Investigation of pitting corrosion of austenitic stainless steel types AISI 304L and AISI 317L, especially from the aspect of molybdenum content
DOI:
https://doi.org/10.62638/ZasMat1400Abstract
Austenitic stainless steels are among the most widely used types of stainless steel. The most commonly used grades are the American Iron and Steel Institute (AISI) 300 series of alloys. Starting from the basic 304 alloy (Fe-19Cr-10Ni), molybdenum is added to improve resistance to pitting (2-3 wt.% in the case of type 316 and 3-4 wt.% in type 317). Sensitisation due to chrome depletion during welding and other heat treatments, and the possible resultant intergranular corrosion, can be avoided through the use of low-carbon grades (304L, 316L, 317L, in which carbon is limited to 0.03 wt.% max.) or by adding titanium (type 321) or niobium and tantalum (type 347) to precipitate carbon at higher temperatures. The addition of chrome also imparts greater oxidation resistance, whilst nickel improves the ductility and workability of the material at room temperature. In this paper, pitting corrosion of austenitic stainless steels, specifically low-carbon types 317L and 304L, was investigated. The research results are presented in the form of cyclic potentiodynamic polarization curves. The results prove that the intensity of pitting corrosion of the tested austenitic stainless steels decreases by lowering the temperature of the 1.5% NaCl solution and the presence of molybdenum in the composition of steel type 317L.
Keywords:
austenitic stainless steels, molybdenum, pitting corrosion, temperature, chemical composition, cyclic polarization curvesReferences
F. King (2009) Corrosion Resistance of Austenitic and Duplex Stainless Steels in Environments Related to UK Geological Disposal, A Report to NDA RWM, Quintessa Limited, QRS-1384CR1,Version 1.2, UK.
E. Kikuti, R. Conrrado, N. Bocchi, S.R. Biaggio Rocha, R.C. Filho (2004) Chemical and Electrochemical Coloration of Stainless Steel and Pitting Corrosion Resistance Studies, J. Braz. Chem. Soc., 15(4), 472-480. https://doi.org/10.1590/S0103-50532004000400005
F.Bikić, D. Mujagić (2014) Investigation of possibility for reducing AISI 303 stainless steel pitting corrosion by microalloying with boron or zirconium, Bulletin of the Chemists and Technologists of Bosnia and Herzegovina, 42, 41 -46.
ASM International (1992) Handbook Volume 13, Corrosion, ASM International Committee, USA.
E. Hamada, K. Yamada, M. Nagoshi, N. Makiishi, K. Sato, T. Ishii, K. Fukuda, S. Ishikawa, T. Ujiro (2010) Direct imaging of native passive film on Stainless steel by aberration corrected STEM, Corros. Sci., 52, 3851– 3854. https://doi.org/10.1016/j.corsci.2010.08.025
C. Q. Jessen (2011) Stainless Steel and Corrosion, Damstahl a/s, Denmark.
ASTM G5 (1994) Standard Reference Test Method for Making Potentiostatic and Potenciodynamic Anodic Polarization Measurements.
R.T. Loto(2013) Pitting corrosion evaluation of austenitic stainless steel type 304 in acid chloride media, J. Mater. Environ. Sci., 4 (4), 448-459.
Z.Wang, Z. Feng, L. Zhang (2020) Effect of high temperature on the corrosion behavior and passive film composition of 316L stainless steel in high H2S-containing environments, Corrosion Science, 174, 08844. https://doi.org/10.1016/j.corsci.2020.108844
C. Escrivà-Cerdán, E. Blasco-Tamarit, D.M. García-García, J. García-Antón, A. Guenbour (2012) Passivation behaviour of Alloy 31 (UNSN08031) in polluted phosphoric acid at different temperatures, Corros. Sci.,56 ,114–122. https://doi.org/10.1016/j.corsci.2011.11.014
H.Iken, R. Basseguy, A. Guenbour, A.B. Bachir (2007) Classic and local analysis of corrosionbehaviour of graphite and stainless steels in polluted phosphoric acid, Electrochim.Acta, 52, 2580–2587. https://doi.org/10.1016/j.electacta.2006.09.013
A. Szewczyk-Nykiel, (2015) The influence of molibdenum on corrosion resistance of sintered austenitic stainless steels, Tehnical Transactions Mechanics, 4-M (26), 131–142.
