The Paton Welding Journal, 2021, №05



2021 №05 (10)

DOI of Article 10.37434/tpwj2021.05.11

2021 №05 (01)

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The Paton Welding Journal, 2021, #5, 65-68 pages

Application of fractal and metallographic analyses for evaluation of quality of weld metal

O.O. Shtofel², V.V. Holovko¹ and T.G. Chyzhska²

¹E.O. Paton Electric Welding Institute of the NAS of Ukraine 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine. E-mail: office@paton.kiev.ua
²National Technical University of Ukraine «Igor Sikorsky Kyiv Polytechnic Institute» 37 Peremohy Prosp., 03056, Kyiv, Ukraine

Abstract
When analyzing the factors that determine the mechanical properties of welds, it is necessary to take into account both the size of individual components of the structure and their morphology. It is shown that the use of the method of fractal analysis makes it possible to numerically determine such parameters of weld metal microstructure, as the size of nonmetallic inclusions, and branching of grain boundaries, which was impossible at analysis of metallographic images. The results are obtained, which indicate the need to include in the multifractal analysis the characteristics that describe the morphological features of microstructural components, the distribution of nonmetallic inclusions by size, and the level of alloying of the solid solution. Research directions for the development of multifractal analysis of welded joints have been identified. 10 Ref., 2 Tables, 6 Figures.
Keywords: metal of welded joints, fractal and metallographic analyses, structural parameters, mechanical characteristics

Received 30.03.2021

References

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