1、Designation: B604 91 (Reapproved 2015)Standard Specification forDecorative Electroplated Coatings of Copper Plus NickelPlus Chromium on Plastics1This standard is issued under the fixed designation B604; the number immediately following the designation indicates the year oforiginal adoption or, in th
2、e case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers the requirements for severalgrades and types of electrodepos
3、ited copper plus nickel pluschromium coatings on plateable plastic substrates whereappearance, durability and resistance to thermal cycling areimportant to service performance. Five grades of coatings areprovided to correlate with the service conditions under whicheach is expected to provide satisfa
4、ctory performance.1.2 This specification covers the requirements for coatingsapplied subsequent to the application of metal film by auto-catalytic deposition or subsequent to the application of anystrike coatings after autocatalytic deposition.1.3 The following caveat pertains only to the test metho
5、dportions of Section 6, Annex A1, and Appendix X2, AppendixX3, and Appendix X4 of this specification. This standard doesnot purport to address all of the safety concerns, if any,associated with its use. It is the responsibility of the user of thisstandard to establish appropriate safety and health p
6、racticesand determine the applicability of regulatory limitations priorto use.2. Referenced Documents2.1 ASTM Standards:2B368 Test Method for Copper-Accelerated Acetic Acid-SaltSpray (Fog) Testing (CASS Test)B487 Test Method for Measurement of Metal and OxideCoating Thickness by Microscopical Examin
7、ation ofCross SectionB489 Practice for Bend Test for Ductility of Electrodepos-ited and Autocatalytically Deposited Metal Coatings onMetalsB504 Test Method for Measurement of Thickness of Metal-lic Coatings by the Coulometric MethodB530 Test Method for Measurement of Coating Thicknessesby the Magnet
8、ic Method: Electrodeposited Nickel Coat-ings on Magnetic and Nonmagnetic SubstratesB532 Specification for Appearance of Electroplated PlasticSurfacesB533 Test Method for Peel Strength of Metal ElectroplatedPlasticsB556 Guide for Measurement of Thin Chromium Coatingsby Spot TestB567 Test Method for M
9、easurement of Coating Thicknessby the Beta Backscatter MethodB568 Test Method for Measurement of Coating Thicknessby X-Ray SpectrometryB602 Test Method for Attribute Sampling of Metallic andInorganic CoatingsB659 Guide for Measuring Thickness of Metallic and Inor-ganic CoatingsB727 Practice for Prep
10、aration of Plastics Materials for Elec-troplatingB764 Test Method for Simultaneous Thickness and Elec-trode Potential Determination of Individual Layers inMultilayer Nickel Deposit (STEP Test)D1193 Specification for Reagent WaterE50 Practices for Apparatus, Reagents, and Safety Consid-erations for C
11、hemical Analysis of Metals, Ores, andRelated Materials3. Terminology3.1 Definitions:3.1.1 significant surfacesthose surfaces normally visible(directly or by reflection) that are essential to the appearance orserviceability of the article when assembled in normal positionor that can be the source of
12、corrosion products that defacevisible surfaces on the assembled article.4. Classification4.1 Five grades of coatings designated by service conditionnumbers and several types of coatings defined by classificationnumbers are covered by this specification.4.2 Service Condition Number:4.2.1 The service
13、condition number indicates the severity ofexposure for which the grade of coating is intended, in1This specification is under the jurisdiction of ASTM Committee B08 onMetallic and Inorganic Coatings and is the direct responsibility of SubcommitteeB08.05 on Decorative Coatings.Current edition approve
14、d March 1, 2015. Published April 2015. Originallyapproved in 1975. Last previous edition approved in 2008 as B604 91 (2008).DOI: 10.1520/B0604-91R15.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStanda
15、rds volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1accordance with the following scale:SC5extended very severeSC4very severeSC3severeSC2moderateSC1mi
16、ld4.2.2 Service condition numbers are further defined inAppendix X1 where they are related to the severity of exposureencountered by electroplated articles.4.3 Coating Classification Number The coating classifi-cation number is a means of specifying the types and thick-nesses of coatings appropriate
17、 for each grade and is comprisedof the following:4.3.1 The symbol for the substrate (PL) indicating it isplateable plastic, followed by a slash mark,4.3.2 The chemical symbol for copper (Cu),4.3.3 Anumber giving the minimum thickness of the coppercoating in micrometres,4.3.4 A lower-case letter desi
18、gnating the type of copperelectrodeposit (see 4.4 and 6.3.1),4.3.5 The chemical symbol for nickel (Ni),4.3.6 A number giving the minimum thickness of the nickelin micrometres,4.3.7 A lower-case letter designating the type of nickelelectrodeposit (see 4.4 and 6.3.2),4.3.8 The chemical symbol for chro
