Role of surface finishing on pitting corrosion of a duplex stainless steel in seawater

Journal Article · Mon Apr 01 04:00:00 EST 1996 · Journal of Materials Engineering and Performance

DOI:https://doi.org/10.1007/BF02650891· OSTI ID:230702

Salah-Rousset, N B; Chaouachi, M A ^[1]; Chellouf, A ^[2]

---

1. ENIT, Tunis (Tunisia). Lab. of Metallurgy and Materials
2. STEG, Tunis (Tunisia)

Localized corrosion of duplex UNS S32550 stainless steel in seawater was investigated in the laboratory and in field trials for several surface finish conditions: polished, ground, and sandblasted. Electrochemical data obtained by polarization curves showed that the smoother, polished surface had better characteristics (higher pitting and protection potentials) than the ground or sandblasted surfaces. However, despite its high degree of roughness, the sandblasted surface was the most resistant in field conditions, exhibiting the lowest number of sites attacked. Internal compressive stresses created by sandblasting seem also to have an unsensitizing effect on sensitized zones that exist in cast steel (due to repairs of mold defects), reducing its susceptibility to microbiologically influenced corrosion (MIC). Such stresses are not generated in polished or ground surfaces, and localized MIC attack can occur.

• Sponsoring Organization: USDOE
• OSTI ID: 230702
• Journal Information: Journal of Materials Engineering and Performance, Journal Name: Journal of Materials Engineering and Performance Journal Issue: 2 Vol. 5; ISSN 1059-9495; ISSN JMEPEG
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
42 ENGINEERING
BENCH-SCALE EXPERIMENTS
CHROMIUM ALLOYS
COPPER ALLOYS
ELECTROCHEMISTRY
FIELD TESTS
GRINDING
IRON BASE ALLOYS
MANGANESE ADDITIONS
MATERIALS
MOLYBDENUM ALLOYS
NICKEL ALLOYS
NITROGEN ADDITIONS
PITTING CORROSION
POLISHING
ROUGHNESS
SILICON ADDITIONS
SURFACE CLEANING
SURFACE PROPERTIES
THERMAL POWER PLANTS
WELDED JOINTS