Journal of the Serbian Chemical Society 2011 Volume 76, Issue 7, Pages: 1027-1035
https://doi.org/10.2298/JSC100726090R
Full text ( 996 KB)
Cited by
Corrosion of an austenite and ferrite stainless steel weld
Rajaković-Ognjanović Vladana N. (Faculty of Civil Engineering, Institute of Hydraulic and Environmental Engineering, Belgrade)
Grgur Branimir N. (Faculty of Technology and Metallurgy, Department of Physical Chemistry and Electrochemistry, Belgrade)
Dissimilar metal connections are prone to frequent failures. These failures
are attributed to the difference in the mechanical properties across the
weld, the coefficients of thermal expansion of the two types of steels and
the resulting creep at the interface. For the weld analyzed in this research,
it was shown that corrosion measurements can be used for a proper evaluation
of the quality of weld material and for the prediction of whether or not the
material, after the applied welding process, can be in service without
failures. It was found that the corrosion of the weld analyzed in this
research resulted from the simultaneous activity of different types of
corrosion. In this study, electrochemical techniques including polarization
and metallographic analysis were used to analyze the corrosion of a weld
material of ferrite and austenitic stainless steels. Based on surface,
chemical and electrochemical analyses, it was concluded that corrosion
occurrence was the result of the simultaneous activity of contact corrosion
(ferrite and austenitic material conjuction), stress corrosion (originating
from deformed ferrite structure) and inter-granular corrosion (due to
chromium carbide precipitation). The value of corrosion potential of -0.53 V
shows that this weld, after the thermal treatment, is not able to repassivate
a protective oxide film.
Keywords: welding, corrosion, stainless steel