Assessing Susceptibility to Chromium Carbide Precipitation in Cr-Mn Austenitic Stainless Steel Welds
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Date
2017
Authors
Amuda, M.O.H.
Enumah, K.S.
Onitiri, M.A.
Osoba, L.O.
Journal Title
Journal ISSN
Volume Title
Publisher
Unilag Journal of Medicine, Science and Technology (UJMST)
Abstract
Chromium-manganese austenitic stainless steel is a low cost grade with metallurgical
and mechanical properties approximating a standard nickel-chromium austenitic
stainless steel. It serves as a good substitute to the standard nickel-chromium grade
owing to the high cost of nickel. But, there is little information on its weldability
particularly the influence of welding parameters on chromium carbide precipitation in
the heat affected zone. This limits its structural application through fusion welding.
Therefore, in this paper, carbide precipitation in chromium-manganese austenitic
stainless steel welds was investigated in the heat input range 180 - 300 J/mm under
different combinations of arc current and welding speeds. Microstructural analysis after
10% oxalic acid electrolytic etch revealed that increasing heat input produced significant
changes in microstructure of the welds with wider sensitized structure at heat input
greater than 206 J/mm. Microstructure of welds produced at heat input lower than 206
J/mm was free of chromium carbide precipitation. This level of heat input which
corresponds to arc current of 110 -125A and welding speeds in the range 319- 395
mm/min show that sensitized region associated with chromium carbide precipitation can
be safely avoided during fusion welding of this grade of austenitic stainless steel through
carefully selected welding parameters.
Description
Keywords
Austenitic Stainless Steel Weld, Chromium Carbide Precipitation, Heat Affected Zone, Microstructure, Welding Parameters
Citation
Amuda, M.O.H. Enumah, K.S. Onitiri, M.A. Osoba, L.O. (2017). Assessing Susceptibility to Chromium Carbide Precipitation in Cr-Mn Austenitic Stainless Steel Welds. Unilag Journal of Medicine, Science and Technology (UJMST); 5(2) 109-122