile strength, resistance to initiation and propagation of operational cracks
Received: 08.07.2021
References
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