ARMY
TM 5-6115-612-34
NAVY
AG-320B0-MME-000
b
Applicable Documents The latest Issue of
Aerospace Material Specifications (AMS) shall apply
(1)
Engineering Process Specifications
Vapor degreasing (Item 4, appx B)
Grit blasting (Item 3, appx B)
Acid cleaning (item 2, appx B)
(2)
Engineering Materials Specifications
Nickel-aluminum composite powder
(item 8, appx B)
Solvent, petroleum (Item 5, appx B)
c
Requirements
(1)
Equipment An approved metalizing gun
designed to provide automatic gas pressure and powder
feed control
(2)
Coating Materials Coating materials shall
be an approved nickel-aluminum composite powder
(item 8, appx B)
d
Procedure
(1)
Cleaning
WARNING
Toxic solvent Is used for general cleaning Illness or
skin damage may be caused by prolonged
breathing of solvent fumes or excessive skin
contact with the liquid Ensure there is adequate
ventilation and avoid open flame or sparks when
using flammable solvent
(a)
Titanium Base Parts shall be cleaned
by washing in petroleum solvent (item 4, appx B) or by
wiping with a clean, lint-free rag (item 7, appx B)
dampened with keytone (Item 9, appx B)
NOTE
No cleaner or solvent shall be used that will
introduce excessive chlorides or halides onto the
surface of titanium pans
(b)
Aluminum Base Parts or Steel Parts
Parts shall be thoroughly cleaned free from dirt, grease,
oil or otherforeign materials by vapor degreasing or by
washing In petroleum solvent (item 4, appx B)
(2)
Masking Parts shall be masked as required
to protect areas not designated to be coated Masks may
be steel, brass, or other suitable materials properly
protected against adherence by the sprayed coating
(3)
Surface Conditioning Grit blast the masked
parts sufficiently to remove all metallic luster Excessive
blasting shall be avoided
(a)
Titanium base parts Surfaces shall be
etched to roughen the surfaces and provide adequate
adhesion of the sprayed coating
(b)
Aluminum base alloy or steel parts
Surfaces shall be prepared by immersion In suitable
solutions to roughen the surfaces and provide adequate
adhesion of the sprayed coating
(c)
Care must be taken to prevent
contamination of the prepared surfaces by contact or
other means If necessary to handle the prepared part,
clean lint-free gloves (item 6, appx B) must be used
Parts shall be spray coated as soon as possible but In no
case longer than 2 hours after surfaces have been
prepared for coating.
(d)
Wipe grit blasted surfaces with clean,
lint-free rag (item 7, appx B) dampened with acetone
(item 1, appx B) or other suitable solvent just prior to
spraying.
(4)
Spray Coating
(a)
Place part in fixture designed to permit
uniform coverage of areas designated to be coated
Proper ventilation is required to remove over-spray and
non-adherent particles
(b)
Preheat cleaned and masked part to
175-200° F (79-93° C)
(c)
Spray the nickel-aluminum composite
coating (item 8, appx B) onto designated surfaces to a
thickness sufficient to meet bond coat re- quirements or,
on salvage areas, to meet specified thickness
requirements after finish machining
(d)
The spray composite must Impinge on
the surface to be coated at an angle of 75-105 degrees
(1 31-1 83 radians).
(e)
Remove masking In a manner that will
avoid damage to the sprayed coating
14-4 Change 4