1、Designation: A924/A924M 17aStandard Specification forGeneral Requirements for Steel Sheet, Metallic-Coated bythe Hot-Dip Process1This standard is issued under the fixed designation A924/A924M; the number immediately following the designation indicates the yearof original adoption or, in the case of
2、revision, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers the general requirements that,unless otherwise specified in the produ
3、ct specification, apply tosteel sheet in coils and cut lengths, metallic-coated on continu-ous lines by the hot-dip process. The product is intended forapplications requiring corrosion resistance. The product speci-fications contain requirements for specific strength levels, heatresistance, paintabi
4、lity, or formability, or a combinationthereof.1.2 Subject to individual product specification provisions,steel sheet is available as Commercial Steel (CS) Types A, B,and C, Forming Steel (FS), Drawing Steel (DS), Deep DrawingSteel (DDS), Extra Deep Drawing Steel (EDDS), High Tem-perature Steel (HTS)
5、, Structural Steel (SS), and High StrengthLow Alloy Steel (HSLAS). Steel sheet is produced with thefollowing metallic coatings. Specific information on each ofthe following is contained in the individual product specifica-tion:1.2.1 Zinc or zinc-iron alloy coated,1.2.2 Zinc-5 % aluminum alloy coated
6、,1.2.3 55 % aluminum-zinc alloy coated,1.2.4 Aluminum or aluminum-silicon alloy coated,1.2.5 Zinc-aluminum-magnesium alloy coated.1.3 Products covered by this general requirements specifi-cation are described in the following product standards: Speci-fications A463/A463M; A653/A653M; A755/A755M; A79
7、2/A792M; A875/A875M; A929/A929M; A1046/A1046M;A1057/A1057M; A1063/A1063M; and A1079.1.4 Metallic-coated steel sheet is produced to various coat-ing designations, as shown in the individual product specifica-tions. Except for differentially coated sheet, the coating isalways expressed as the total co
8、ating of both surfaces.1.5 In case of any conflict in requirements, the requirementsof the individual product specifications shall prevail over thoseof this general specification.1.6 The purchaser is permitted to specify additional require-ments that do not negate any of the provisions of this gener
9、alspecification or of the individual product specifications. Suchadditional requirements, the acceptance of which are subject tonegotiation with the supplier, shall be included in the orderinformation.1.7 For purposes of determining conformance with thisspecification and the various product specific
10、ations referencedin 1.3, values shall be rounded to the nearest unit in theright-hand place of figures used in expressing the limitingvalues (except to the nearest 5 MPa for SI strength values) inaccordance with the rounding method of Practice E29.1.8 Metallic-coated steel sheet covered by this spec
11、ificationis produced to thickness requirements expressed to 0.001 in.0.01 mm for both coils and cut lengths. The thickness is thetotal of the base steel and the coating.1.9 The text of this specification references notes andfootnotes that provide explanatory material. These notes andfootnotes (exclu
12、ding those in tables and figures) shall not beconsidered as requirements of the specification.1.10 The values stated in inch-pound units or SI units are tobe regarded separately as standard. Within the text, the SI unitsare shown in brackets. The values stated in each system are notexact equivalents
13、; therefore, each system must be used inde-pendently of the other.1.11 This specification and some of the applicable productspecifications are expressed in both inch-pound and SI units.However, unless the order specifies the applicable “M” speci-fication designation (SI units), the product shall be
14、furnished toinch-pound units.1.12 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 limitation
15、s prior to use.1.13 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 Tech
16、nicalBarriers to Trade (TBT) Committee.1This specification is under the jurisdiction of ASTM Committee A05 onMetallic-Coated Iron and Steel Products and is the direct responsibility of Subcom-mittee A05.11 on Sheet Specifications.Current edition approved Sept. 1, 2017. Published September 2017. Orig
17、inallyapproved in 1994. Last previous edition approved in 2017 as A924/A924M - 17.DOI: 10.1520/A0924_A0924M-17A.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis inter
18、national 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) Com
19、mittee.12. 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 ProductsA428/A428M Test Method for Weight Mass of Coating onAluminum-Coated Ir
