This specification covers the requirements for electrodeposited cadmium coatings on products of
iron, steel, and other
metals.
Note 1 — Cadmium is deposited as a coating principally on iron and
steel products. It can also be electrodeposited on aluminum, brass,
beryllium copper, copper, nickel, and powder metallurgy parts.
The coating is provided in various thicknesses up to and
including 25 µm either as electrodeposited or with supplementary finishes.
Cadmium coatings are used for corrosion resistance and
for corrosion prevention of the basis metal part. The asdeposited coating (Type I) is useful for the
lowest cost
protection in a mild or noncorrosive environment where early
formation of white corrosion products is not detrimental or
harmful to the function of a component. The prime purpose of
the supplementary chromate finishes (Types II and III) on the
electroplated cadmium is to increase corrosion resistance.
Chromating will retard or prevent the formation of white
corrosion products on surfaces exposed to various environmental conditions as well as delay the
appearance of corrosion from
the basis metal.
Cadmium plating is used to minimize bi-metallic corrosion between high-strength steel fasteners and
aluminum in the
aerospace industry. Undercutting of threads on fastener parts is
not necessary as the cadmium coating has a low coefficient of
friction that reduces the tightening torque required and allows
repetitive dismantling.
Cadmium-coated parts can easily be soldered without
the use of corrosive fluxes. Cadmium-coated steel parts have a
lower electrical contact resistance than zinc-coated steel. The
lubricity of cadmium plating is used on springs for doors and
latches and for weaving machinery operating in high humidity.
Corrosion products formed on cadmium are tightly adherent.
Unlike zinc, cadmium does not build up voluminous corrosion
4.1 Classes—Electrodeposited cadmium coatings shall be classified on the basis of thickness as follows:
| Class | Minimum Thickness, µm |
|---|---|
| 25 | 25 |
| 12 | 12 |
| 8 | 8 |
| 5 | 5 |
Nature of Coating—The coating shall be essentially15°C
pure cadmium produced by electrodeposition usually from an
alkaline cyanide solution.
High Tensile Strength Steel Parts— Steel parts having
an ultimate tensile strength greater than 1650 MPa (approximately 50 HRC) shall not be plated by
electrodeposition unless
authorized by the purchaser.
Stress Relief—Steel parts having an ultimate tensile
strength of 1050 MPa (approximately 35 HRC) and above, and
that have been machined, ground, cold-formed, or coldstraightened shall be heat-treated at 190 6 15°C
for 5 h or
more for stress relief before cleaning and coating.
Preparatory Procedures—The basis metal shall be subjected to such cleaning procedures as necessary
to ensure a
surface satisfactory for subsequent electroplating. Materials
used for cleaning shall have no damaging effects on the basis
metal resulting in pits, intergranular attack, stress corrosion
cracking, or hydrogen embrittlement. If necessary, cleaning
materials for steel parts should be evaluated in accordance with
Method F519.
Note 4 —For basis metal preparation, the following standards should be
employed depending upon the metallurgical composition: Practices B183,
B242, B253, B254, B281, B320, B322, B343 and B558.
Substrate—Cadmium shall be deposited directly on the
basis metal part without an undercoat of another metal except
when the part is either stainless steel or aluminum and its
alloys. An undercoat of nickel is permissible on stainless steel.
With aluminum and aluminum alloys, the oxide layer shall be
removed and replaced by a metallic zinc layer in accordance
with Guide B253. For better adherence, a copper strike or a
nickel coating may be applied to the zinc layer before
electroplating with the cadmium.
Plating Process—The plating shall be applied after all
basis metal heat treatments and mechanical operations, such as
machining, brazing, welding, forming, and perforating of the
article, have been completed.
Hydrogen Embrittlement Relief— Steel parts having a
tensile strength of 1200 MPa (approximately 38 HRC) and
higher shall be baked at 190 6 15°C for 8 h or more within 4
h after electroplating to provide hydrogen embrittlement relief.
