ASTM B319-91(2014)

Standard Guide for Preparation of Lead and Lead Alloys for Electroplating

SIGNIFICANCE AND USE
3.1 The preparation of lead and lead-alloy surfaces for electroplating is often critical to the successful performance of electrodeposited and autocatalytic metallic coatings.  
3.2 This standard outlines the process operation procedures and processing solutions required, that lead to satisfactory electrodeposited metallic coatings (including undercoating) on surfaces of lead and lead-alloys.
SCOPE
1.1 This guide provides methods for preparing lead or lead alloy products for the application of electroplated or autocatalytic coatings.  
1.2 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 appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-Oct-2014
• ICS: 25.220.40 - Metallic coatings
• Technical Committee: B08 - Metallic and Inorganic Coatings
• Drafting Committee: B08.02 - Pre Treatment

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: B319 − 91 (Reapproved 2014) Endorsed by American
Electroplaters’ Society
Endorsed by National
Association of Metal Finishers
Standard Guide for
Preparation of Lead and Lead Alloys for Electroplating
This standard is issued under the fixed designation B319; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope 4.2.1 The very active chemical nature of lead, leading to the
formation of oxide films in air,
1.1 This guide provides methods for preparing lead or lead
4.2.2 The fact that the lead surface will form films of
alloy products for the application of electroplated or autocata-
insoluble lead salts with most acids used in pickling,
lytic coatings.
4.2.3 The ease with which lead diffuses in contact with
1.2 This standard does not purport to address all of the
nonferrous metals, and
safety concerns, if any, associated with its use. It is the
4.2.4 The poor resistance to plastic deformation during
responsibility of the user of this standard to establish appro-
polishing.
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
5. Process Precautions
2. Referenced Documents
5.1 The following process precautions should be observed:
2.1 ASTM Standards:
5.1.1 Precleaning of raw castings is sometimes necessary to
B281 Practice for Preparation of Copper and Copper-Base
remove mold parting compounds, surface oxides, and residues
Alloys for Electroplating and Conversion Coatings
from recessed areas which are never reached by polishing-
wheel or scratch-brush operations (Section 6).
3. Significance and Use
5.1.2 In high-speed type cyanide electroplating solutions,
3.1 The preparation of lead and lead-alloy surfaces for
the initial current density must be controlled and kept low
electroplating is often critical to the successful performance of
enough so that no gassing occurs to cause poor adhesion. This
electrodeposited and autocatalytic metallic coatings.
is revealed as groups of blisters in the high-current-density
areas of the electroplate.
3.2 This standard outlines the process operation procedures
5.1.3 If a strike electroplate is used, it should be thick
and processing solutions required, that lead to satisfactory
enough to prevent the next electroplating solution from attack-
electrodeposited metallic coatings (including undercoating) on
ingthebasislead.Acopperornickelstrike2.5µmthickshould
surfaces of lead and lead-alloys.
be used, but because there are so many variables involved, no
4. Nature of Lead specific recommendations can be made.
5.1.4 Preplates should be of such thickness that complete
4.1 The tensile strength of lead and lead alloys ranges from
alloying with the lead does not take place, an occurrence that
15 to 35 MPa (2000 to 5000 psi), therefore, the measured
causes poor adhesion of subsequent deposits. This defect is
adhesion of electroplated coatings cannot be greater than these
indicated by blistering after prolonged storage or after an
values.
accelerated aging test.
4.2 Difficulties in applying high-quality electroplated coat-
5.1.5 Theleadcompoundsformedbytheactionofacidsand
ings to lead are due to the following properties of lead:
alkalies most often used in electroplating are not water soluble.
Caution must be taken to remove or prevent the formation of
This guide is under the jurisdiction of ASTM Committee B08 on Metallic and these to eliminate subsequent adhesion failure. Acids that
Inorganic Coatings and is the direct responsibility of Subcommittee B08.02 on Pre
cannot be used are sulfuric, hydrochloric, and hydrofluoric.
Treatment.
