Avtomaticheskaya Svarka (Automatic Welding), #4, 2017, pp. 21-24
Physico-mechanical properties of thin-sheet aluminum alloy D16 butt joints produced by friction stir welding
A.G. Poklyatsky, S.I. Motrunich and I.N. Klochkov
E.O. Paton Electric Welding Institute, NASU
11 Kazimir Malevich Str., 03680, Kiev, Ukraine. E-mail: office@paton.kiev.ua
Abstract
A complex of investigations was carried out to study the strength characteristics of welded butt joints of structural aluminum alloy D16 of 2 mm thickness, produced by friction stir welding. It was shown that the use of friction stir welding provides the formation of a permanent joint with a minimum level of stress concentration in the transition zones from the weld to the base material and allows avoiding the formation of defects in the welds such as pores, macroinclusions of oxide film and hot cracks caused by melting and crystallization of metal in fusion welding. As a result of intensive plastic deformation in the weld metal, a homogeneous disoriented structure with a grain size of 3–4 ?m and with dispersed phase precipitations of not more than 1 ?m is formed, and in the regions adjacent to it the elongation and distortion of grains in the direction of movement of the plasticized metal occurs in the zone of thermomechanical action. Due to this, the hardness of metal in the joint zone, the tensile strength under uniaxial tension and the fatigue strength under cyclic loads are increased. 11 Ref., 6 Figures.
Keywords: friction stir welding, aluminum alloy D16, hardness, tensile strength, fatigue resistance
Received: 20.02.17
Published: 17.04.17
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