1、Designation: A 684/A 684M 08Standard Specification forSteel, Strip, High-Carbon, Cold-Rolled1This standard is issued under the fixed designation A 684/A 684M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last revisio
2、n. A number in parentheses indicates the year of last reapproval.A superscript epsilon () 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 covers cold-rolled, high-carb
3、on stripin coils or cut lengths. Strip is classified as product that is0.3000 in. 7.6 mm or less in thickness and over12 to 231516in. 12.5 to 600 mm in width, inclusive. Strip toleranceproducts may be available in widths wider than 231516 in. (600mm) by agreement between purchaser and supplier; howe
4、ver,such products are technically classified as cold-rolled sheet.The maximum of the specified carbon range is over 0.25 to1.35 %, inclusive. It is furnished in the following types asspecified:1.1.1 Soft spheroidized annealed high-carbon steel is in-tended for applications requiring maximum cold for
5、ming. It isnormally produced to give the lowest maximum Rockwellhardness for each grade.1.1.2 Soft annealed high-carbon steel is intended for appli-cations requiring moderate cold forming. It is produced to amaximum Rockwell hardness.1.1.3 Intermediate hardness high-carbon steel is intendedfor appli
6、cations where cold forming is slight or a stiff, springyproduct is needed, or both. It is produced to specified Rockwellhardness ranges, the maximum being higher than obtained forthe annealed type.1.1.4 Full hard high-carbon steel is intended for flat appli-cations. It is produced to minimum Rockwel
7、l hardness require-ments, which vary with grade, microstructure and gauge. Fullhard can be produced with either a pearlitic or spheroidizedmicrostructure or a mixture of both. The minimum hardnessshould be established between the consumer and the producer.1.2 This specification is applicable for ord
8、ers in eitherinch-pound units or SI units.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two
9、systems may result in non-conformancewith the standard.1.4 The tolerances in this specification are different thanthose in Specification A 568/A 568M and Specification A 109/A 109M.1.5 For the purpose of determining conformance with thisspecification, values shall be rounded to the nearest unit in t
10、heright hand place of figures used in expressing the limitingvalues in accordance with the rounding method of PracticeE29.1.6 This specification is expressed in both inch-pound unitsand SI units. However, unless the order specifies the applicable“M” specification designation (SI units), the material
11、 shall befurnished to inch-pound units. The metric portions of the tablesherein list permissible variations in dimensions and mass (seeNote 1) in SI (metric) units. The values listed are not exactconversions of the values listed in the inch-pound tables butinstead are rounded or rationalized values.
12、 Conformance to SItolerances is mandatory when the “M” specification is used.NOTE 1The term weight is used when inch-pound units are thestandard. However, under SI the preferred term is mass.2. Referenced Documents2.1 ASTM Standards:2A 109/A 109M Specification for Steel, Strip, Carbon (0.25Maximum P
13、ercent), Cold-RolledA 370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA 568/A 568M Specification for Steel, Sheet, Carbon,Structural, and High-Strength, Low-Alloy, Hot-Rolled andCold-Rolled, General Requirements forA 700 Practices for Packaging, Marking, and LoadingMethods fo
14、r Steel Products for ShipmentA 751 Test Methods, Practices, and Terminology forChemical Analysis of Steel ProductsA 941 Terminology Relating to Steel, Stainless Steel, Re-lated Alloys, and FerroalloysE3 Guide for Preparation of Metallographic SpecimensE29 Practice for Using Significant Digits in Tes
15、t Data toDetermine Conformance with Specifications1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.19 on Steel Sheet and Strip.Current edition approved Oct. 1, 2008. Published October 2
16、008. Originallyapproved in 1973. Last previous edition approved in 2006 as A 684/A 684M 06.2For 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 Su
17、mmary 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.E 112 Test Methods for Determining Average Grain SizeE 527 Practice for Numbering Metals
18、and Alloys in theUnified Numbering System (UNS)2.2 Federal Standards:Fed. Std. No. 123 Marking for Shipments (Civil Agencies)3Fed. Std. No. 183 Continuous Identification Marking of Ironand Steel Products32.3 Military Standard:MIL-STD-129 Marking for Shipping and Storage32.4 SAE Standard:J 1086 Recom
