Automatic Welding, 2016, №06



2016 №06 (13)

DOI of Article 10.15407/as2016.06.14

2016 №06 (15)

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Avtomaticheskaya Svarka (Automatic Welding), #6, 2016, pp. 88-92

Effect of structure and properties of aluminium-lithium alloy welded joints produced by argon-arc and friction stir welding methods

L.I. Markashova, A.G. Poklyatsky And O.S. Kushnaryova

E.O. Paton Electric Welding Institute, NASU 11 Kazimir Malevich Str., 03680, Kiev, Ukraine. E-mail: office@paton.kiev.ua


Abstract
An essential difference in formation of structural-phase state at application of different welding conditions — friction stir welding compared to argon-arc welding — is considered in the case of welded joints of complex aluminium-lithium alloys. The urgency of comprehensive experimental-analytical assessment of interrelation of welded joint structure and properties is also shown. Assessments of specific contribution of structural-phase state (chemical composition, phase dimensions, grain, subgrain and dislocation structure) into the change of the main service properties of welded joints made by argon-arc welding and friction stir welding are considered, as well as the influence of welded joint structural state on the nature of distribution, level of growing internal stresses and their relaxation mechanisms under specific welding conditions. 10 Ref., 5 Figures.

Keywords: aluminium alloy, FSW, TIG welding, weld metal, phase precipitates, structure, dislocations, strengthening, strength characteristics, crack resistance


Received:                05.04.16
Published:               19.07.16


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