ASTM B254.pdf
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Designation: B 254 – 92 (Reapproved 2004)
e1
Endorsed by American
Electroplaters’ Society
Endorsed by National Associa-
tion of Metal Finishers
Standard Practice for
Preparation of and Electroplating on Stainless Steel
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This standard is issued under the fixed designation B 254; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
e
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NOTE—Warning note updated in Section 7.3 in May 2004.
1. Scope
1.1 Various metals are electrodeposited on stainless steel for
color matching, lubrication during cold heading, spring-coiling
and wire-drawing operations, reduction of scaling at high
temperatures, improvement of wettability (as in fountain pens),
improvement of heat and electrical conductance, prevention of
galling, jewelry decoration, and prevention of superficial
rusting.
1.2 This practice is presented as an aid to electroplaters and
finishing engineers, confronted with problems inherent in the
electrodeposition of metals on stainless steel. It is not a
standardized procedure but a guide to the production of smooth
adherent electrodeposits on stainless steel.
1.3 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
2. Referenced Documents
2.1 ASTM Standards:
2
A 380 Practice for Cleaning, Descaling, and Passivation of
Stainless Steel Parts, Equipment, and Systems
3. Nature of Stainless Steel
3.1 Because previous metal treatment may have a more
pronounced effect on the final finish when stainless steel is
being electroplated, the metal finisher should become ac-
quainted with the fabrication procedure, grade, and mill finish
of the stainless steel with which he is working before outlining
his electrodeposition procedure (see Appendix X1).
3.2 Stainless steel surfaces are normally resistant to a wide
variety of corrosive elements. This property is the result of a
thin transparent film of oxides present on the surface. Because
this film rapidly reforms after it has been stripped off or
penetrated, it protects stainless steel against corrosion. An
adherent electrodeposit cannot be obtained over the oxide film
normally present on stainless steel. However, once this film is
removed by surface activation and kept from reforming while
the surface is covered with an electrodeposit, any of the
commonly electroplated metals may be electrodeposited suc-
cessfully on stainless steel.
3.3 Where the finished product is to be subjected to severe
exposure, the deposit produced by the proposed electroplating
sequence should be tested under similar exposure conditions
before adoption, to determine whether the natural corrosion
resistance of the stainless steel has been impaired by the
presence of the electrodeposit.
4. Nature of Cleaning
4.1 The preparation of stainless steel for electroplating
involves three basic steps in the following order:
4.1.1 Removal of scale. If scale removal is necessary, one of
the methods outlined in Appendix X2 may be used (Note 1).
See also Practice A 380.
4.1.2 Removal of oil, grease, or other foreign material by
cleaning, and
4.1.3 Activation immediately before electroplating.
4.2 Precleaning—Removal of fabricating lubricants and
finishing compounds from the stainless steel may have to be
undertaken immediately following the fabrication or finishing
operation (Note 2).
4.3 Electrocleaning—Anodic cleaning is generally pre-
ferred (Note 3).
4.4 Metal Lubricants—Metal lubricants such as copper,
lead, or cadmium, applied to stainless steel wire for cold
heading, wire drawing, or spring forming are removed by
immersion in a solution of 200 mL of concentrated, 67 mass %,
nitric acid (density 1.40 g/mL) diluted to 1 L at 50 to 60°C. See
Practice A 380.
NOTE 1—Oil, grease or other fabricating lubricants should be removed
by cleaning before heat treating.
N
OTE 2—Spray cleaning with a nozzle pressure of 200 to 400 kPa (30
to 60 psi) in a power washer, using an alkaline or emulsion-type cleaner,
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This practice is under the jurisdiction of ASTM Committee B08 on Metallic
and Inorganic Coatings and is the direct responsibility of Subcommittee B08.02 on
Pre Treatment.
Current edition approved April 1, 2004. Published May 2004. Originally
approved in 1951. Last previous edition approved in 1998 as B 254–92 (1998).
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
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