20、on or Steel ArticlesA463/A463M Specification for Steel Sheet, Aluminum-Coated, by the Hot-Dip ProcessA653/A653M Specification for Steel Sheet, Zinc-Coated(Galvanized) or Zinc-Iron Alloy-Coated (Galvannealed)by the Hot-Dip ProcessA700 Guide for Packaging, Marking, and Loading Methodsfor Steel Product
21、s for ShipmentA751 Test Methods, Practices, and Terminology for Chemi-cal Analysis of Steel ProductsA754/A754M Test Method for Coating Weight (Mass) ofMetallic Coatings on Steel by X-Ray FluorescenceA755/A755M Specification for Steel Sheet, Metallic Coatedby the Hot-Dip Process and Prepainted by the
22、 Coil-Coating Process for Exterior Exposed Building ProductsA792/A792M Specification for Steel Sheet, 55 %Aluminum-Zinc Alloy-Coated by the Hot-Dip ProcessA875/A875M Specification for Steel Sheet, Zinc-5 % Alu-minum Alloy-Coated by the Hot-Dip ProcessA902 Terminology Relating to Metallic Coated Stee
23、l Prod-uctsA929/A929M Specification for Steel Sheet, Metallic-Coatedby the Hot-Dip Process for Corrugated Steel PipeA1030/A1030M Practice for Measuring Flatness Character-istics of Steel Sheet ProductsA1046/A1046M Specification for Steel Sheet, Zinc-Aluminum-Magnesium Alloy-Coated by the Hot-Dip Pro
24、-cessA1057/A1057M Specification for Steel, Structural Tubing,Cold Formed, Welded, Carbon, Zinc-Coated (Galvanized)by the Hot-Dip ProcessA1063/A1063M Specification for Steel Sheet, Twin-RollCast, Zinc-Coated (Galvanized) by the Hot-Dip ProcessA1073/A1073M Practice for Using Hand Micrometers toMeasure
25、 the Thickness of Uncoated Steel Sheet andNonmetallic and Metallic-Coated Steel SheetA1079 Specification for Steel Sheet, Complex Phase (CP),Dual Phase (DP) and Transformation Induced Plasticity(TRIP), Zinc-Coated (Galvanized) or Zinc-Iron Alloy-Coated (Galvannealed) by the Hot-Dip ProcessE29 Practi
26、ce for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE376 Practice for Measuring Coating Thickness byMagnetic-Field or Eddy-Current (Electromagnetic) Test-ing Methods2.2 Federal Standard:3Fed. Std. No. 123 Marking for Shipment (Civil Agencies)3. Terminology3.1 Defi
27、nitionsFor definitions of items used in thisspecification, refer to Terminology A902.4. Ordering Information4.1 Ordering information for all products are shown in theindividual product specifications.5. Materials and Manufacture5.1 Hot-dip metallic coatings are used to provide corrosionprotection to
28、 steel sheets. Hot-dip metallic coatings are avail-able in five different types, zinc and zinc-iron alloy, aluminum,55 % aluminum-zinc alloy, zinc-5 % aluminum alloy, andzinc-aluminum-magnesium alloy. Each coating type is avail-able in various coating weights which provide varying degreesof corrosio
29、n protection and the consumer should consult theindividual producers for applicability to the intended applica-tion and to obtain product information.5.2 Hot-dip metallic coated products may be subject tochanges in mechanical properties after coating. As suchchanges are functions of the chemistry an
30、d processing historyof the material, the consumer should consult the individualproducers for applicability to the intended application.6. Chemical Composition6.1 Base Steel:6.1.1 Chemical composition requirements of the base steelare shown in the individual product specifications.6.1.2 An analysis o
31、f each heat shall be made by themanufacturer to determine the percentage of carbon,manganese, phosphorus, sulfur, and any other elements speci-fied or restricted by the individual product specification.6.1.3 When desired, product analysis shall be made by thepurchaser on finished product. The produc
32、t analysis so deter-mined shall meet the tolerances shown in Table 1.6.1.3.1 Capped or rimmed steels are not technologicallysuited to product analysis due to the nonuniform character oftheir chemical composition, and therefore, the tolerances inTable 1 do not apply. Product analysis is appropriate o
33、n thesesteels only when misapplication is apparent.6.1.3.2 Product analysis for phosphorus or sulfur is nottechnologically appropriate because of segregation of theseelements in non-killed steels. Product analysis is appropriateonly when misapplication is apparent.6.1.3.3 Samples for product analysi
34、s shall be drillingsthrough areas stripped free of coating. At least three piecesshall be selected, but if the product of more than one mill liftor coil is involved, at least six pieces shall be selected.6.1.3.4 When supplying High-Strength Low-Alloy Steel(HSLA), some producers use one or more micro
