NOTE: One pound of sodium bicarbonate in 1 gallon of water will give the
desired mixture.
D. Continue to apply the solution until bubbles cease. Then allow the solution
to remain on the surface for an additional 5 minutes.
E. Remove the neutralized mixture with a mop or sponge.
F. Rinse the affected area with generous quantities of clean water. Occasion-ally agitate the surface with a soft brush.
G. Neutralization of the alkaline fluid should be determined with litmus paper.
H. Wipe dry with clean cloths.
I. After thoroughly drying, repair or replace damaged finishes if at all possi-ble. Refer to 20-50-00 and 20-60-00 for protective finish systems.
J. Apply BMS 3-23 water displacing corrosion inhibiting compound over the
entire area.
Volume 1
20-44-00
Page 2
OCT 01/01
CORROSION PREVENTION MANUAL
GENERAL INFORMATION STANDARD TREATMENT METHODS
1. General
A. In order to preclude the occurrence or recurrence of corrosion after corro-sion removal or corrosion damage repair, the exposed surfaces of most metals
must be immediately treated after rework. These treatments include conver-sion coating, plating or the application of thin protective film, i.e., oil
or primer, over the base metal. The conversion coatings and primer applica-tion also enhance the surface adhesion qualities for painting, if required.
Some metals, such as stainless steel and titanium, which are basically cor-rosion resistant do not require surface protection except for painting to
match the surrounding structure, or in dissimilar metal applications when
plating, painting or sealing becomes necessary.
B. Corrosion Prevention. Although the surface finish has been restored by the
treatment methods in this section to minimize the recurrence of corrosion,
service experience indicates it would be advantageous to apply a corrosion
inhibiting compound over the surface finish in the more susceptible areas.
Refer to the applicable sections of Volume 2.
2. Surface Treatment for Aluminum and Aluminum Alloys
A. General. Aluminum and its alloys quickly forms an invisible protective oxide
film on the surface when exposed to atmosphere. The oxide will provide cor-rosion protection in mild environment, but since the reworked area is in a
corrosion prone area further protection is required.
B. Surface Treatment. All aluminum surfaces that have been reworked per 20-40-00 or applicable methods in Volume 2 should be cleaned and have a conversion
coating applied. The coating materials chemically convert the aluminum sur-face into a very thin (0.00001 to 0.0005 inch) non-metallic chromated film
as an integral part of the metal. This film is resistant to corrosion and an
excellent adherent for subsequent priming. The conversion coating can be
applied by alodizing or by Iridite treatment. Solutions used in both treat-ments are proprietary but are readily available through most sources han-dling chemicals. There are several alodizing chemicals and the treatment
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