2009 №01 (12) 2009 №01 (02)

TPWJ, 2009, #1, 2-5 pages


Journal                    The Paton Welding Journal
Publisher                 International Association «Welding»
ISSN                       0957-798X (print)
Issue                       № 1, 2009 (January)
Pages                       2-5
E.O. Paton Electric Welding Institute, NASU, Kiev, Ukraine
The mechanisms of cracking of welded joints in tempering used to relieve stresses are considered. It has been found that welded joints on steel 10Kh9MFB with a homogeneous martensitic structure are insensitive to temper cracking. Formation of δ-ferrite in the martensitic structure may lead to cracking of the weld metal. Cracks form in tempering in the range of about 450-550 °C as a result of concentrated deformation within the zone of soft ferrite interlayers in development of secondary hardening of the martensitic matrix. A probable cause of hardening is precipitation of chromium carbide M7C3.
Keywords: arc welding, martensitic steel, welded joints, heat treatment, dispersion hardening, soft interlayers, temper cracking
Received:                17.09.08
Published:                28.01.09
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