1、Designation: A 917 08Standard 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 A 917; the number immediately following the designation i
2、ndicates 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers hot-rolled
3、and cold-rolled steelsheet coated by the electrolytic process. Coatings can becomprised of pure metals or metal alloys. For specific coatings,refer to Specifications A 879/A 879M and A 918.1.2 The product shall be coated on one or both surfaces withequal or differential coating masses on the two sur
4、faces.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 coa
5、ting 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-roll
6、ed steel sheet. The coated sheet isavailable as Commercial Steel (CS), Drawing Steel (DS), DeepDrawing Steel (DDS), Extra-Deep Drawing Steel (EDDS),Structural Steel (SS) High-Strength Low-Alloy Steel(HSLAS), High-Strength Low-Alloy Steel with ImprovedFormability (HSLAS-F), Solution-Hardened Steel (S
7、HS), orBake-Hardenable Steel (BHS).1.4 The values stated in SI units are to be regarded as thestandard.2. Referenced Documents2.1 ASTM Standards:2A 90/A 90M Test Method for Weight Mass of Coating onIron and Steel Articles with Zinc or Zinc-Alloy CoatingsA 370 Test Methods and Definitions for Mechani
8、cal Testingof Steel ProductsA 754/A 754M Test Method for Coating Weight (Mass) ofMetallic Coatings on Steel by X-Ray FluorescenceA 879/A 879M Specification for Steel Sheet, Zinc Coatedby the Electrolytic Process for Applications RequiringDesignation of the Coating Mass on Each SurfaceA 902 Terminolo
9、gy Relating to Metallic Coated Steel Prod-uctsA 918 Specification for Steel Sheet, Zinc-Nickel AlloyCoated by the Electrolytic Process for Applications Re-quiring Designation of the Coating Mass on Each SurfaceA 1008/A 1008M Specification for Steel, Sheet, Cold-Rolled, Carbon, Structural, High-Stren
10、gth Low-Alloy,High-Strength Low-Alloy with Improved Formability, So-lution Hardened, and Bake HardenableA 1011/A 1011M Specification for Steel, Sheet and Strip,Hot-Rolled, Carbon, Structural, High-Strength Low-Alloy,High-Strength Low-Alloy with Improved Formability, andUltra-High StrengthB 504 Test
11、Method for Measurement of Thickness of Me-tallic Coatings by the Coulometric Method1This 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
12、 1, 2008. Published May 2008. Originallyapproved in 1993. Last previous edition approved in 2006 as A 917 - 06a.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
13、standards Document Summary page onthe ASTM website.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3. Terminology3.1 DefinitionsFor definitions of terms and abbreviati
14、onsused in this specification, see Terminology A 902.4. 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
15、.1 First and Second CharactersMinimum coatingmass of the surface with the less critical surface qualityrequirements;5.1.2 Third CharacterA letter, as designated in the appro-priate product specification, to denote the kind of coating; Gfor pure zinc and N for zinc-nickel alloy;5.1.3 Fourth and Fifth
16、 CharactersMinimum coatingmass of the surface with the more critical surface qualityrequirements;5.1.4 Sixth CharacterA 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, des
17、ignating anexposed or unexposed application, respectively.Example: 60 G 20 G ESee Section: 5.1.1 5.1.2 5.1.3 5.1.4 5.1.5NOTE 1The terms “exposed” and “unexposed” describe the intendedapplication as either hidden or exposed to view and is an indicator of thedegree of freedom from surface imperfection
18、s that affect the cosmeticcharacteristics of the coated surface.6. Chemical Requirements6.1 The heat analysis of the steel shall conform to therequirements of the specification for the steel ordered or asspecified by negotiations.7. Base Metal Requirements7.1 The steel shall conform to all of the re
19、quirements of theappropriate specification listed as follows for the steel ordered.Where reference is made to a combined standard (such asSpecification A 1011/A 1011M), conformance shall be to themetric portion, using SI units of measurement as standard.7.1.1 Hot Rolled:7.1.1.1 Commercial Steel (CS)