Electroplated springs and other parts subject to flexure shall not
be flexed, loaded, or used before the hydrogen embrittlement
relief treatment. The baking treatment for hydrogen embrittlement relief shall be done before the
application of any
supplementary chromate treatment. When specified, freedom
from embrittlement shall be determined.
Note 5 —For high-strength steels, greater than 1300 MPa or approximately 40 HRC, it is
strongly
recommended that the baking time be
extended to 23h or more to ensure hydrogen embrittlement relief.
Note 6 — Electroplated steel parts, passivated by the baking operation
for hydrogen embrittlement relief, require reactivation before the chromate treatment. This application,
immersion in a dilute acid solution,
should be done as soon as practical. If the chromating solution contains
sulfuric acid, then the reactivating solution should be 1 part of sulfuric
acid (sp gr 1.83) by volume added to 99 parts of water. If the chromating
solution contains hydrochloric acid, then the reactivating solution should
be 1 part of hydrochloric acid (sp gr 1.16) by volume added to 99 parts of
water. Duration of immersion should be as brief as is consistent with the
nature of the work. Separately racked items can be reactivated in
approximately 5s, whereas a perforated container of barrel-plated parts
requires approximately 15 s.
Chromate Treatment:
Chromate treatments for Types II and III shall be done
in or with special aqueous acidic solutions composed of
hexavalent chromium along with certain anions that act as
catalyst or film-forming compounds to produce a continuous
smooth protective film. Chromic acid and nitric acid bright
dips shall not be used for treatment to produce chromate
coatings. When proprietary materials are used for this treatment, the instructions of the supplier
should be followed.
The Type II film color shall range from an iridescent
yellow or a thicker, more protective iridescent bronze or brown
to the heavier olive drab. It may also be dyed to a desired color.
When necessary, the color of the film shall be indicated by the
purchaser and specified by the provision of a suitably colored
sample or indicated on the drawing for the part.
The absence of color shall not be considered as
evidence of lack of Type III film or as a basis for rejection.
Presence of clear Type III film shall be determined by a spot
test as specified in 10.4.
Waxes, lacquers, or other organic coatings shall not be
used as a substitute for, nor may they be used in conjunction
with, supplementary treatments when the purpose is to ensure
conformance to the salt spray requirements. Waxes and the
like, may be used to improve lubricity.
Thickness:
The thickness of the coating everywhere on the
significant surfaces shall conform to the requirements of the
specified class, as defined in 4.1.
Significant surfaces are those normally visible (directly or by reflection) that are essential to
the appearance or
serviceability of the article when assembled in normal position;
or that can be the source of corrosion products that will deface
visible surfaces on the assembled article. When necessary, the
significant surfaces shall be indicated by the purchaser on
applicable drawing of the article, or by the provision of
suitably marked samples.
Note 7 — As heavier coatings are required for satisfactory corrosion
resistance than Class 5, allowance should be made in the fabrication of
most threaded articles, such as nuts, bolts, and similar fasteners with
complementary threads for dimensional tolerances to obtain necessary
coating build-up. Flat surfaces and certain shielded or recessed areas, such
as root-diameter of threads, have a tendency to exhibit lack of build-up
and to be heavier at exposed edges and sharp projections with electrodeposited coatings. This trend is
also found with vacuum-deposited cadmium coatings and is in direct contrast with mechanically deposited
coatings.
NOTE 8 — The coating thickness requirements of this specification is a
minimum requirement. Variation in thickness from point to point on an
article is inherent in electroplating. Therefore, the thickness will have to
exceed the specified value at some points on the significant surfaces to
ensure that it equals or exceeds the specified value at all points. Hence, in
most cases, the average coating thickness of an article will be greater than
the specified value; how much greater is largely determined by the shape
of the article (see Practice B507) and the characteristics of the
electroplating process. In addition,
the average coating thickness on articles will
vary from article to article within a production lot. Therefore, if all of the
articles in a production lot are to meet the thickness requirement, the
average coating thickness for the production lot as a whole will be greater
than the average necessary to assure that a single article meets the
requirement.
