The effect of nitrogen on the sensitization of AISI 304 stainless steel

Journal Article · Tue Oct 01 04:00:00 EDT 1985 · Corrosion (Houston); (United States)

DOI:https://doi.org/10.5006/1.3582983· OSTI ID:6303744

Mozhi, T A; Clark, A T; Johnson, W B; Macdonald, D D; Nishimoto, K

Thermodynamic calculations have been used to construct time temperature sensitization (TTS) diagrams for AISI 304 stainless steels (SS). The quantitative Stawstrom and Hillert model, which is based on chromium diffusion control of sensitization, was used to calculate the TTS diagrams. Electrochemical potentiokinetic reactivation (EPR) tests were performed on these steels, with various nitrogen additions, to obtain the experimental TTS curves. The calculated and experimental TTS diagrams have been compared to better understand nitrogen addition effects on the sensitization kinetics of AISI 304 SS. These results indicate that nitrogen additions below 0.16 wt% retard the sensitization kinetics; one possible mechanism by which this is achieved is an increase in chromium concentration adjacent to the grain boundaries, which decreases the chromium concentration gradient between the austenite matrix and the grain boundaries and hence retards carbide growth.

• Research Organization: Department of Metallurgical Engineering, Ohio State University, Columbus, OH
• OSTI ID: 6303744
• Journal Information: Corrosion (Houston); (United States), Journal Name: Corrosion (Houston); (United States) Vol. 41:10; ISSN CORRA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
ALLOYS
CALCULATION METHODS
CHEMISTRY
CHROMIUM
CHROMIUM ALLOYS
CHROMIUM STEELS
CHROMIUM-NICKEL STEELS
CORROSION RESISTANT ALLOYS
CRYSTAL STRUCTURE
DIFFUSION
ELECTROCHEMISTRY
ELEMENTS
GRAIN BOUNDARIES
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
IRON ALLOYS
IRON BASE ALLOYS
MATERIALS
MATERIALS TESTING
METALLURGICAL EFFECTS
METALS
MICROSTRUCTURE
NICKEL ALLOYS
NITROGEN
NITROGEN ADDITIONS
NONMETALS
PHYSICAL PROPERTIES
POTENTIOMETRY
SENSITIVITY
STAINLESS STEEL-304
STAINLESS STEELS
STEELS
TEMPERATURE EFFECTS
TESTING
THERMODYNAMIC PROPERTIES
TITRATION
TRANSITION ELEMENTS