35、alloyingelements as strengthening agents or use alloy additions to effect2For 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 A
36、STM website.3Available from Yale University Library, Standardization Documents OrderDesk, Bldg. 4 Section D, 700 Robbins Ave., Philadelphia, PA 191115094, Attn:NPODS.A924/A924M 17a2inclusion control, or both. The producer shall be consulted forthe specific chemical composition applied. If any alloyi
37、ngaddition is known to be of concern to the user, the producershall be notified of this concern.6.1.4 Method of AnalysisThe determination of chemicalcomposition is permitted to be made by any test method,except in case of dispute, where the referee test methods listedin the section on test methods o
38、f Test Methods A751 shall beused.6.2 Coating:6.2.1 Coating AnalysisThe nominal composition of thecoating is described in the individual product specification.6.2.2 Method of AnalysisThe determination of chemicalcomposition shall be made in accordance with acceptablechemical, spectrochemical, or othe
39、r test methods.7. Tests for Mechanical Properties7.1 Test specimens shall be prepared from finished metallic-coated product.7.2 Mechanical Properties-Base MetalWhen base metalmechanical properties are specified, tests shall be conducted inaccordance with Test Methods A370. Requirements for allmechan
40、ical properties are included in the individual productspecifications.7.2.1 Tension TestsSpecimens for base-metal tension testsshall be taken longitudinally, approximately midway betweenthe center and edge of the product as rolled, and shall conformto the requirements for the sheet-type test specimen
41、 in thefigure for rectangular tension test specimens of Test MethodsA370.7.2.1.1 The determination of the yield strength and tensilestrength values shall be based on the as-produced base-metalthickness that shall be obtained by one of the followingmethods. Unless specified in the order, the producer
42、 shalldetermine the method to be used; however, in the event of adispute the method in 7.2.1.2 shall be used.7.2.1.2 The base metal thickness shall be determined bystripping the coating from the ends of the specimen contactingthe grips of the tension testing machine. The thickness mea-surement shall
43、 be made before testing on an end of thespecimen that has been stripped free of coating.7.2.1.3 The base metal thickness shall be determined bysubtracting the coating thickness from the measured thicknessof the tension test specimen. The coating thickness shall becalculated from the coating weight m
44、ass test.7.2.1.4 Two tension tests shall be made from each heat andordered thickness for all thickness ranges of 0.020 in.0.51 mm for cold rolled substrate and thickness ranges of0.050 in. 1.27 mm for hot rolled substrate. If testing isperformed on a per coil basis, only one tension test shall bereq
45、uired for each master coil.(1) Example: For cold rolled substrate, if ordered thicknessis 0.046 in. 1.17 mm, there must be two test results within anyrange of 0.020 in. 0.51 mm, including but not limited to thefollowing:0.026 in. through 0.046 in. 0.66 mm through 1.17 mm0.046 in. through 0.066 in. 1
46、.17 mm through 1.68 mm0.030 in. through 0.050 in. 0.76 mm through 1.27 mm8. Tests for Coating Properties8.1 Coating Weight Mass:8.1.1 Coating weight mass shall conform to the require-ments prescribed in the individual product specifications (see1.3).8.1.2 The coating weight mass is ordered as total
47、bothsides requirements, or if requested on those product specifica-tions permitting it, to single side/single spot coating massrequirements.8.1.3 Total both sides requirements8.1.3.1 The coating weight mass of equally coated productis the total amount on both sides of the sheet, expressed inounces p
48、er square foot grams per square metre of sheet.8.1.3.2 For differentially coated product, the coating weightmass on each surface is nominally one half of the statedcoating designation.8.1.4 Single side/single spot requirements8.1.4.1 The coating mass for each surface shall be specifiedseparately, fo
49、r example, 60G60G, and each single spot testshall meet the specified requirements for the coating designa-tion.8.2 Coating Weight Mass TestsOne of the following testmethods shall be used:8.3 Weigh-Strip-Weigh Method:8.3.1 The weigh-strip-weigh method, described in TestMethods A90/A90M and A428/A428M, is a destructive testthat determines coating weight mass by measuring thedifference in weight mass between a coated and a stripped(uncoated) sample. If one surface is protected suitably duringthe initial stripping, coating weight mass can