For nonsignificant visible surfaces, the minimum
thickness for Classes 25 and 12 shall be Class 8 (8 µm); for
Class 8 it shall be Class 5 (5 µm); and for Class 5 it shall be 4
µm.
Adhesion — The cadmium coating shall be sufficiently
adherent to the basis metal to pass the tests detailed in 10.2.
Abrasion Resistant—The supplementary Type II chromate film shall be adherent, nonpowdery, and
abrasion resistant
(10.3).
Corrosion Resistance—Cadmium coatings with supplementary chromate films on iron and steel basis
metals shall
show neither white corrosion products of cadmium nor basis
metal corrosion products at the end of 96 h for Type II film or
12 h for Type III film when tested by continuous exposure to
salt spray. The appearance of corrosion products visible to the
unaided eye at normal reading distance shall be cause for
rejection, except white corrosion products at the edges of
specimens shall not constitute failure.
Note 9 —The hours given are the minimum required to guarantee
satisfactory performance. Longer periods before the appearance of white
corrosion and basis metal corrosion (rust from iron and steel products) are
possible. Salt spray resistance does not vary in exact proportion with
increased plating thicknesses of Types II and III coatings. Although
specified hours to failure (red rust for iron and steel articles) for Type I
coating is not stated, the hours given for Types II and III reflect the added
protection of the chromate treatment without requiring impractical testing.
Note 10 — In many instances, there is no direct relation between the
results of an accelerated corrosion test and the resistance to corrosion in
other media. Factors such as the formation of protective films, basis
materials, and temperature can influence the progress of corrosion greatly,
depending upon the conditions encountered in service. The results
obtained in the test should, therefore, not be regarded as a direct guide to
the corrosion resistance of the tested materials in all environments where
these materials may be used. Also, performance of different materials in
the test cannot always be taken as a direct guide to the relative corrosion
of these materials in service.
Luster—Either a bright or dull luster shall be acceptable; however, for steel parts that are heat
treated to 40 HRC
(approximately 1300 MPa) and harder, they shall have a dull
luster or finish.
Note 11 — High-strength steel parts that are cadmium plated from baths
without brighteners are much more permeable to hydrogen than those
bright cadmium plated. Bright cadmium is a very good hydrogen barrier
that “seals in” the hydrogen. As embrittlement is a surface or subsurface
phenomenon, even a 24h baking is not sufficient to provide embrittlement
relief of high-strength steels plated with a Class 12 deposit from a bright
cyanide plating bath.
Workmanship and Finish—The coating shall be smooth,
adherent, uniform in appearance, and free from blisters, pits,
nodules, flaking, and other defects that may affect the function
of the coating. The coating shall cover all surfaces as stated in
7.1, including thread roots, thread peaks, corners, holes,
recesses, and edges. There shall be no indication of contamination or improper operation of equipment
used to produce the
deposit, such as excessively powdery or darkened coatings.
Superficial staining and variations in color or luster shall not be
cause for rejection. Defects and variations in appearance of the
coating that arise from surface conditions of the substrate
(pores, scratches, roll marks, inclusions, and the like) and that
persist in the finish despite the observance of good application
techniques shall not be cause for rejection.
Note 12 — Coatings generally perform better in service when the
substrate over which they are applied is smooth and free from torn metal,
inclusions, pores, and other defects. The specifications covering the
unfinished product should provide limits for these defects. A metal finisher
can often remove defects through special treatments such as grinding,
polishing, electropolishing, and chemical treatments. However these are
not normal in the treatment steps preceding the application of the coating.
When desired, they are subject of a special agreement between the
purchaser and supplier.
Inspection Lot—An inspection lot shall be a collection
of coated articles that are of the same kind, that have been
produced to the same specifications, that have been coated by
a single supplier at one time or at approximately the same time
under essentially identical conditions, and that are submitted
for acceptance or rejection as a group.
Selection — A random sample of the size required by
Test Method B602 shall be selected from the inspection lot.
