Accession Number : ADA192482

Title :   Significance of the Local Electrode Potential within Pits, Crevices and Cracks.

Descriptive Note : Technical rept.,

Corporate Author : PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MATERIALS SCIENCE AND ENGINEE RING

Personal Author(s) : Pickering, Howard W

PDF Url : ADA192482

Report Date : Feb 1988

Pagination or Media Count : 36

Abstract : This paper begins with a review of the experimental measurements of the electrode potential within pits, crevices and cracks for several commercially important alloy systems. Then, recent results for crevicing are reviewed. They give further insight into the relationship of the important parameters within the cavity: IR drop, Flade or passivation potential and solution composition, namely that stable crevice corrosion occurs when the electrode potential in the crevice is less oxidizing than the Flade potential of the crevice solution. This result fully supports and contributes to a more detailed understanding of the potential shift mechanism, as originally outlined for pitting in iron, and more recently applied widely to pitting, crevicing, stress corrosion and corrosion fatigue in different alloy systems.

Descriptors :   *CRACKS, *IRON, *PITTING, *ELECTRICAL RESISTANCE, ALLOYS, COMPOSITION(PROPERTY), CORROSION, ELECTRODES, EXPERIMENTAL DATA, FATIGUE(MECHANICS), MEASUREMENT, PASSIVITY, SHIFTING, SOLUTIONS(GENERAL), SOLUTIONS(MIXTURES), STABILITY, STRESS CORROSION

Subject Categories : Physical Chemistry
      Electricity and Magnetism

Distribution Statement : APPROVED FOR PUBLIC RELEASE