Stainless Steels and Alloys: Why They Resist Corrosion
and How They Fail*
Other Forms of Corrosion
Other forms of corrosion observed for stainless steels
under service conditions include hydrogen-induced cracking, microbiologically
influenced corrosion, galvanic corrosion and knifeline attack. The nature
of environment including the operating conditions and the specific grade
of alloy will ultimately influence the form and degree of attack.
Concluding Remarks
The corrosion resistance of stainless steels depends
on the stability of an ultra thin passive film on their surfaces, which
is in turned determined by the alloy composition and the nature of the
environment. A good design should give due consideration to the nature
of the environment under which a stainless steel component operates. Breakdown
of passivity often leads to the localized corrosion such as pitting or
crevice corrosion. Welding or hot-working of stainless steel may introduce
sensitized structure and subsequently lead to weld decay or intergranular
stress corrosion cracking. Chloride, hydrogen and hydrogen sulfide are
common species that induce cracking of stainless steels. Proper tests should
be performed to evaluate the suitability of a specific grade of stainless
steel for a specific application. A number ASTM standards and NACE recommended
practices exist for this purposes [10].
If you want to know more about this
topic presented here, there is a short course entitled
"Stainless Steels and Alloys: Why They Resist
Corrosion and How They Fail". It can be
taken as in-house training course, online course or distance learning
course. References:
-
William D. Callister, Materials Science and Engineering,
4th edition, John Wiley & Sons, Inc., p428 1996.
-
C. J. Abbott, Concrete, May 1997, p28
-
A. J. Sedriks, Corrosion of Stainless Steels, John Wiley
& Sons, Inc., 2nd Edition, 1996, p17
-
J. E. Castle and J. H. Qiu, Corrosion Science, Vol.30, No.4,
p429-438, 1990.
-
J. H. Qiu, to be published.
-
J. H. Qiu, British Corrosion Journal, Vol. 33, No.4, pp 318-320,
1998.
-
K. S. Seow, T. Y. Song and J. H. Qiu, Anti-Corrosion Methods
and Materials, Vol.48, No.1, pp31-36, 2001
-
M. P. Seah, J. H. Qiu, P. J. Cumpson and J. E. Castle, NPL
Report, DMM(A)95, 1993
-
M. P. Seah, J. H. Qiu and J. E. Castle, Metrologia,
U.S.A., Vol.31 pp93-108, 1994
-
Annual Book of ASTM Standards, Vol.03.02, ASTM 100 Barr Harbour
Drive, PA 19428
-
NACE International Standards, NACE International, Houston,
TX 77216-1009
-
H. P. Leckie and H. H. Uhlig, J. Electrochem. Soc., Vol.113,
p1262, 1966
-
J-H. Wang, C. C. Su and Z. Szklarska-Smialowska, Corrosion,
Vol.44, p732, 1988
-
H. H. Uhlig and J. Gilman, Zeitschrift fuer Physikalische
Chemie, Vol.226, p127, 1964
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