19、mended Practice for Numbering Metals andAlloys (UNS)43. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 burrmetal displaced beyond the plane of the surfaceby slitting or shearing.3.1.2 lotquantity of material of the same type, size, andfinish produced at one time from the same ca
20、st or heat, and heattreated in the same heat-treatment cycle.3.1.3 spheroidizingthe heating and cooling of the strip incontrolled conditions (annealing) to produce a spheroidal orglobular form of carbide microconstituent.3.1.4 stretcher strainselongated markings that appear onthe surface of the stri
21、p when dead soft (fully annealed) materialis deformed beyond its yield point (see 5.2).3.2 Refer to Terminology A 941 for additional terms used inthis standard.4. Ordering Information4.1 Orders for material under this specification shall includethe following information:4.1.1 ASTM designation and da
22、te of issue,4.1.2 Name, type, and steel grade number,4.1.3 Hardness (if intermediate or restricted hardness isspecified),4.1.4 Decarburization (if required),4.1.5 Application,4.1.6 Dimensions,4.1.7 Coil size requirements,4.1.8 Edge (indicate No. 1 round, square, etc.),4.1.9 Finish (indicate and spec
23、ify),4.1.10 Conditions (specify whether material is oiled or dry),4.1.11 Package (bare coils, skid, etc.),4.1.12 Cast or heat (formerly ladle) analysis report (ifrequired), and4.1.13 Special requirements (if required).4.2 Products covered by this specification are produced todecimal thickness only,
24、and decimal thickness tolerances apply.NOTE 2A typical ordering description is as follows: ASTM A 684dated _ Cold Rolled, High-Carbon Soft, Strip, Spheroidized 1064,0.042 in. by 6 in. by coil (16 in. ID by 40 in. OD max), No. 5 Edge, No.2 Finish, Oiled, Bare Skid or “ASTM A 684 dated _ Cold Rolled,H
25、igh-Carbon, Soft, Strip, Spheroidized 1064, 0.6 mm by 200 mm by coil(400 mm ID by 7500 mm OD max), No. 3 Edge, No. 2 Finish, Oiled, BareSkid.”5. Manufacture5.1 Condition:5.1.1 The strip shall be furnished cold rolled spheroidizedannealed, soft annealed, intermediate hardness, or full hard, asspecifi
26、ed.5.1.2 Intermediate hardness may be obtained by eitherrolling the strip after final annealing or by varying theannealing treatment, or both.5.2 Pinch PassSpheroidized annealed and annealed ma-terial may be pinch rolled after the final anneal to improveflatness, uniformly oil, modify surface, obtai
27、n proper mechani-cal properties and minimize stretcher strains if required by thepurchaser.6. Chemical Requirements6.1 Limits:6.1.1 When carbon steel strip is specified to chemicalcomposition, the compositions are commonly prepared usingthe ranges and limits shown in Table 1. The elements compris-in
28、g the desired chemical composition are specified in one ofthree ways:6.1.1.1 By a maximum limit,6.1.1.2 By a minimum limit, or6.1.1.3 By minimum and maximum limits, termed the“range.” By common usage, the range is the arithmeticaldifference between the two limits (for example, 0.60 to 0.71 is0.11 ra
29、nge).6.1.2 Steel grade numbers indicating chemical compositioncommonly produced to this specification are shown in Table 2and may be used. Table 3 shows requirements for additionalelements.6.1.3 Additional elements may be present. Limits on suchelements are by agreement between purchaser and supplie
30、r.6.1.3.1 Any additional elements specified shall be includedin the report of heat analysis.6.2 Heat (Formerly Ladle) Analysis:6.2.1 An analysis of each heat of steel shall be made by themanufacturer to determine the percentage of elements specifiedor restricted by the applicable specification.6.2.2
31、 When requested, heat analysis for elements listed orrequired shall be reported to the purchaser or to his represen-tative. Each of the elements listed in Tables 2 and 3 andadditional elements agreed upon by the purchaser and thesupplier shall be included in the report of heat analysis. When3Availab
32、le from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http:/www.dodssp.daps.mil.4Available from Society of Automotive Engineers (SAE), 400 CommonwealthDr., Warrendale, PA 15096-0001, http:/www.sae.org.TABLE 1 Rockwell Hardness Testing
33、 Ranges for Cold-RolledHigh-Carbon Steel StripRockwell “B” and “T” Scales Rockwell “C” and “N” ScalesThickness Scale Thickness ScaleOver 0.030 in.over 0.8 mmB Over 0.040 in.over 1.0 mmC0.020 to 0.030 in.0.5 to 0.8 mm30T 0.025 to 0.040 in.0.6 to 1.0 mm30NUnder 0.020 in.under 0.5 mm15T Under 0.025 in.