19、mium (Cr), and4.3.9 A lower-case letter or letters designating the type ofchromium (see 4.4 and 6.3.3).4.4 Symbols for Expressing ClassificationThe followinglower-case letters shall be used in coating classification num-bers to describe the types of coatings:a ductile copper deposited from acid-type
20、 bathsb single-layer nickel deposited in the fully-bright conditiond double- or triple-layer nickel coatingsr regular (that is, conventional) chromiummc microcracked chromiummp microporous chromium4.5 Example of Complete Classification NumberAcoatingon plastic comprising 15 m minimum ductile acid co
21、pper plus15 m minimum double-layer nickel plus 0.25 m minimummicroporous chromium has the classification number: PL/Cu15a Ni15d Cr mp.5. Ordering Information5.1 When ordering articles to be electroplated in accordancewith this standard, the purchaser shall state the following:5.1.1 ASTM designation
22、number.5.1.2 Either the classification number of the specific coatingrequired (see 4.3) or the substrate material and the servicecondition number denoting the severity of the conditions it isrequired to withstand (see 4.2). If the service condition numberis quoted and not the classification number,
23、the manufacturer isfree to supply any of the types of coatings designated by theclassification number corresponding to the service conditionnumber, as given in Table 1.3On request, the manufacturershall inform the purchaser of the classification number of thecoating applied.5.1.3 The appearance requ
24、ired, for example, bright, dull, orsatin. Alternatively, samples showing the required finish orrange of finish shall be supplied or approved by the purchaser.5.1.4 The significant surfaces, to be indicated on drawingsof the parts, or by the provision of suitably marked specimens(see 3.1).5.1.5 The p
25、ositions on significant surfaces for rack orcontact marks, where such marks are unavoidable (see 6.1.1).5.1.6 The extent to which defects shall be tolerated onnonsignificant surfaces.5.1.7 The ductility if other than the standard value (see 6.4).5.1.8 The extent of tolerable surface deterioration af
26、tercorrosion testing (see 6.6.3).5.1.9 Sampling methods and acceptance levels (See Section7).5.1.10 Whether thermal cycle and corrosion testing shall beconducted individually on separate specimens as described in6.6 and 6.7, or sequentially using the same specimens asdescribed in 6.8, and whether th
27、e specimens shall be un-mounted or mounted in a manner simulating assembly whenthese tests are conducted.5.2 The minimum values of the electrochemical potentialdifferences between individual nickel layers as measured inaccordance with Test Method B764 within the limits given in6.10.6. Product Requir
28、ements6.1 Visual Defects:6.1.1 The significant surfaces of the electroplated articlesshall be free of visible defects, such as blisters, pits, roughness,cracks, and uncoated areas, and shall not be stained ordiscolored. On articles where a visible contact mark isunavoidable, its position shall be sp
29、ecified by the purchaser.The electroplated article shall be free of damage and clean.6.1.2 Defects in the surface of the molded plastic, such ascold shots, ejection marks, flash, gate marks, parting lines,splay and others, may adversely affect the appearance andperformance of coatings applied theret
30、o despite the observance3“Performance of Decorative Electrodeposited Copper-Nickel-Chromium Coat-ings on Plastics” is a final report on programs conducted by ASTM and ASEP toevaluate the coating classification numbers. A copy of the report has been filed atASTM Headquarters as RR B-8-1003.TABLE 1 Co
31、pper Plus Nickel Plus Chromium Coatings onPlasticAServiceConditionNumberClassification NumberEquivalent Nickel Thicknessm mils (approx.)SC 5 PL/Cu15a Ni30d Cr mcPL/Cu15a Ni30d Cr mp30301.21.2SC 4 PL/Cu15a Ni30d Cr rPL/Cu15a Ni25d Cr mcPL/Cu15a Ni25d Cr mp3025251.21.01.0SC 3 PL/Cu15a Ni25d Cr rPL/Cu1
32、5a Ni20d Cr mcPL/Cu15a Ni20d Cr mp2520201.00.80.8SC 2 PL/Cu15a Ni15b Cr rPL/Cu15a Ni10b Cr mcPL/Cu15a Ni10b Cr mp1510100.60.40.4SC 1 PL/Cu15a Ni7b Cr r 7 0.3AThe minimum copper thickness may be greater in some applications to meetthermal cycling and other requirements.B604 91 (2015)2of the best elec
33、troplating practice.Accordingly, the electroplat-ers responsibility for defects in the coating resulting from theplastic-molding operation shall be waived (Note 1).NOTE 1To minimize problems of this type, the specifications coveringthe items to be electroplated should contain appropriate limitations
34、 on theextent of surface defects. Practice B532 distinguishes between defects thatarise primarily in molding and those that arise in electroplating operations.6.2 PretreatmentsProper preparatory procedures are es-sential for satisfactory performance of electrodeposited coat-ings on plastics. Procedu
