ASTM_B_809_-_95_2013.pdf

Designation:B80995(Reapproved 2013)Standard Test Method forPorosity in Metallic Coatings by Humid Sulfur Vapor(“Flowers-of-Sulfur”)1This standard is issued under the fixed designation B809;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 standard covers equipment and test methods fordetermining the porosity of metallic coatings,where the porespenetrate down to a silver,copper,or copper-alloy substrate.1.2 This test method is suitable for coatings consisting ofsingle or combined layers of any coating that does notsignificantly tarnish in a reduced sulfur atmosphere,such asgold,nickel,tin,tin-lead,and palladium,or their alloys.1.3 This test method is designed to determine whether theporosity level is less than or greater than some value which byexperience is considered by the user to be acceptable for theintended application.1.4 Recent reviews of porosity testing and testing methodscan be found in the literature.2,3Guide B765 is suitable toassist in the selection of porosity tests for electrodeposits andrelated metallic coatings.Other porosity test standards are TestMethods B735,B741,B798,and B799.1.5 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.6 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility 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.For specific hazardsstatements,see Section 8.2.Referenced Documents2.1 ASTM Standards:4B374 Terminology Relating to ElectroplatingB542 Terminology Relating to Electrical Contacts and TheirUseB735 Test Method for Porosity in Gold Coatings on MetalSubstrates by Nitric Acid VaporB741 Test Method for Porosity In Gold Coatings On MetalSubstrates By Paper Electrography(Withdrawn 2005)5B765 Guide for Selection of Porosity and Gross Defect Testsfor Electrodeposits and Related Metallic CoatingsB798 Test Method for Porosity in Gold or Palladium Coat-ings on Metal Substrates by Gel-Bulk ElectrographyB799 Test Method for Porosity in Gold and PalladiumCoatings by Sulfurous Acid/Sulfur-Dioxide Vapor3.Terminology3.1 DefinitionsMany terms used in this test method aredefined in Terminologies B374 and B542.3.2 Definitions of Terms Specific to This Standard:3.2.1 corrosion productsreaction products of the basismetal or underplate,that protrude from,or are otherwiseattached to,the coating surface after the test exposure.3.2.2 measurement areain this test method,that portion orportions of the surface that is examined for the presence ofporosity.The measurement area shall be indicated on thedrawings of the parts,or by the provision of suitably markedsamples.3.2.3 metallic coatingsin this test method,includeplatings,claddings,or other metallic coatings applied to thesubstrate.The coating can comprise a single metallic layer ora combination of metallic layers.1This test method is under the jurisdiction ofASTM Committee B08 on Metallicand Inorganic Coatings and is the direct responsibility of Subcommittee B08.10 onTest Methods.Current edition approved Dec.1,2013.Published December 2013.Originallyapproved in 1990.Last previous edition approved in 2008 as B809 95(2008).DOI:10.1520/B0809-95R13.2Clarke,M.,“Porosity and Porosity Tests,”Properties of Electrodeposits,Sard,Leidheiser,and Ogburn,eds.,The Electrochemical Society,1975,p.122.3Krumbein,S.J.,“Porosity Testing of Contact Platings,”Transactions of theConnectors and Interconnection Technology Symposium,Philadelphia,PA,October1987,p.47.4For 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.5The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.2.4 porositythe presence of any discontinuity,crack,orhole in the coating that exposes a different underlying metal(see Guide B765).3.2.5 significant surface of a coated part,is that portion(or portions)of the coating surface that is essential to theserviceability or function of the part,or which can be thesource of corrosion products or tarnish films that interfere withthe function of the part.For many plated products,the criticalsurface is identical to the measurement area.3.2.6 tarnishreaction products of copper or silver withoxygen or reduced sulfur(that is,hydrogen sulfide(H2S)andelemental sulfur vapor,but not sulfur dioxide(SO2)or othersulfur oxides).They consist of thin films or