Menu
Search
Filters
Close
Menu

99506 PROTECTING ALUMINUM IN ATMOSPHERE THROUGH GALVANIC COUPLING TO ZINC

Picture for 99506 PROTECTING ALUMINUM IN ATMOSPHERE
Available for download
Product Number: 51300-99506-SG
ISBN: 99506 1999 CP
Author: R Diwan, A. Raman and X. Huang
Industry: Chemical Inhibitors
$0.00
$20.00
$20.00
Electrochemical polarization data for the individual thin film electrodes Al and Zn as well as in galvanic couple connecting the two together have been generated using atmospheric corrosion sensors developed recently. Thin films of these metals were subjected to cyclic fog testing and to continuous immersion in selected electrolytes corresponding to atmospheric condensates and were tested also in actual atmospheric exposure under bold (totally open and subject to direct hit by rain and sun light) and sheltered (not hit by rain and sun light) conditions. Results generally indicate that zinc corrodes by very large amount tending to protect aluminum in the process. Aluminum corrodes by the least and remains passivated under test conditions involving only plain water. In the presence of chloride ion, pitting is activated, though zinc provides initial protection and tends to stabilize passivation. Under open bold conditions, zinc electrode experiences the largest corrosion current densities and passivates itself and Al remains also in the passive state. The potentials of both electrodes converge to nearly the same value around +100 mV measured against an open silver film. Under the sheltered locations, both the corrosion potentials and current densities oscillate, possibly due to repeated tendencies of passivation and depassivation, and attainment of a totally protected state for Al may require secondary protection measures along with the use of zinc. Keywords: Atmospheric corrosion sensors, corrosion monitoring, silver reference electrode, thin film electrodes, passivation, cathodic protection of Al with Zn, corrosion tests, zinc coating on aluminum.
Electrochemical polarization data for the individual thin film electrodes Al and Zn as well as in galvanic couple connecting the two together have been generated using atmospheric corrosion sensors developed recently. Thin films of these metals were subjected to cyclic fog testing and to continuous immersion in selected electrolytes corresponding to atmospheric condensates and were tested also in actual atmospheric exposure under bold (totally open and subject to direct hit by rain and sun light) and sheltered (not hit by rain and sun light) conditions. Results generally indicate that zinc corrodes by very large amount tending to protect aluminum in the process. Aluminum corrodes by the least and remains passivated under test conditions involving only plain water. In the presence of chloride ion, pitting is activated, though zinc provides initial protection and tends to stabilize passivation. Under open bold conditions, zinc electrode experiences the largest corrosion current densities and passivates itself and Al remains also in the passive state. The potentials of both electrodes converge to nearly the same value around +100 mV measured against an open silver film. Under the sheltered locations, both the corrosion potentials and current densities oscillate, possibly due to repeated tendencies of passivation and depassivation, and attainment of a totally protected state for Al may require secondary protection measures along with the use of zinc. Keywords: Atmospheric corrosion sensors, corrosion monitoring, silver reference electrode, thin film electrodes, passivation, cathodic protection of Al with Zn, corrosion tests, zinc coating on aluminum.
PRICE BREAKS - The more you buy, the more you save
Quantity
1+
5+
Price
$20.00
$20.00
Product tags
Also Purchased
Picture for 99505 FLUORESCENT MATERIALS UTILIZED AS EARLY
Available for download

99505 FLUORESCENT MATERIALS UTILIZED AS EARLY WARNING SENSORS FOR CORROSION OF ALUMINUM ALLOY SURFACES

Product Number: 51300-99505-SG
ISBN: 99505 1999 CP
Author: Richard E. Johnson, Vinod S. Agarwala, Krishna S. Rajan, Alok Singh, Michael G. Durrett
$20.00
Picture for 99503 CORROSION - A “PEOPLE” PROBLEM
Available for download

99503 CORROSION - A “PEOPLE” PROBLEM

Product Number: 51300-99503-SG
ISBN: 99503 1999 CP
Author: Joseph Menke
$20.00
Picture for 99509 ELECTROCHEMICAL METHODS FOR MONITORING
Available for download

99509 ELECTROCHEMICAL METHODS FOR MONITORING PERFORMANCE OF CORROSION INHIBITOR UNDER MULTIPHASE FLOW

Product Number: 51300-99509-SG
ISBN: 99509 1999 CP
Author: Y. Chen and M. Gopal
$20.00
Categories
Industry
Recently viewed
Popular tags
View all

Association for Materials Protection and Performance

© AMPP All Rights Reserved.
Membership Terms of Content Use
Contact Customer Support