Accession Number : ADA112185

Title :   Passive Films, Surface Structure and Stress Corrosion and Crevice Corrosion Susceptibility. Part I. A Qualitative Ellipsometric-Electrochemical Approach for the Study of Film Growth under Organic Coatings. Part II. Hydrogen Interactions with Stressed Titanium-Palladium Alloys and Stressed Vanadium Explored with Field Ion Microscopy.

Descriptive Note : Technical summary rept. no. 10,

Corporate Author : NATIONAL BUREAU OF STANDARDS WASHINGTON DC NATIONAL MEASUREMENT LAB

Personal Author(s) : Kruger,J ; Carroll,J J ; Melmed,A J ; Ritter,J J

PDF Url : ADA112185

Report Date : Aug 1980

Pagination or Media Count : 48

Abstract : The objective of the work was to gain a deeper understanding of the mechanisms governing the corrosion protective actions of paints on metal surfaces. Computer modeling and experiments with collodion coatings on iron substrates indicated that changes in the ellipsometric parameter delta could, for the most part, be safely interpreted as thickness alterations in the substrate oxide film. Experiments with the Fe-collodion system in dilute chloride solutions exhibited three sequential stages of activity, two of which could be interpreted in terms of corrosion mechanisms using the optical and electro-chemical measurements. Three titanium-palladium alloys, nominally containing one, two, and three at. % palladium, were prepared by vacuum annealing titanium wires that were previously electroplated with palladium thin films. Field ion micrographs obtained from these materials at temperatures less than 30 K indicated significant alloy inhomogeneities. In addition, the micrographs indicated that the alloys offered no greater resistance to hydrogen/stress induced crack formation and development than unalloyed titanium under similar conditions.

Descriptors :   *Electrochemistry, *Passive systems, *Coatings, *Measurement, *Thin films, Corrosion, Computer applications, Iron, Substrates, Surface chemistry, Surface properties, Paints, Vanadium, Ellipsometers, Cracks, Organic coatings, Hydrogen

Subject Categories : Physical Chemistry
      Coatings, Colorants and Finishes

Distribution Statement : APPROVED FOR PUBLIC RELEASE