Chemistry - Structure - Property Interrelationships for Calcareous Deposits as Stand Alone Coatings (Second Year)
Abstract
Calcareous deposits which formed in natural sea water upon ASTMA710 steel polarized either potentiostatically, galvanostatically or by a mixed mode technique ( initially galvanostatic followed by potentiostatic) have been studied. Parameters investigated included variation of current density (potentiostatic control ) or potential (galvanostatic control ) with time, total charge transfer, deposit thickness, thickness-to-charge ratio, deposit morphology and deposit composition. A unique feature of cathodic protection in sea water is formation of calcareous deposits on metal surfaces. Advantageous aspects of these deposits, such as decrease in cathodic current requirement have been investigated by various author. In the present study specific attention has been focused upon the relative effect of type of polarization ( potentiostatic, galvanostatic or a mixed galvanostatic-potentiostatic mode) upon properties of the resultant calcareous deposits. Thus, for the potentiostatic polarization mode current density and, hence, hydroxide ion formation rate should decrease with time due to calcareous deposit development and resultant oxygen concentration polarization. For galvanostatic polarization, however, the hydroxide ion production rate remains constant with time.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 30, 1988
- Accession Number
- ADA202290
Entities
People
- J. S. Luo
- R. U. Lee
- Stanley W. Smith
- Timothy Y. Chen
- W. H. Hartt
Organizations
- Florida Atlantic University