The articles in the lot shall be inspected for conformance to the
requirements of this specification and the lot shall be classified
as conforming to or nonconforming to each requirement in
accordance with the criteria of the sampling plan in Test
Method B602.
Note 13 —Test Method B602 contains four sampling plans,
three of
which are to be used with nondestructive test methods, the fourth is to be
used with destructive test methods. The three methods for nondestructive
tests differ in the quality level they require of the product. Test Method
B602 requires use of the plan with the intermediate quality level unless
the purchaser specifies otherwise. It is recommended that the purchaser
compare the plans with his needs and state which plan is to be used. If the
plans in Test Method B602 do not serve the needs, additional plans are
given in Guide B697. Both Method B602 and Guide
B697 list references
where additional information on sampling inspection and additional plans
are given.
Note 14 — When both destructive and nondestructive tests exist for the
measurement of a characteristic, the purchaser needs to state which is to
be used so that the proper sampling plan is selected. Whether or not a test
is destructive may not always be clear. A test may destroy the coating, but
in a noncritical area; or, although it may destroy the coating, a tested piece
can be reclaimed by stripping and recoating. The purchaser needs to state
whether the test is to be considered destructive or nondestructive. The
decision is important because the plans for destructive tests are significantly less able to
discriminate between acceptable and unacceptable lots.
This is because fewer parts are tested using this plan.
Specimens—If separate test specimens are to be used to
represent the coated articles in a test, the specimens shall be of
the nature, size, and number and shall be processed as required
in 9.1, 9.2, 9.3, 9.4, Supplementary Requirement S2, or in the
purchase order.
Electroplated Parts or Separate Specimens—When the
electroplated parts are of such form, shape, size, and value as
to prohibit use, or are not readily adaptable to a test, or when
destructive tests of small lot size are required, the test shall be
made by the use of separate specimens electroplated concurrently with the articles represented. The
permission or the
requirement to use test specimens, their number, the material
from which they shall be made, and their shape and size shall
be stated in the purchase order or other governing document.
The separate specimens shall be of a basis metal equivalent to
that of article represented, of the same metallurgical condition,
and shall have the same surface condition. These separate
specimens shall be introduced into the lot at regular intervals
before the cleaning operation, preliminary to electroplating,
and shall not be separated therefrom until after completion of
the electroplating. Conditions affecting the electroplating of
specimens, including the spacing, plating media, bath agitation,
temperature, etc., in respect to the other objects being electroplated, shall correspond as nearly as
possible to those affecting
the significant surfaces of the articles represented. Unless a
need can be demonstrated, separately prepared specimens shall
not be used in place of production items for nondestructive and
visual examinations.
Thickness, Adhesion, Abrasion Resistance and Presence
of Clear (Type III) Coating Specimens—If separate specimens
for thickness, adhesion, abrasion resistance, and the presence
of clear (Type III) coating tests are required, they shall be strips
approximately 100 mm long, 25 mm wide, and 1 mm thick, or
cylindrical pieces with the cross-section area approximately
equal to that of the production item.
Corrosion Resistance Specimens — If separate specimens for the corrosion resistance test are required,
they shall be
panels, approximately 150 mm long, 100 mm wide, and 1 mm
thick.
Hydrogen Embrittlement Relief Specimens—If separate
specimens are required for the hydrogen embrittlement relief
test, the configuration shall be specified by the purchaser.
Note 15 —When required for testing, the manufacturer of the basis
metal parts should provide the coating facility with the stated test
specimens, loading bolts, loading rings, and the like
Thickness:
The thickness of electrodeposited cadmium coatings
shall be determined by Test Methods B 487, B 499, B504,
B567, or B568, as applicable. Other methods may
be used, if
it can be demonstrated that the uncertainty of measurements
with these methods is less than 10%.
The thickness measurements of Types II and III
deposits shall be made after application of the supplementary
treatments. Whenever Test Method B504 or B567 is
used,
remove the supplementary treatment from the test area before
measuring the thickness. Remove by using a mild abrasive (a
paste of levigated alumina or magnesium oxide) and rubbing
gently with the finger.
