ASTM_B_650_-_95_2013.pdf

Designation:B65095(Reapproved 2013)Standard Specification forElectrodeposited Engineering Chromium Coatings onFerrous Substrates1This standard is issued under the fixed designation B650;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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 This specification covers the requirements for electrode-posited chromium coatings applied to ferrous alloys for engi-neering applications.1.2 Electrodeposited engineering chromium,which is some-times called“functional”or“hard”chromium,is usuallyapplied directly to the basis metal and is much thicker thandecorative chromium.Engineering chromium is used for thefollowing:1.2.1 To increase wear and abrasion resistance,1.2.2 To increase fretting resistance,1.2.3 To reduce static and kinetic friction,1.2.4 To reduce galling or seizing,or both,for various metalcombinations,1.2.5 To increase corrosion resistance,and1.2.6 To build up undersize or worn parts.1.3 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.2.Referenced Documents2.1 ASTM Standards:2B117 Practice for Operating Salt Spray(Fog)ApparatusB177 Guide for Engineering Chromium ElectroplatingB183 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-platingB374 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 PackagingE8 Test Methods for Tension Testing of Metallic MaterialsF1459 Test Method for Determination of the Susceptibilityof Metallic Materials to Hydrogen Gas Embrittlement(HGE)2.2 Other Standard:MIL-S-13165 Shot Peening of Metal Parts33.Terminology3.1 Definitions:1This specification is under the jurisdiction of ASTM Committee B08 onMetallic and Inorganic Coatings and is the direct responsibility of SubcommitteeB08.03 on Engineering Coatings.Current edition approved Dec.1,2013.Published December 2013.Originallyapproved in 1978.Last previous edition approved in 2008 as B650 95(2008).DOI:10.1520/B0650-95R13.2For 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.3Available from Standardization Documents Order Desk,Bldg.4 Section D,700Robbins Ave.,Philadelphia,PA 19111-5094,Attn:NPODS.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.1.1 significant surfacesall surfaces upon which a de-posit of controlled thickness is required.3.1.1.1 DiscussionWhen a controlled deposit is requiredin holes,corners,recesses,and similar areas,special racking,auxiliary anodes or shielding,or both,will be necessary.Withthe best practices there will be areas where a controlled depositis impossible.3.2 Definitions used in this specification are in accordancewith Terminology B374.4.Classification4.1 Electrodeposited chromium coatings in accordance withthis specification are classified by the thickness of the coatingas follows:Class No.Chromium Thickness,mTypical Application12.5 to 25reduce friction;anti-galling,lightwear resistance225 as specifiedbuildup to dimension specified forsalvage or as required for severewear resistance4.2 Unless otherwise specified by suitably marked drawingsor samples,only those surfaces that can be touched with a20-mm diameter ball shall be considered significant.In holes,corners,recesses,and other areas where a con