20、, Drawing Steel (DS), Struc-tural Steel (SS), High-Strength Low-Alloy Steel (HSLAS), andHigh-Strength Low-Alloy Steel with Improved Formability(HSLAS-F)Specification A 1011/A 1011M.7.1.2 Cold Rolled:7.1.2.1 Commercial Steel (CS), Drawing Steel (DS), DeepDrawing Steel (DDS), Extra-Deep Drawing Steel
21、(EDDS),Structural Steel (SS), High-Strength Low-Alloy Steel (HSLAS),High-Strength Low-Alloy Steel with Improved Formability(HSLAS-F), Solution-Hardened Steel (SHS), and Bake-Hardenable Steel (BHS)Specification A 1008/A 1008M.7.2 Base Metal Specimens:7.2.1 Test specimens shall be prepared from finish
22、ed mate-rial and tested in accordance with Test Methods and DefinitionsA 370.7.2.2 In determining the base metal mechanical properties,one of the following methods shall be used. Unless specified inthe order, the producer shall determine the method to be used;however, in the event of a dispute the m
23、ethod in 7.2.2.1 shallbe used.7.2.2.1 The base metal thickness shall be measured afterstripping the coating from the ends of the specimen contactingthe grips of the tension testing machine before testing.7.2.2.2 The base metal thickness shall be determined bysubtracting the coating thickness from th
24、e measured thicknessof the tension test specimen. The coating thickness shall becalculated from the coating mass test.7.2.3 When the percent elongation in the tension test is lessthan the specified minimum and any part of the fracture isoutside the middle half of the gage length as scribed before th
25、etest, the test shall be discarded and a retest shall be permitted.7.3 Retests for Base Metal Mechanical PropertiesIf onetest fails for base metal mechanical requirements, retestingshall conform to the provisions of the applicable base metalspecification.8. Coating Mass Requirements8.1 Coating Mass:
26、8.1.1 Coating mass shall conform to the requirements pre-scribed in the individual coating specification.8.1.2 The mass of the coating is the single spot value oneach surface of the sheet expressed in grams per square metre.8.2 Coating Mass Tests:8.2.1 Test Method A 90/A 90MThe weigh-strip-weighmeth
27、od is a destructive test that determines coating mass bymeasuring the difference in weight between a coated and astripped (uncoated) sample. If one surface is protected suitablyduring the initial stripping, coating mass can be determined foreach surface independently. Conversion of the coating tocoa
28、ting thickness is only possible if the density of the coatingis known precisely.8.2.2 Test Method A 754/A 754MMeasurement by X-rayfluorescence is a nondestructive test that determines coatingmass by converting X-ray fluorescence measurements to coat-ing mass values. This test method is readily adapt
29、able to thecontinuous monitoring of coating mass during the electroplat-ing process. Thus, modern electroplating facilities are fre-quently equipped with X-ray fluorescence gages that providefeedback to control the coating mass. These devices are used asa basis for determining suitability for shipme
30、nt provided thatthey have been calibrated properly.8.2.3 Test Method B 504Measurement of the coating massby the coulometric method is a destructive test that determinescoating mass or thickness, or both, electrochemically. This testmethod is rapid and versatile for lighter coating mass applica-tions
31、.8.2.4 The referee method to be used shall be as agreed uponbetween the producer and the consumer. In the absence of suchagreement, Test Method A 90/A 90M, the weigh-strip-weighmethod, shall be used as the referee method.8.3 Sampling for Coated Mass Test:A9170828.3.1 One test specimen shall be taken
32、 from the lift of cutlengths or coils such that no portion of the specimen is closerthan 25 mm to the edge of the as-received sheet.8.3.2 The coating mass of this specimen shall conform toboth the minimum and maximum values shown in the appli-cable coating specification for the coating mass specifie
33、d. Ifeither of these values is not met, the material represented shallbe subject to retest in accordance with the procedures given in9.4.8.4 Retest for Coating Mass Values:8.4.1 When it is desired to retest to determine compliance tothe coating mass values, two test specimens shall be selected atran