Adhesion—The electrodeposited cadmium coating
shall be tested for adhesion to the basis metal or substrate layer
in a manner that is consistent with the service requirements of
the coated article. When examined at a magnification of
approximately 43 diameters, the coating shall not show
separation at the interface. The formation of cracks in the
coating caused by rupture of the basis metal that does not result
in flaking, peeling, or blistering of the coating shall not be
considered as nonconformance. Use one of the following
methods for determining adhesion.
The surface of the coated article shall be scrapped or
sheared with a sharp edge, knife, or razor blade through the
coating down to the basis metal and examined at 43 magnification for evidence of nonadhesion.
The part shall be plastically deformed, if possible, by
clamping in a vise and bending the projecting portion back and
forth until rupture occurs.
Any suitable test procedure, such as the burnishing
test, the draw test, the peel test, or the scribe test in accordance
with Test Methods B571 shall be used.
Note 16 —There is no single satisfactory test for evaluating the
adhesion of electrodeposited coatings. Those given (10.2.1, 10.2.2, and
10.2.3) are widely used; however, other tests may prove more applicable
in special cases.
Abrasion Resistance—The abrasion resistance of the
supplementary chromate films (Types II and III) shall be
determined in accordance with Practice B201.
Clear (Colorless) Type III Coatings—The presence of
a clear Type III coating shall be determined in accordance with
Practice B201.
Salt Spray Corrosion Resistance—The 5% neutral salt
spray (fog) test as defined in Test Method B 117 shall be used
when there is a steel or iron substrate. Parts with supplementary chromate film shall be aged at room
temperature for at
least 24 h before subjection to the test.
Hydrogen Embrittlement—The test to indicate freedom
from hydrogen embrittlement failure of coated parts or specimens need not be conducted unless the
method is specified in
the purchase order. The method description shall include
specimen configuration, means of applying a load to the part,
stress or load level, and duration of test. Parts shall not crack
or fail by fracture when tested.
Visual Examination—The coating shall be examined
for compliance with the requirements of luster, workmanship,
and finish.
Coatings that fail to conform to the requirements of this specification or authorized modifications may be rejected. They may be reconsidered for acceptance by rectifying inspection in accordance with Methods B602 and B697 when allowed by the purchaser. Rejection should be reported to the producer or supplier promptly and in writing. In case of dissatisfaction with the results of the test, the producer or supplier may make claims for a rehearing. Coatings that show imperfection during subsequent manufacturing operations may be rejected.
When specified in the purchase order or contract, the producer’s or supplier’s certification shall be furnished to the purchaser stating that samples representing each lot have been processed, tested, and inspected in accordance with this specification and the requirements have been met. When specified in the purchase order or contract, a report of the test results shall be furnished.
Preservation, packaging and packing methods for electrodeposited cadmium parts or articles employed by a supplier shall be such as to preclude damaging during shipment and handling.
cadmium; electrodeposited coatings; electrodeposited coatings; cadmium
The following supplementary requirements shall apply only when specified by the purchaser in the
contract or order and for all agencies of the United States Government.
S1. Responsibility for Inspection
The producer or supplier shall be responsible for the
performance of all inspection requirements as specified herein.
Except as otherwise specified in the contract or order, the
supplier may use his own or any other facilities suitable for the
performance of the inspection requirements specified herein
unless disapproved by the purchaser. The purchaser retains the
right to perform any of the inspections and tests set forth in this
specification where such inspections and tests are deemed
necessary to ensure that the supplies and services conform to
the prescribed requirements.