34、under 0.6 mm15NA 684/A 684M 082the amount of copper, nickel, chromium, or molybdenum isless than 0.02 %, the analysis may be reported as 0.02 %.When the amount of vanadium, columbium, or titanium is lessthan 0.008 %, the analysis may be reported as 0.008 %. Thereported heat analysis shall conform to
35、 the chemical composi-tion requirements of the appropriate grade in Table 2, if used,the additional elements in Table 3, and the limits of any otherelements agreed upon by the purchaser and supplier.6.3 Product AnalysisProduct analysis is the chemicalanalysis of the semi-finished product form. The s
36、trip may besubjected to product analysis by the purchaser either for thepurpose of verifying that the ordered chemical composition iswithin specified limits for each element as listed in Table 4including applicable tolerance for product analysis, or todetermine variations in compositions within a ca
37、st or heat.Table 5 lists additional chemical composition requirements.The results of analyses taken from different pieces within aheat may differ from each other and from the cast analysis. Thechemical composition thus determined shall not vary from thelimits specified by more than the amounts shown
38、 in Table 6.6.4 Methods of AnalysisTest Methods, Practices, andTerminology A 751 shall be used for referee purposes.7. Metallurgical Structure7.1 Grain Size:7.1.1 Unless otherwise specified, the steel strip shall bemanufactured to a fine grain (austenitic and ferritic) practice.7.1.2 Pearlite is the
39、 normal structure of cold rolled high-carbon strip unless it has had an intermediate anneal.7.2 Decarburization:7.2.1 When specified, the steel strip shall have a maximumpermissible depth of complete plus partial decarburization of0.001 in. 0.025 mm or 1.5 % of the thickness of the strip,whichever i
40、s greater, except that strip less than 0.011 in. 0.279mm thick shall show no complete decarburization.7.3 Annealed is mostly a spheroidized structure, but maycontain some vestiges of pearlite.7.4 Spheroidized annealed is essentially free of pearlite.7.5 At least one specimen shall be taken from each
41、 lot formicroexamination.7.5.1 The specimens shall be prepared for microscopicexamination in accordance with Guide E3.8. Mechanical Requirements8.1 Unless otherwise specified in the applicable productspecification, test specimens must be prepared in accordancewith Test Methods and Definitions A 370.
42、8.2 Mechanical tests shall be conducted in accordance withTest Methods and Definitions A 370.8.3 Hardness:8.3.1 Spheroidized Annealed and Annealed TypesWhenfurnished spheroidized annealed or annealed, the hardness ofthe strip shall not exceed the maximum values specified inFigs. 1 and 2 for the appl
43、icable carbon range and type.8.3.2 Intermediate Hardness TypeWhen furnished as in-termediate hardness, the hardness of the strip shall conform tothe range specified on the purchase order. The maximumhardness limit and the corresponding minimum shall be speci-fied by the purchaser. If the maximum tem
44、per is underRockwell B 100 (15T93 or 30T82), that scale should be usedexclusively. If the minimum temper is over Rockwell C 20(15N69.5 or 30N41.5), that scale should be used exclusively.For accuracy in testing, the hardness scales should not overlap.On either hardness scale, a range of ten points ar
45、ithmeticdifference is required. Refer to Table 1 for appropriate scaletesting requirements.8.3.3 Full hard is specified to a minimum hardness value.Refer to Table 1 for appropriate scale testing requirements.8.3.4 At least one specimen shall be taken from each lot.8.3.5 The sample shall be tested in
46、 accordance with TestMethods and Definitions A 370.8.4 Bend Test:8.4.1 The steel strip produced as spheroidized, or theannealed type shall meet the cold bend requirement in Table 2.Any visible cracking on the tension side of the bend portionshall be cause for rejection.8.4.2 At least one specimen sh
47、all be taken from each lot.8.4.3 The specimen shall be the full thickness and shall betaken transverse to the rolling direction as described in TestTABLE 2 Cold Bending RequirementsA,Bfor Spheroidized,Annealed, and Soft-Annealed Cold-Rolled Carbon Steel StripTypeDegree ofBendInsideRadius toThickness
48、Relation of BendTest Specimen toRolling DirectionAnnealed 180 3t transverseCSpheroidized 180 2t transverseCAUp to 0.100 in. 2.5 mm, incl, thickness maximum. When bend radius forthickness is over 0.100 in. 2.5 mm the producer should be consulted. These ratiosapply to bending performance of the test s
49、pecimen.BThese bend tests apply to the bending performance of test specimens only.Where material is to be bent in fabricating operations a more liberal bend radiusmay be required and should be based on prior experience or consultation with thesteel producer, or both.CIf finished strip width prohibits taking a transverse bend test specimen, alongitudinal specimen may be substituted, except the bend radius shall be reducedby 1 t.TABLE 3 Heat (Formerly Ladle) Analysis Limits and RangesElementStandard Chemical Limitsand Ranges, Limit
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