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2018 №02 (01) DOI of Article
10.15407/as2018.02.02
2018 №02 (03)


wAvtomaticheskaya Svarka (Automatic Welding), #2, 2018, pp. 11-18
 

Effect of metal structure on service properties of high-strength steel welded joints produced using different methods of welding

L.I. Markashova, V.D. Poznyakov, V.D. Shelyagin, E.N. Berdnikova, A.V. Bernatsky and T.A. Alekseenko


E.O. Paton Electric Welding Institute of the NAS of Ukraine 11 Kazimir Malevich Str., 03150, Kyiv, Ukraine. E-mail: office@paton.kiev.ua
 
Abstract
Evaluations of effect of forming structures and phase constituents on change of the most significant mechanical properties of welded joints were carried out based on investigation of peculiarities of formation of structural parameters in welded joints of high-strength steel, produced by different methods of fusion welding (laser, arc and hybrid laser-arc). A role of structural factors (alloying, phase constituents, grain, subgrain structure, distribution and density of dislocations, phase precipitations, their size and nature of distribution) was shown in providing the optimum properties of the welded joints and their service reliability. It is shown that the most significant structural-phase parameters and factors, providing under operation conditions, the necessary complex of properties of welded joints, namely strength (sy), fracture toughness (K1C) and crack resistance (tin), are fineness of grain and subgrain structures; dispersion of phase precipitations at their uniform distribution; absence of extended dislocation accumulations — potential concentrators of internal stresses (zone of nucleation and propagation of cracks). 23 Ref., 6 Figures.
Keywords: laser welding, arc welding, hybrid laser-arc welding, high-strength steel, welded joints, structure, phase composition, mechanical properties, fracture toughness, crack resistance
 
Received:                04.12.17
Published:               15.03.18
 
 
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