S2. Specimens for Hydrogen Embrittlement Relief
Four specimens shall be used to represent the lot. The
specimens for the test shall be round notched specimens with
the axis of the specimen (load direction) perpendicular to the
short transverse grain flow direction. The configuration shall be
in accordance with the figure pertaining to 12.7 6 0.025 mm
(0.5 6 0.001 in.) round tension test specimens with 50.8 6
0.13 mm (2.0 6 0.05 in.) gage length and examples of
small-size specimens proportional to the standard specimen in
Method E8.Specimens shall have a 60 6 1° V-notch located
approximately at the center of the gagelength. The cross
section area at the root of the “V” shall be approximately equal
to half the area of the full cross-section area of the specimen’s
reduced section. The “V” shall have a 0.254 6 0.013 mm
radius of curvature at the base of the notch.
S3. Embrittlement Relief Test
The notched specimens shall be subjected to a sustained tensile load equal to 75 6 2 % of the
ultimate notch
tensile strength of the material. The articles, parts, or specimens shall be held under load for at
least 200h and then
examined for cracks or fracture.
Parts such as spring pins, lock rings, and the like, that
are installed in holes or rods shall be similarly assembledusing
the applicable parts specifications or drawing toler-ances which
impose the maximum sustained tensile load on the plated part.
The selected samples shall be subjected to a sustained tensile
load equal to 115 % of the maximum design yield load for
which the part was designed. Fastener hardware, where the
maximum yield load is not known or given, shall be tested in
accordance with MIL-STD 1312, Test 5. Parts that require
special fixtures, extreme loads to comply with the above
requirements, or where the maximum design yield load is not
known, may be represented by separate notched specimens.
Note S00017 — The manufacturer of the basis metal parts should
provide the coating facility with notched tensile specimens when required
for testing.
X1. Electrodeposited Cadmium Coating
Use—Electrodeposited cadmium coatings, mainly on
iron and steel products, are widely used in many industries.
Electrodeposition of the cadmium on other metal products
being used to a greater extent in both the aerospace and
communication industries. The corrosion rate of cadmium
plated parts is much lower than that of unplated parts in most
atmospheres as well as in water. In addition, the electrochemical relationship between cadmium and a
basis metal, for
example, steel, is such that the corrosion or rusting is suppressed by galvanic action even where the
cadmium coating
may be damaged or worn through. The Type I, as-deposited
coating, may be used to improve solderability, to lower
electrical contact resistance, to provide surface conductivity on
electronic equipment, and to prevent seizing of moving parts,
bolts, nuts, and latches.
X1.2 Limitations—The Type I electrodeposited coatings
should not be used on production items that in service will
reach a temperature of 225°C or higher or will come in contact
with other parts that reach these temperatures. Cadmium
coated parts that may be subjected to heat from soldering,
brazing, or welding operations should be so labeled and tagged
to indicate being so coated because of the danger from
poisonous cadmium oxide vapors during these operations.
X2. Supplementary Treatments
Purpose—The clear chromate film (Type III) is
generally used to prevent fingermarkings and corrosion of parts
that may occur at room temperature during assembly and
storage or will be exposed to a mild environmental condition.
The purpose of the colored chromate supplementary finish
(Type II) on cadmium coatings is to retard the weathering to
form white corrosion products on the surfaces exposed to
stagnant water, sea water, marine atmospheres, high humidity,
or cyclic condensation and drying. Most of the iridescent
yellow to live drab Type II chromate films will be satisfactory
as an undercoat if production items are to receive an organic
paint system application, as generally required by the aerospace industry.
Limitations—Supplementary chromate treatments
should not be applied to production items that will not be
painted and will be continuously exposed to temperatures in
excess of 65°C or intermittently exposed for short periods to a
temperature of about 150°C. The protective value of the
supplementary coating decreases under these conditions. Temperatures above 65°C will accelerate the
deterioration of the
chromate film especially in drier environments, such that the
chromate coating can become so powdery that no protection is
provided.
Handling Precautions—Chromate treated articles that
involve only dipping in chemical solutions normally require 24
h at 20 to 30°C to render them suitable for handling without
damage to the finish coating while the latter is in the gelatinous
form. It is important with such coatings that the supplement
film is not damaged while wet in order to comply with the
workmanship requirements.
