| 2001 №10 (08) | 2001 №10 (10) |
The Paton Welding Journal, 2001, #10, 32-38 pages
Chemical microheterogeneity at the grain boundaries of HAZ metal of martensitic-bainitic steel 14KhGN2MDAFB
L.I. Mikhoduj, O.D. Smiyan, M.B. Movchan, V.D. Poznyakov, S.O. Antonov
E.O. Paton Electric Welding Institute of the NASU 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.Abstract
The process of a delayed fracture of HAZ in implant samples made from steel 14KhGN2MDAFB at the pre-fracture stage was examined using the method of electron Auger-spectrometry. It was established that during the delayed fracture of the welded joints the HAZ metal is subjected to redistribution of alloying and impurity elements inside the grains, enrichment of their boundaries by a number of embrittling impurity atoms that is an additional (except hydrogen) factor, predetermining the metal fracture at this type of tests.
Keywords: high strength steel, welded joint, heat-affected zone, Auger-spectrometry, tensile stresses, segregation of alloying and impurity elements, inhomogeneity, delayed fracture
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