1、Designation: A 308/A 308M 06Standard Specification forSteel Sheet, Terne (Lead-Tin Alloy) Coated by the Hot-DipProcess1This standard is issued under the fixed designationA 308/A 308M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision,
2、 the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This specification cov
3、ers sheet steel in coils and cutlengths coated with lead-tin alloy (terne metal, see 3.2.3)bythehot-dip process. This material is commonly known as terne andis used where ease of solderability and a degree of corrosionresistance are desirable. It is especially suitable where resis-tance to gasoline
4、is required. Terne-coated sheet is also used forstamping, where the coating acts as a lubricant in the die,lessening difficulties in drawing. The weight of coating, alwaysexpressed as total coating on both sides, shall be specified inaccordance with Table 1.1.2 Material furnished under this specific
5、ation shall con-form to the applicable requirements of the latest issue ofSpecification A 924/A 924M, unless otherwise providedherein.1.3 Terne-coated steel is available in a number of designa-tions, types, and grades.1.4 This specification is applicable to orders in eitherinch-pound units (as A 308
6、) or SI units (as A 308M). Values ininch-pound and SI units are not necessarily equivalent. Withinthe text, SI units are shown in brackets. Each system shall beused independently of the other.1.5 Unless the order specifies the “M” designation (SIunits), the product shall be furnished to inch-pound u
7、nits.1.6 The text of this specification references notes andfootnotes that provide explanatory material. These notes andfootnotes, excluding those in tables and figures, shall not beconsidered as requirements of this specification.1.7 This standard does not purport to address all of thesafety concer
8、ns, 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:2A 309 Test Method for Weight and Composit
9、ion of Coatingon Terne Sheet by the Triple-Spot TestA 902 Terminology Relating to Metallic Coated Steel Prod-uctsA 924/A 924M Specification for General Requirements forSteel Sheet, Metallic-Coated by the Hot-Dip ProcessE 517 Test Method for Plastic Strain Ratio r for Sheet MetalE 646 Test Method for
10、 Tensile Strain-Hardening Exponents(n -Values) of Metallic Sheet Materials3. Terminology3.1 DefinitionsFor definitions of terms and abbreviationsused in this specification, see Terminology A 902.3.2 Definitions of Terms Specific to This Standard:3.2.1 electrolytic nickel plate, na nickel coating pre
11、depos-ited on steel sheet; used to promote a more uniform and morecorrosion-resistant hot-dipped, long terne coating.3.2.2 terne-coated sheet, nsteel sheet coated by immer-sion in molten terne metal; the steel sheet prior to immersion inthe terne metal is either bare (uncoated) or with a predeposite
12、delectrolytic nickel coating.3.2.3 terne metal, nan alloy of lead with a small percent-age of tin sufficient to obtain a smooth continuous coating.3.2.3.1 DiscussionThe minimum tin content is normally8 %, with higher percentages used depending on the type ofcoating equipment used.4. Classification4.
13、1 The material is available in four designations, as fol-lows:4.1.1 Commercial steel (CS Types A, B, and C),4.1.2 Deep drawing steel (DDS),1This specification is under the jurisdiction of ASTM Committee A05 onMetallic-Coated Iron and Steel Products and is the direct responsibility ofSubcommittee A05
14、.11 on Sheet Specifications.Current edition approved Nov. 15, 2006. Published January 2007. Originallyapproved in 1947. Last previous edition approved in 2003 as A 308/A 308M - 03.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org
15、. For Annual Book of ASTMStandards volume information, refer to the 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.
