Determination of Tafel constants in nonlinear polarization curves. Master's thesis

Technical Report · Tue Dec 01 04:00:00 EST 1987

OSTI ID:7172933

O'Loughlin, T E

The presence of nonlinear behavior in potentiodynamic polarization plots has resulted in difficulty in determining the Tafel constants from such plots. A FORTRAN-based program involving numerical-differentiation techniques was used to determine the existence of the Tafel regions. Various alloys polarized in synthetic seawater and a 3.5% NaCl solution were analyzed. Although severe concentration polarization often dominated the cathodic branches, the techniques employed did allow for the selection of regions that approached linear behavior. The effects of concentration polarization in hindering the determination of Tafel constants were exemplified by the uncovering of a cathodic branch containing a small region where only activation polarization dominated, followed by the onset and total domination of concentration polarization. A method of determining where the anodic and cathodic currents begin to dominate the potentiodynamic polarization curve is introduced.

• Research Organization: Naval Postgraduate School, Monterey, CA (USA)
• OSTI ID: 7172933
• Report Number(s): AD-A-192335/8/XAB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360105* -- Metals & Alloys-- Corrosion & Erosion
99 GENERAL AND MISCELLANEOUS
990220 -- Computers
Computerized Models
& Computer Programs-- (1987-1989)
ALLOYS
CHEMICAL REACTIONS
CORROSION
CORROSIVE EFFECTS
FORTRAN
HYDROGEN COMPOUNDS
NONLINEAR PROBLEMS
OXYGEN COMPOUNDS
POLARIZATION
PROGRAMMING LANGUAGES
SEAWATER
WATER