ASTM_A_917_-_08_2015.pdf

Designation:A91708(Reapproved 2015)Standard Specification forSteel Sheet,Coated by the Electrolytic Process forApplications Requiring Designation of the Coating Mass onEach Surface(General Requirements)1This standard is issued under the fixed designation A917;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 hot-rolled and cold-rolled steelsheet coated by the electrolytic process.Coatings can becomprised of pure metals or metal alloys.For specific coatings,refer to Specifications A879/A879M and A918.1.2 The product shall be coated on one or both surfaces withequal or differential coating masses on the two surfaces.Sheet-coated with equal coating masses on each surface hassimilar levels of corrosion protection on each surface.Often,however,a higher level of corrosion protection is required onone surface than is required on the other.In these situations,one surface shall be specified with a heavier coating mass thanthe other.Either surface,when specified to be painted,willprovide additional corrosion protection as compared to anunpainted surface.1.3 This coating process has essentially no effect on the basemetal mechanical properties,and use is permitted on any gradeof hot-rolled or cold-rolled steel sheet.The coated sheet isavailable as Commercial Steel(CS),Drawing Steel(DS),DeepDrawing Steel(DDS),Extra-Deep Drawing Steel(EDDS),StructuralSteel(SS)High-StrengthLow-AlloySteel(HSLAS),High-Strength Low-Alloy Steel with ImprovedFormability(HSLAS-F),Solution-Hardened Steel(SHS),orBake-Hardenable Steel(BHS).1.4 The values stated in SI units are to be regarded as thestandard.2.Referenced Documents2.1 ASTM Standards:2A90/A90M Test Method for Weight Mass of Coating onIron and Steel Articles with Zinc or Zinc-Alloy CoatingsA370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA754/A754M Test Method for Coating Weight(Mass)ofMetallic Coatings on Steel by X-Ray FluorescenceA879/A879M Specification for Steel Sheet,Zinc Coated bythe Electrolytic Process for Applications Requiring Des-ignation of the Coating Mass on Each SurfaceA902 Terminology Relating to Metallic Coated Steel Prod-uctsA918 Specification for Steel Sheet,Zinc-Nickel AlloyCoated by the Electrolytic Process for Applications Re-quiring Designation of the Coating Mass on Each SurfaceA1008/A1008M Specification for Steel,Sheet,Cold-Rolled,Carbon,Structural,High-Strength Low-Alloy,High-Strength Low-Alloy with Improved Formability,SolutionHardened,and Bake HardenableA1011/A1011M Specification for Steel,Sheet and Strip,Hot-Rolled,Carbon,Structural,High-Strength Low-Alloy,High-StrengthLow-AlloywithImprovedFormability,and Ultra-High StrengthB504 Test Method for Measurement of Thickness of Metal-lic Coatings by the Coulometric Method3.Terminology3.1 Definitions For definitions of terms and abbreviationsused in this specification,see Terminology A902.4.Ordering Information4.1 Ordering information for all products is shown in theindividual product specifications.5.Coating Designation(Mass and Type)5.1 The following seven-character format shall be used toidentify the coating mass required:5.1.1 First and Second Characters Minimum coatingmass of the surface with the less critical surface qualityrequirements;5.1.2 Third Character A letter,as designated in theappropriate product specification,to denote the kind of coating;G for pure zinc and N for zinc-nickel alloy;1This specification is under the jurisdiction of ASTM Committee A05 onMetallic-Coated Iron and Steel Products and is the direct responsibility ofSubcommittee A05.11 on Sheet Specifications.Current edition approved May 1,2015.Published May 2015.Originallyapproved in 1993.Last previous edition approved in 2008 as A917-08.DOI:10.1520/A0917-08R15.2For 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 States1 5.1.3 Fourth and Fifth Characters Minimum coatingmass of the surface with the more critical surface qualityrequirements;5.1.4 Sixth Character A letter,as designated in the appro-priate product specification,to denote the kind of coating;Gfor pure zinc and N for zinc-nickel alloy;5.1.5 Seventh CharacterEither E or U,designating anexposed or unexposed application,respectively.Example:60G20GESee Section:5.1.15.1.25.1.35.1.45.1.5NOTE1The terms“exposed”and“unexposed”describe the intendedapplication as either hidden or exposed to view and is an indicator of thedegree of freedom from surface imperfections that affect the cosmeticcharacteristics of the