ASTM_B_841_-_18.pdf

Designation:B84118Standard Specification forElectrodeposited Coatings of Zinc Nickel Alloy Deposits1This standard is issued under the fixed designation B841;the number immediately following the designation indicates the year oforiginal adoption or,in the 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 electrode-posited zinc nickel alloy coatings on metals.1.2 The values stated in SI units are to be regarded as thestandard.1.3 The following precautionary statement pertains to thetest method portion only,Section 8,of this specification:Thisstandard does not purport to address all of the safety concerns,if any,associated with its use.It is the responsibility of the userof this standard to establish appropriate safety,health,andenvironmental practices and determine the applicability ofregulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2B117 Practice for Operating Salt Spray(Fog)ApparatusB183 Practice for Preparation of Low-Carbon Steel forElectroplatingB242 Guide for Preparation of High-Carbon Steel for Elec-troplatingB320 Practice for Preparation of Iron Castings for Electro-platingB322 Guide for Cleaning Metals Prior to ElectroplatingB374 Terminology Relating to ElectroplatingB487 Test Method for Measurement of Metal and OxideCoating Thickness by Microscopical Examination ofCross SectionB499 Test Method for Measurement of Coating Thicknessesby the Magnetic Method:Nonmagnetic Coatings onMagnetic Basis MetalsB504 Test Method for Measurement of Thickness of Metal-lic Coatings by the Coulometric MethodB507 Practice for Design of Articles to Be Electroplated onRacksB568 Test Method for Measurement of Coating Thicknessby X-Ray SpectrometryB571 Practice for Qualitative Adhesion Testing of MetallicCoatingsB602 Test Method for Attribute Sampling of Metallic andInorganic CoatingsB697 Guide for Selection of Sampling Plans for Inspectionof Electrodeposited Metallic and Inorganic CoatingsB762 Test Method of Variables Sampling of Metallic andInorganic CoatingsB849 Specification for Pre-Treatments of Iron or Steel forReducing Risk of Hydrogen EmbrittlementB850 Guide for Post-Coating Treatments of Steel for Reduc-ing the Risk of Hydrogen EmbrittlementD3951 Practice for Commercial Packaging3.Terminology3.1 DefinitionsMany items used in this specification aredefined in Terminology B374.3.2 Definitions of Terms Specific to This Standard:3.2.1 significant surface,nthat portion of a coated arti-cles surface where the coating is required to meet all therequirements of the coating specification for that article.Significant surfaces are usually those that are essential to theserviceability or function of the article,or that can be a sourceof corrosion products or tarnish films that interfere with thefunction or desirable appearance of the article.3.2.2 DiscussionSignificant surfaces are those surfacesthat are identified by the purchaser by,for example,indicatingthem on an engineering drawing of the product or marking asample item of the product.4.Classification4.1 There are two classes of zinc nickel coating defined asfollows:4.1.1 Class 1Deposits having a minimum of 5 and maxi-mum 12 mass%nickel,the balance being zinc.1This specification is under the jurisdiction of ASTM Committee B08 onMetallic and Inorganic Coatings and is the direct responsibility of SubcommitteeB08.06 on Soft Metals.Current edition approved July 1,2018.Published July 2018.Originally approvedin 1993.Last previous edition approved in 2018 as B841 99(2018).DOI:10.1520/B0841-18.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards 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 StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 4.1.2 Class 2Deposits having a minimum of 12 andmaximum 16 mass%nickel,the balance being zinc.4.2 There are five chromate conversion coating or passiva-tion types that are defined as follows:Conversion DesignationTypeDescriptionHexavalentChromiumNon-HexavalentChromiumType AColorless(BlueBright)ConversionAA