The Paton Welding Journal, 2004, №07

2004 №07 (03)

2004 №07 (05)

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The Paton Welding Journal, 2004, #7, 15-20 pages

Morphological peculiarities of microstructure of weld metal from low-alloy steels with ultralow content of carbon

V.F. Grabin, V.V. Golovko, V.A. Kostin, I.I. Alekseenko

E.O. Paton Electric Welding Institute of the NASU 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.

Abstract
It is shown that in addition to the ordinary structures characteristic of welds hardened due to presence of pearlitic structures, welds with an ultralow carbon content also develop various ferrite morphologies, including an unusual form of laminar Widmanstatten ferrite, as well as massive forms of ferrite which solidify in the form of dendrite or as a «conglomerate» of round-shaped crystallites, separated from each other by boundary precipitations of MAC-phase, forming at the final stages of residual austenite decomposition. It is noted that to decrease the carbon liquation into weld metal its silicon content should not be higher than 0.3 wt.%.
Keywords: low-alloy steels, weld metal, evolution of fer¬rite, polygonal ferrite, acicular ferrite, Widmanstatten ferrite, massive ferrite, MAC-phase, structural constituents

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Suggested Citation

V.F. Grabin, V.V. Golovko, V.A. Kostin, I.I. Alekseenko (2004) Morphological peculiarities of microstructure of weld metal from low-alloy steels with ultralow content of carbon. The Paton Welding J., 07, 15-20.

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