Formation of highly corrosion resistant stainless steel surface alloys for marine environments by laser surface alloying

Conference · Thu Dec 31 04:00:00 EST 1998

OSTI ID:351818

Sridhar, K; Deshmukh, M B ^[1]; Khanna, A S ^[2]; Wissenbach, K ^[3]

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1. Naval Materials Research Lab., Bombay (India)
2. Indian Inst. of Tech., Bombay (India)
3. Fraunhofer Institut fuer Laser Technik, Aachen (Germany)

Austenitic stainless steels (SS) such as UNS S30403 are being used for numerous industrial applications due to their goad mechanical properties and weldability. However in aggressive marine environments such as seawater, they suffer from localized corrosion. Even though newly developed highly alloyed SS`s possess very high pitting resistance, they are susceptible to the formation of secondary phases. In the present study, a laser surface alloying technique was employed for the formation of highly alloyed austenitic stainless steel surfaces on conventional 304 SS substrate. Microstructural characterization by optical and SEM revealed finer cells of austenitic phase in the laser alloyed zones with molybdenum contents in the range of 3 to 15 wt%. The pitting corrosion resistance of the surface alloys were ascertained by immersion and potentiodynamic polarization tests and the repassivation behavior by cyclic polarization tests. Also the influence of microstructural features on pitting behavior of highly alloyed and laser surface alloyed steels is studied.

• OSTI ID: 351818
• Report Number(s): CONF-980316--
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
42 ENGINEERING
AUSTENITIC STEELS
CORROSION RESISTANCE
MICROSTRUCTURE
PITTING CORROSION
SEAWATER
STAINLESS STEEL-304
SURFACE COATING