16、4.1.3 Extra deep drawing steel (EDDS), and4.1.4 Structural steel (SS).4.2 Structural steel is available in several grades.4.3 The material is available with several coating weightsmasses (coating designations) as shown in Table 1.5. Ordering Information5.1 Terne-coated sheet in coils or cut lengths
17、is produced tothickness requirements expressed to 0.001 in. 0.01 mm. Thethickness of the sheet includes both the base metal and thecoating.5.2 Orders for material under this specification shall includethe following information, as necessary, to describe adequatelythe required material:5.2.1 Name of
18、material (long terne-coated steel sheet),5.2.2 Designations of sheet steel (CS (Types A, B, and C)DDS, EDDS, and SS including grade or SS),5.2.2.1 When a CS type is not specified, Type B will befurnished.5.2.3 ASTM designation number and year of issue,5.2.4 Coating designation (see 8.1.1 and Table 1
19、),5.2.5 Nickel plating; specify with or without (if unspecified,the sheet steel would usually be supplied without nickelplating),5.2.6 Specify whether oiled or not oiled,5.2.7 Dimensions (show thickness, minimum or nominalwidth, and length, if cut length). The purchaser shall specifythe appropriate
20、table of thickness tolerances in SpecificationA 924/A 924M that applies to the order, that is, the table ofthickness tolerances for38-in. 10-mm edge distance, or thetable of thickness tolerances for 1-in. 25-mm edge distance.5.2.8 Coil size requirements (specify maximum outsidediameter (OD), accepta
21、ble inside diameter (ID), and maximumweight),5.2.9 Certification, if required, and heat analysis and me-chanical property report,5.2.10 Application (part identification and description), and5.2.11 Special requirements (if any).NOTE 1Typical ordering descriptions are as follows: terne-coatedsheet, De
22、ep Drawing Steel (DDS), ASTM A 308 ; coating desig-nation LT25, oiled 0.024 in. minimum by 32 in. by coil, 24 in. ID,15 000lb max for fuel tankupper half, or terne-coated sheet, DeepDrawing Steel (DDS), ASTM A 308Mcoating designation LTZ75, oiled,0.60 mm minimum by 810mm by coil, 600mm ID, 7000kg ma
23、x forfuel tank upper half.6. Chemical Composition, Base Metal6.1 The heat analysis of the base metal furnished under thisspecification shall conform to the requirements shown in Table2.6.1.1 Include in the report of the heat analysis, each of theelements in Table 2. When the amount of copper, nickel
24、,chromium, or molybdenum is less than 0.02 %, report theanalysis as 0.02 % or the actual determined value. When theamount of vanadium, titanium, or columbium is less than0.008 %, report the analysis as 0.008 % or the actual deter-mined value. When the amount of boron is less than 0.0005 %,report as
25、0.0005 % or the actual determined value.7. Mechanical Properties7.1 Structural steel sheet shall conform to the mechanicalproperty requirements in Table 3 for the type, grade, or classspecified, or combination thereof.7.2 The typical mechanical properties for CS (Types A, B,and C), DDS, and EDDS she
26、et designations are listed in Table4. These mechanical properties are nonmandatory. They areintended solely to provide the purchaser with as much infor-mation as possible to make an informed decision on the steel tobe specified. Values outside of these ranges are to be expected.7.3 When base metal m
27、echanical properties are required, alltests shall be conducted in accordance with the methodsspecified in Specification A 924/A 924M.7.4 Bending Properties:7.4.1 Minimum Cold-Bending RadiiStructural steel sheetis commonly fabricated by cold bending. There are manyinterrelated factors that affect the
28、 ability of a steel to cold formover a given radius under shop conditions. These factorsTABLE 1 Weight Mass of Coating (Total Both Sides)A,BNOTE 1Coating Thickness/Weight Mass EquivalenceThe coatingthickness may be estimated from the coating weight mass by using thefollowing relationship: 0.25 oz/ft
29、275 g/m2 total both sides (LT25LTZ75) is equal to 0.00027 in. or 0.27 mils 0.00508 mm total bothsides. This formula is not to be used for calculation of tensile strength ofthe base metal, which must be based on actual base metal thicknessmeasurement.CoatingDesignationMinimum RequirementsTriple-SpotT
30、estSingle-Spot TestInch-Pound Unitsoz/ft2oz/ft2LT01 no mini-mumCno mini-mumCLT25 0.25 0.20LT35 0.35 0.25LT40 0.40 0.30LT55 0.55 0.40LT85 0.85 0.70LT110 1.10 0.90SI Unitsg/m2g/m2LTZ01 no mini-mumCno mini-mumCLTZ75 75 60LTZ110 110 75LTZ120 120 90LTZ170 170 120LTZ260 260 215LTZ335 335 275AThe coating d
31、esignation number is the term by which this material is specified.The weight mass of coating in ounces per square foot grams per square metreof sheet refers to the total coating on both surfaces. Because of the many variablesand changing conditions that are characteristic of continuous terne coating
32、, theterne coating is not always evenly divided between the two surfaces of theterne-coated sheet, nor is the terne coating always evenly distributed from edge toedge. However, it can normally be expected that not less than 40 % of thesingle-spot check limit will be found on either surface.BAs the p
33、erformance for the long terne-coated sheet is related to the coatingthickness, material carrying the statement “meets ASTM A 308 A 308M require-ments” should also specify the particular coating designation.C“No minimum” means that there are no established minimum requirements fortriple- and single-s
34、pot tests.A 308/A 308M 062include: thickness, strength level, degree of restraint, relation-ship to rolling direction, chemistry, and base metal microstruc-ture. Table 5 lists the suggested minimum inside radius for 90cold bending for structural steel. They presuppose “hard way”bending (bend axis pa
35、rallel to rolling direction) and reasonablygood shop forming practices. Where possible, the use of largerradii or “easy way” bends are recommended for improvedperformance.8. Coating Properties8.1 Coating Weight Mass:8.1.1 Coating weight mass shall conform to the require-ments as shown in Table 1 for
36、 the specific coating designation.8.2 Coating Weight Mass Tests:8.2.1 Coating weight mass tests shall be performed inaccordance with the requirements stated in SpecificationA 924/ A 924M.8.2.2 The referee method to be used shall be Test MethodA 309.8.3 Coating Bend Test:TABLE 2 Chemical Requirements
37、AComposition, %Heat AnalysisElement, max (unless otherwise shown)Designation C Mn P S Al Cu Ni Cr Mo V Cb TiBNBCS Type AC,D,E0.10 0.60 0.030 0.035 . . . 0.20 0.20 0.15 0.06 0.008 0.008 0.025 . .CS Type BF,C0.020.15 0.60 0.030 0.035 . . . 0.20 0.20 0.15 0.06 0.008 0.008 0.025 . .CS Type CC,D,E0.08 0.