X3. Service Conditions
The service life of a cadmium coating, based upon
atmospheric exposure tests, has supported the generalization
that the protective value of the deposit is proportional to its
thickness and to the environment to which it is exposed.
Conditions of exposure and basis metals are so varied that it is
not possible to predict the exact service life of a coating of a
given thickness, with or without a supplementary finish. Table
provides recommended thicknesses with a supplementary
finish on typical applications (mainly iron and steel articles)
that are suitable under certain service conditions.
Service Life and Conditions
| Service Condition | Class | Treatment | Exposure | Typical Applications |
|---|---|---|---|---|
| Severe | 25 A or 12 | Type II | To condensation, perspiration, infrequent wetting by rain, cleaners | Military hardware, electronic parts for tropical service, washing machinery |
| Moderate | 8 | Type II | Mostly to dry indoor atmospheres but subjected to occasional condensation, wear, or abrasion | Threaded parts, screws, bolts, radio parts instruments, TV, and radio chassis |
| Mild | 5 | Type II or Type III | Indoor atmospheres and with rare condensation and subject to minimum wear or abrasion | Springs, locks, washers, tools, fasteners, electronic and electrical parts |
| Specification B 766 | Specification A165 | ||
|---|---|---|---|
| Class | Thickness, µm | Type | Thickness, µm |
| 25 | 25 A | NS | 12 |
| 12 | 12 | OS | 8 |
| 8 | 8 | TS | 5 |
| 5 | 5 | ||
| Supplementary Finish: | Supplementary Finish: Type: Not Specified | ||
| I None, as deposited II With a colored chromate treatment III With a colorless chromate treatment |
|||
| Specification QQ-P-416 | Specification ISO 2082 | |||
|---|---|---|---|---|
| Class | Thickness, in. (µm): | Service Condition | Class | Thickness, µm: |
| 1 | 0.0005(13) | 3 | Fe/Cd25c | 25 |
| 2 | 0.0003 (8) | 2 | Fe/Cd12c | 12 A |
| 3 | 0.0002 (5) | 1 | Fe/Cd5c | 5 |
| Supplementary Finish: | Supplementary Finish: | |||
| Type: I None, as deposited II With chromate treatment (colored) III With phosphate treatment be painted. |
||||
| 25 | 25 A | NS | 12 | |
| 12 | 12 | OS | 8 | |
| 8 | 8 | TS | 5 | |
| 5 | 5 | |||
| Supplementary Finish: | Supplementary Finish: Type: Not Specified | |||
| I None, as deposited II With a colored chromate treatment III With a colorless chromate treatment |
Not as a requirement, but stated a colored or colorless coating shall be applied unless otherwise specified. Phosphating may be used as alternate treatment for articles to be painted. | |||
The following standards form a part of this document to
the extent referenced herein.
ASTM Standards:
A165 Specification for Electrodeposited Coatings of Cadmium on
Steel2
B117 Practice for Operating Salt Spray (Fog) Apparatus3
B183 Practice for Preparation of Low-Carbon Steel for
Electroplating4
B201 Practice for Testing Chromate Coatings on Zinc and
Cadmium Surfaces4
B242 Practice for Preparation of High-Carbon Steel for
Electroplating4
B253 Guide for Preparation of Aluminum Alloys for Electroplating4
B254 Practice for Preparation of and Electroplating on
Stainless Steel4
B281 Practice for Preparation of Copper and Copper-Base
Alloys for Electroplating and Conversion Coatings4
B320 Practice for Preparation of Iron Castings for Electroplating4
B322 Practice for Cleaning Metals Prior to Electroplating4
B343 Practice for Preparation of Nickel for Electroplating
with Nickel4
B374Terminology Relating to Electroplating4
B487 Test Method for Measurement of Metal and Oxide
Coating Thicknesses by Microscopical Examination of a
Cross Section4
B499 Test Method for Measurement of Coating Thicknesses by the Magnetic
Method: Nonmagnetic Coatings
on
Magnetic Basis Metals4