35、res described in Practice B727 may befollowed. In the case of patented processes, the instructionsprovided by the suppliers of those processes shall be followed.6.3 Process and Coating RequirementsFollowing prepa-ratory operations, plastic articles are placed in electroplatingsolutions as required t
36、o produce the composite coating de-scribed by the specific coating classification number or bycoating one of the specified classification numbers listed inTable 1 appropriate for the specified service condition number.6.3.1 Type of CopperDuctile copper shall be depositedfrom acid-type baths containi
37、ng organic additives that promoteleveling by the copper deposit.6.3.2 Type of NickelFor double- or triple-layer nickelcoatings, the bottom layer shall contain less than 0.005 mass %sulfur (Note 2). The top layer shall contain greater than 0.04mass % sulfur (Note 3), and its thickness shall be not le
38、ss than10 % of the total nickel thickness. In double-layer coatings, thethickness of the bottom layer shall be not less than 60 % of thetotal nickel thickness. In triple-layer coatings, the bottom layershall be not less than 50 % nor more than 70 %. If there arethree layers, the intermediate layer s
39、hall contain not less than0.15 mass % sulfur and shall not exceed 10 % of the totalnickel thickness. These requirements for multilayer nickelcoatings are summarized in Table 2.6.3.3 Thickness of Chromium DepositThe minimum per-missible thickness of the chromium deposit shall be 0.25 m onsignificant
40、surfaces. The thickness of chromium is designatedby the same symbol as the type instead of by numerals as in thecase of copper and nickel (see 4.4).NOTE 2The sulfur content is specified in order to indicate which typeof nickel electroplating solution must be used.Although no simple methodis yet avai
41、lable for determining the sulfur content of a nickel deposit on acoated article, chemical determinations are possible using speciallyprepared test specimens. See Appendix X2 for the determination of sulfurin electrodeposited nickel.NOTE 3It will usually be possible to identify the type of nickel bym
42、icroscopical examination of the polished and etched section of an articleprepared in accordance with Test Method B487. The thickness of theindividual nickel layers in double-layer and triple-layer coatings, as wellas the electrochemical relationships between the individual layers can bemeasured by t
43、he STEP test in accordance with Test Method B764.6.4 DuctilityThe minimum value of the ductility shall be8 % for copper and for nickel when tested by the method givenin Appendix X3. Greater ductility may be requested but shallbe subject to agreement between the purchaser and the manu-facturer.6.5 Co
44、ating Thickness:6.5.1 The minimum coating thickness shall be as designatedby the coating classification number.6.5.2 It is recognized that requirements may exist for thickercoatings than are covered by this specification.6.5.3 The thickness of a coating and its various layers shallbe measured at poi
45、nts on the significant surfaces (see 4.2 andNote 4.)NOTE 4When significant surfaces are involved on which the specifiedthickness of deposit cannot readily be controlled, such as threads, holes,deep recesses, bases of angles, and similar areas, the purchaser and themanufacturer should recognize the n
46、ecessity for either thicker deposits onthe more accessible surfaces or for special racking. Special racks mayinvolve the use of conforming, auxiliary, or bipolar electrodes, ornonconducting shields.6.5.3.1 The coulometric method described in Test MethodB504 may be used to measure thickness of the ch
47、romium, thetotal thickness of the nickel, and the thickness of the copper.The STEP test, Test Method B764, which is similar to thecoulometric method, may be used to determine the thicknessesof individual layers of nickel in a multilayer coating.6.5.3.2 The microscopical method described in Test Meth
48、odB487 may be used to measure the thickness of each nickellayer and of the copper layer.6.5.3.3 The beta backscatter method described in TestMethod B567 may be used when the total thickness of acopper/nickel/chromium composite coating is to be measured,without any indication of the thickness of each
49、 individual layer.6.5.3.4 Other methods may be used if it can be demon-strated that the uncertainty of the measurement is less than10 %, or less than that of any applicable method mentioned in6.4.3. Other methods are outlined in Test Methods B530 andB568 and Guides B556 and B659.6.6 Corrosion Testing:6.6.1 Coated articles shall be subjected to the corrosion testfor a period of time that is appropriate for the particular servicecondition number (or for the service condition number corre-sponding to a specified classification number) as shown inTab