38、60 0.10 0.035 . . . 0.20 0.20 0.15 0.06 0.008 0.008 0.025 . .DDSD,E0.06 0.50 0.020 0.030 0.01,min0.20 0.20 0.15 0.06 0.008 0.008 0.025 . .EDDSG0.02 0.40 0.020 0.025 0.01,min0.20 0.20 0.15 0.06 0.10 0.10 0.15 . .SS:Grades 25, 30, 33 0.20 0.60 0.04 0.04 . . . 0.20 0.20 0.15 0.06 0.008 0.008 0.025 . .(
39、Type 1) and 80 . .Grade 40 (Type 1) 0.20 0.90 0.04 0.04 . . . 0.20 0.20 0.15 0.06 0.008 0.008 0.025 . .Grades 33 (Type 2) 0.15 0.60 0.20 0.04 . . . 0.20 0.20 0.15 0.06 0.008 0.008 0.025 . .and 40 (Type 2) . .AWhere an ellipsis (. . .) appears in the table, there is no requirement, but the analysis s
40、hall be reported.BFor steels containing more than 0.02 % carbon, titanium is permitted to 0.025 % provided the ratio of % titanium to % nitrogen does not exceed 3.4.CWhen a deoxidized steel is required for the application, the purchaser has the option to order CS and SS to a minimum of 0.01 % total
41、aluminum.DSteel is permitted to be furnished as a vacuum degassed or chemically stabilized steel, or both, at the producers option.EFor carbon levels less than or equal to 0.02 %, vanadium, columbium, or titanium, or combinations thereof, are permitted to be used as stabilizing elements at theproduc
42、ers option. In such cases, the applicable limit for vanadium and columbium shall be 0.10 % max. and the limit for titanium shall be 0.15 % max.FFor CS, specify Type B to avoid carbon levels below 0.02 %.GShall be furnished as a stabilized steel.TABLE 3 Mechanical Requirements, Base MetalAInch-Pound
43、UnitsStructural Steel (SS)GradeYield Strength,min, ksiTensileStrength,min, ksiElongation in2 in., min %25 25 42 2630 30 45 2433 (Types 1 and 2) 33 48 2240 (Types 1 and 2) 40 52 2080B80 82 . . .SI UnitsYield Strength,min, MPaTensileStrength,min, MPaElongation in50 mm, min %170 170 290 26205 205 310 2
44、4230 (Types 1 and 2) 230 330 22275 (Types 1 and 2) 275 360 20550 550 565 . . .ALongitudinal sample direction (for example, test sample taken in the directionof rolling).BOn the full-hard product, the yield point approaches the tensile strength andsince there is no halt in the gage or drop in the bea
45、m, the yield point shall be takenas the yield stress at 0.5 % extension under load. If hardness result is 85 HardnessRockwell B (HRB) or higher, no tension test is required.TABLE 4 Typical Ranges of Mechanical Properties(Nonmandatory) (Longitudinal Direction)A,BDesignationYield Strength Elongationin
46、 2 in. 50 mm, %rmValueCnValueDksi MPaCS Type A 20/40 140/275 $30EECS Type B 24/42 165/290 $28CS Type C 20/40 140/275 $30EEDDSF22/35 150/240 $36 1.3/1/7 0.17/0.22EDDSG15/25 105/170 $40 1.7/2.1 0.23/0.27AThe typical mechanical property values presented here are nonmandatory.They are intended solely to
47、 provide the purchaser with as much information aspossible to make an informed decision on the steel to be specified.BThese typical mechanical properties apply to the full range of steel sheetthicknesses. The yield strength tends to increase and some of the formabilityvalues tend to decrease as the
48、steel sheet thickness decreases.CrmValueAverage plastic strain rates as determined by Test Method E 517.Dn ValueStrain hardening exponent as determined by Test Method E 646.ENo typical mechanical properties have been established.FThe DDS designation encompasses the previous drawing quality, special
49、killedproduct.GFurnish EDDS as a stabilized steel. It will be free from changes in mechanicalproperties over time, that is, nonaging.TABLE 5 Coating Bend Test RequirementsDesignation GradeRatio of the Inside BendDiameter to Thickness of theSpecimen (Any Direction)Structural steel 25 17012 tStructural steel 30 205 1tStructural steel 33 230 (Types 1and 2)112 tStructural steel 40 275 (Types 1and 2)2tStructural steel 80 550 not applicableA 308/A 308M 0638.3.1 For all designations other than structural st