(Acids that can be used are sulfamic and fluoboric.) Alkalies
Current edition approved Nov. 1, 2014. Published November 2014. Originally
should not be high in caustic content. Mild or buffered cleaners
approvedin1957.Lastpreviouseditionapprovedin2009asB319 – 91(2009).DOI:
10.1520/B0319-91R14.
are preferred in order to minimize attack on the basis lead
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
surface.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
5.1.6 Engraving of electroplated finishes on lead cannot be
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. performed on deposits over 5 µm thick as the deposit will tear
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
B319 − 91 (2014)
away from the lead at cross cuts. Engine turning by burnishing the lead and is used sometimes in industrial or special
can be done on any thickness of deposits. applications if stressed or distorted surface layers must be
5.1.7 Polishing and coloring of the deposit must be per- removed to expose the natural understructure.
formed at slow speeds, and with loose or cooled buffs to 9.2.2 There are proprietary cleaners designed for special
eliminate overheating and flowing of basis metal. conditions;however,acleanermadeupusing23g/Lofsodium
carbonate and 23 g/L of trisodium orthophosphate, anhydrous
6. Precleaning
operated at 60 to 80°C with 6 to 8Vwith the work cathodic for
6.1 Removefinsandpartinglinesbyuseoftrimmingdiesor 30 to 60 s is advantageous. Hand cleaning by mopping and
brushing is performed, but the trend is away from hand
by scraping, filing, or grinding. Some machining may be done
at this point, such as drilling holes, or milling or cutting slots, operations.
groove, flats, or squared surfaces.
9.3 Acid Pickle:
6.2 Clean in alkaline, emulsion type, or other standard 9.3.1 An acid pickle of one of the following types is used to
remove all oxide residues and insoluble compounds left from
cleaning material to remove surface materials (5.1.5).
cleaning:
6.3 After rinsing, transfer the parts into one of the following
9.3.1.1 Anaqueoussolutioncontaining120to250mLof48
pickling solutions, the function of which is to remove surface
mass % fluoboric acid diluted to 1 L used at 20 to 25°C for 30
oxides, without significant attack on the lead surface.
to 60 s. See Practice B281.
6.3.1 Anaqueoussolutioncontaining250mLof48mass %,
9.3.1.2 An aqueous solution containing 100 g of sulfamic
fluoboric acid with or without 45 mL of 30 mass % hydrogen
acid dissolved in water and diluted to 1 L used at 20 to 25°C
peroxidedilutedto1L.Theadditionofhydrogenperoxidewill
for 30 to 60 s. A blend of 75 to 85 % by weight sulfamic acid
increase the aggressiveness of the pickling solution.
and 15 to 25 % by weight ammonium bifluoride may be
6.3.2 An aqueous solution containing 80 mL of glacial
dissolved in water at 60 to 120 g/L to form an e
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: B319 − 91 (Reapproved 2009) B319 − 91 (Reapproved 2014) Endorsed by American
Electroplaters’ Society
Endorsed by National
Association of Metal Finishers
Standard Guide for
Preparation of Lead and Lead Alloys for Electroplating
This standard is issued under the fixed designation B319; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This guide provides methods for preparing lead or lead alloy products for the application of electroplated or autocatalytic
coatings.
1.2 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 appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2.1 ASTM Standards:
B281 Practice for Preparation of Copper and Copper-Base Alloys for Electroplating and Conversion Coatings
3. Significance and Use
3.1 The preparation of lead and lead-alloy surfaces for electroplating is often critical to the successful performance of
electrodeposited and autocatalytic metallic coatings.
3.2 This standard outlines the process operation procedures and processing solutions required, that lead to satisfactory
electrodeposited metallic coatings (including undercoating) on surfaces of lead and lead-alloys.
4. Nature of Lead
4.1 The tensile strength of lead and lead alloys ranges from 15 to 35 MPa (2000 to 5000 psi), therefore, the measured adhesion
of electroplated coatings cannot be greater than these values.