34、dom from the same lift of cut lengths or coil, such that noportion of either sample is closer than 25 mm from theas-received edges.8.4.2 When tested, each of the two retest specimens shallconform to both the minimum and maximum values shown inthe specification for the coating mass specified.9. Coati
35、ng Bend Test Requirements9.1 For all steel designations other than structural steel,high-strength low-alloy steel and high-strength low-alloy steelwith improved formability, the coated sheet shall be capable ofbeing bent flat through 180 in any direction without flaking ofthe coating on the outside
36、of bend only.9.2 Coated cold-rolled structural steel sheet in Grades 25,30, 33 Types 1 and 2, and 40 Types 1 and 2, coated cold-rolledsolution-hardened steel sheet in Grades 26, 31, 35, 41, and 44,coated cold-rolled bake-hardenable steel sheet in Grades 26,31, 35, 41, and 44, and coated hot-rolled s
37、tructural steel sheetin Grades 30, 33, 36 Types 1 and 2, 40, 45, 50, and 55 shall becapable of being bent through 180 in any direction withoutflaking of the coating on the outside of the bend only. Thecoating bend test inside diameter shall have a relationship tothe thickness of the specimen as pres
38、cribed in Table 1. There isno coating bend test applicable to cold-rolled structural steelGrade 80.9.3 Coated cold-rolled and hot-rolled high-strength low-alloy steel, and high-strength low-alloy steel with improvedformability sheet shall be capable of being bent through 180in nay direction without
39、flaking of the coating on the outside ofthe bend only. The coating bend test inside diameter shall havea relationship to the thickness of the specimen as prescribed inTable 2.9.4 Flaking of the coating within 6 mm of the edge of thebend specimen shall not be cause for rejection.9.5 Coating bend test
40、 specimens shall be cut 50 to 100 mmwide. The specimen shall be cut not less than 50 mm from theedge of the test sheet.9.6 Electrolytic coatings are usually tightly adherent, evenwhen used for difficult forming operations. However, powder-ing is possible if the material is severely formed or coinedd
41、uring forming.9.7 Retests for Coating Bend Tests:9.7.1 If the specimen fails the coating bend test, two retestsshall be taken on random samples from the same lot of anyspecific item.9.7.2 Both retests must conform to the requirements of thisspecification.10. Certification10.1 When specified in the p
42、urchase order or contract, thepurchaser shall be furnished with certification that samplesrepresenting each lot have been either tested or inspected asdirected in this specification and the requirements have beenmet. When specified in the purchase order or contract, a reportof the test results shall
43、 be furnished. The report shall includethe purchase order number, theASTM designation number, andthe heat or lot number correlating the test results with thematerial represented.11. Keywords11.1 coatings, metallic; coatings, zinc; electrodepositedcoatings; steel products; steel sheet; steel sheet-zi
44、nc coated;zinc coated (electrolytic process); zinc-coated iron/steel ar-ticles; zinc coatingsTABLE 1 Coating Bend Test for Structural SteelRatio of the Bend Diameter to the Thickness of the SpecimenACold-Rolled Sheet, GradeB25 30 33 Types 1 and 2 40 Types 1 and 2112 2212 3Hot-Rolled Sheet, Grade30 3
45、3 36 Types 1 and 2 40 45 50 551112 112 2212 33AThese ratios are applicable for all coating designations.BGrade 80 is not subject to any bend test requirement; therefore, there is nocoating bend requirement for this grade.TABLE 2 Coating Bend Test for High-Strength Low-Alloy Steeland High-Strength Lo
46、w-Alloy Steel with Improved FormabilityRatio of the Bend Test Diameter to the thickness of the SpecimenAHigh-Strength Low-Alloy Steel Sheet, Grade, Classes 1 and 245 50 55 60 65 70112 22212 212 3High-Strength Low-Alloy Steel with Improved Formability Sheet, Grade50 60 70 802212 33ARatios are applica
47、ble for all coating designations.A917083SUMMARY OF CHANGESCommitteeA05 has identified the location of selected changes to this standard since the last issue,A 917 - 06a,that may impact the use of this standard. (May 1, 2008)(1) Revised 7.2.2.(2) Added 7.2.2.1 and 7.2.2.2.ASTM International takes no
48、position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsi
49、bility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the
