The Paton Welding Journal, 2005, №02

2005 №02 (11)

2005 №02 (02)

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The Paton Welding Journal, 2005, #2, 2-10 pages

Effect of microstructural factors on sensitivity of welds with ultra-low carbon content to brittle fracture

G.M. Grigorenko, V.V. Golovko, V.A. Kostin, V.F. Grabin

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

Abstract
Morphological features of microstructure of weld metal with ultra-low carbon content have been studied. It is shown that in such welds both MAC-phase and lamellar forms of ferrite are the structural factors that cause instability of properties. It has been found that the content of the MAC-phase should not exceed 5-6 vol.% at a low content of ferrite with an ordered secondary phase to provide consistently high properties at low temperatures. It is shown that impact toughness of the welds studied rises with increase in the content of the ductile component in fracture.
Keywords: arc welding, low-alloy steels, weld metal, ultra-low content of carbon, structure, acicular ferrite, MAC-phase, ferrite with ordered and disordered secondary phase, structural components, quasi-cleavage, impact toughness

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Suggested Citation

G.M. Grigorenko, V.V. Golovko, V.A. Kostin, V.F. Grabin (2005) Effect of microstructural factors on sensitivity of welds with ultra-low carbon content to brittle fracture. The Paton Welding J., 02, 2-10.

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