4.2 Difficulties in applying high-quality electroplated coatings to lead are due to the following properties of lead:
4.2.1 The very active chemical nature of lead, leading to the formation of oxide films in air,
4.2.2 The fact that the lead surface will form films of insoluble lead salts with most acids used in pickling,
4.2.3 The ease with which lead diffuses in contact with nonferrous metals, and
4.2.4 The poor resistance to plastic deformation during polishing.
5. Process Precautions
5.1 The following process precautions should be observed:
5.1.1 Precleaning of raw castings is sometimes necessary to remove mold parting compounds, surface oxides, and residues from
recessed areas which are never reached by polishing-wheel or scratch-brush operations (Section 6).
5.1.2 In high-speed type cyanide electroplating solutions, the initial current density must be controlled and kept low enough so
that no gassing occurs to cause poor adhesion. This is revealed as groups of blisters in the high-current-density areas of the
electroplate.
This guide 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 Sept. 1, 2009Nov. 1, 2014. Published February 2010November 2014. Originally approved in 1957. Last previous edition approved in 20042009
as B319 – 91 (2004).(2009). DOI: 10.1520/B0319-91R09.10.1520/B0319-91R14.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
B319 − 91 (2014)
5.1.3 If a strike electroplate is used, it should be thick enough to prevent the next electroplating solution from attacking the basis
lead. A copper or nickel strike 2.5 μm thick should be used, but because there are so many variables involved, no specific
recommendations can be made.
5.1.4 Preplates should be of such thickness that complete alloying with the lead does not take place, an occurrence that causes
poor adhesion of subsequent deposits. This defect is indicated by blistering after prolonged storage or after an accelerated aging
test.
5.1.5 The lead compounds formed by the action of acids and alkalies most often used in electroplating are not water soluble.
Caution must be taken to remove or prevent the formation of these to eliminate subsequent adhesion failure. Acids that cannot be
used are sulfuric, hydrochloric, and hydrofluoric. (Acids that can be used are sulfamic and fluoboric.) Alkalies should not be high
in caustic content. Mild or buffered cleaners are preferred in order to minimize attack on the basis lead surface.
5.1.6 Engraving of electroplated finishes on lead cannot be performed on deposits over 5 μm thick as the deposit will tear away
from the lead at cross cuts. Engine turning by burnishing can be done on any thickness of deposits.
5.1.7 Polishing and coloring of the deposit must be performed at slow speeds, and with loose or cooled buffs to eliminate
overheating and flowing of basis metal.
6. Precleaning
6.1 Remove fins and parting lines by use of trimming dies or by scraping, filing, or grinding. Some machining may be done
at this point, such as drilling holes, or milling or cutting slots, groove, flats, or squared surfaces.
6.2 Clean in alkaline, emulsion type, or other standard cleaning material to remove surface materials (5.1.5).
6.3 After rinsing, transfer the parts into one of the following pickling solutions, the function of which is to remove surface
oxides, without significant attack on the lead surface.
6.3.1 An aqueous solution containing 250 mL of 48 mass %, fluoboric acid with or without 45 mL of 30 mass % hydrogen
peroxide diluted to 1 L. The addition of hydrogen peroxide will increase the aggressiveness of the pickling solution.
6.3.2 An aqueous solution containing 80 mL of glacial acetic acid and 45 mL of 30 mass % hydrogen peroxide diluted to 1 L.
6.3.3 An aqueous solution containing 100 g of sulfamic acid diluted to 1 L.
NOTE 1—These pickling solutions should be held in tanks having suitable nonmetallic linings.
6.4 After rinsing, an immersion in a water-displacing, film-forming material is advantageous. Sometimes a neutral soap, oil, or
synthetic emulsion film may be used according to the type of polishing compound to be used. These materials are removed in
subsequent operations.
7. Assembly of Parts
7.1 Precleaned parts then are ready for further assembly, such as soldering to other metals for ornamentation or mechanical
reasons.
8. Polishing or Buffing
8.1 After parting lines, fins, and gate marks are removed, greaseless compounds on loose cloth wheels are used for rough
smoothing followed by a soft leather, chamois, or sheepskin wheel operating at 15 to 25 surface m/s. These are used with white
lime compounds of various grease concentra
...