| 2004 №04 (12) | 2004 №04 (02) |
The Paton Welding Journal, 2004, #4, 2-7 pages
Effect of chemical inhomogeneity on the formation of acicular ferrite in high-strength weld metal
G.M. Grigorenko, V.A. Kostin, V.V. Golovko, V.F. Grabin
E.O. Paton Electric Welding Institute of the NASU 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.Abstract
It is shown that the role of non-metallic inclusions in the formation of acicular ferrite is associated with the formation around non-metallic inclusions of regions of a solid solution with an increased content of nickel and manganese and different dislocation structure. Chemical composition of weld metal and different degree of a chemical inhomogeneity in the distribution of austenite-forming elements depend on the change in oxygen potential of the flux and adding of elements of deoxidizers (Al, Ti and Al + Ti) into it.
Keywords: arc welding, low-alloy, steels, weld, microstructure, acicular ferrite, chemical inhomogeneity, MAC-phase, non-metallic inclusions
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