| 2000 №05 (02) | 2000 №05 (04) |
The Paton Welding Journal, 2000, #5, 14-18 pages
Structure of the ferrite band formed in the joint zone of ferritic-pearlitic steels in vacuum pressure welding
L.I. Markashova, G.M. Grigorenko, G.K. Kharchenko, V.V. Arsenyuk, S.G. Grigorenko, I.L. Bogajchuk
E.O. Paton Electric Welding Institute of the NASU 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.Abstract
Results of examination of peculiarities of structure and conditions of a ferrite band formation in the zone of joining ferritic-pearlitic steels during vacuum pressure welding are presented. It is shown that two types of ferrite are formed in the zone of welding which are distinguished by several features. It is established that decarburization of metal layers adjacent to the surface to be welded and thermodynamic instability of a pearlitic cementite in the high inner stress fields are the conditions which promote the formation of ferrite bands.
Keywords: vacuum pressure welding, ferrite band, cementite platelets, dislocation density, self-cleaning of surfaces
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