1、Designation: A242/A242M 04 (Reapproved 2009)A242/A242M 13 American Association StateHighway and Transportation OfficialsStandard AASHTO No.: M 161Standard Specification forHigh-Strength Low-Alloy Structural Steel1This standard is issued under the fixed designation A242/A242M; the number immediately
2、following the designation indicates the yearof original adoption or, in the case of 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.This standard has been a
3、pproved for use by agencies of the Department of Defense.1. Scope Scope*1.1 This specification covers high-strength low-alloy structural steel shapes, plates, and bars for welded, riveted, or boltedconstruction intended primarily for use as structural members where savings in weight mass or added du
4、rability are important.The atmospheric corrosion resistance of the steel in most environments is substantially better than that of carbon structural steelswith or without copper addition. When properly exposed to the atmosphere, this steel can be used bare (unpainted) for manyapplications (see Note
5、1). This specification is limited to material up to 4 in. 100 mm, inclusive, in thickness.NOTE 1For methods of estimating the atmospheric corrosion resistance of low-alloy steels, see Guide G101.1.2 When the steel is to be welded, it is presupposed that a welding procedure suitable for the grade of
6、steel and intended useor service will be utilized. See Appendix X3 of Specification A6/A6M for information on weldability.1.3 The values stated in either inch-pound units or SI units are to be regarded as standard. Within the text, the SI units are shownin brackets. The values stated in each system
7、are not exact equivalents; therefore, each system must be used independently of theother. Combining values from the two systems may result in nonconformance with the specification.1.4 For structural products produced from coil and furnished without heat treatment or with stress relieving only, the a
8、dditionalrequirements, including additional testing requirements and the reporting of additional test results, of Specification A6/A6M apply.2. Referenced Documents2.1 ASTM Standards:2A6/A6M Specification for General Requirements for Rolled Structural Steel Bars, Plates, Shapes, and Sheet PilingG101
9、 Guide for Estimating the Atmospheric Corrosion Resistance of Low-Alloy Steels3. General Requirements for Delivery3.1 Structural products furnished under this specification shall conform to the requirements of the current edition ofSpecification A6/A6M, for the specific structural product ordered, u
10、nless a conflict exists, in which case this specification shallprevail.3.2 Coils are excluded from qualification to this specification until they are processed into a finished structural product.Structural products produced from coil means structural products that have been cut to individual lengths
11、 from a coil. Theprocessor directly controls, or is responsible for, the operations involved in the processing of a coil into a finished structuralproduct. Such operations include decoiling, leveling or straightening, hot-forming or cold-forming (if applicable), cutting to length,testing, inspection
12、, conditioning, heat treatment (if applicable), packaging, marking, loading for shipment, and certification.NOTE 2For structural products produced from coil and furnished without heat treatment or with stress relieving only, two test results are to be reportedfor each qualifying coil. Additional req
13、uirements regarding structural products produced from coil are described in Specification A6/A6M.4. Materials and Manufacture4.1 The steel shall be semi-killed or killed.1 This specification is under the jurisdiction ofASTM Committee A01 on Steel, Stainless Steel and RelatedAlloys and is the direct
14、responsibility of Subcommittee A01.02on Structural Steel for Bridges, Buildings, Rolling Stock and Ships.Current edition approved April 1, 2009May 1, 2013. Published May 2009June 2013. Originally approved in 1941. Last previous edition approved in 20042009 asA242/A242M041. DOI: 10.1520/A0242_A0242M-
15、04R09. 04 (2009). DOI: 10.1520/A0242_A0242M-13.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document
16、is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appro
17、priate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*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 Stat
18、es15. Chemical Composition5.1 The heat analysis shall conform to the requirements prescribed in Table 2.5.2 The steel shall conform on product analysis to the requirements prescribed in Table 2, subject to the product analysistolerances in Specification A6/A6M.5.3 Choice and use of alloying elements
19、, combined with carbon, manganese, phosphorus, sulfur, and copper within the limitsprescribed in 5.1 to give the mechanical properties prescribed in Section 6 and to provide the atmospheric corrosion resistance of1.1, shall be made by the manufacturer and included and reported in the heat analysis t
20、o identify the type of steel applied. Elementscommonly added include: chromium, nickel, silicon, vanadium, titanium, and zirconium.5.4 The atmospheric corrosion-resistance index, calculated on the basis of the heat analysis of the steel, as described in GuideG101Predictive Method Based on the Data o
21、f Larabee and Coburn, shall be 6.0 or higher.NOTE 3The user is cautioned that the Guide G101 predictive equation (Predictive Method Based on the Data of Larabee and Coburn) for calculationof an atmospheric corrosion-resistance index has only been verified for the composition limits stated in the gui
22、de.5.5 When required, the manufacturer shall supply evidence of corrosion resistance satisfactory to the purchaser.6. Tension Test6.1 The material as represented by the test specimens shall conform to the requirements as to tensile properties prescribed inTable 1.7. Keywords7.1 atmospheric corrosion
23、 resistance; bars; bolted construction; durability; high-strength; low-alloy; plates; riveted construction;shapes; steel; structural steel; weight; welded constructionSUPPLEMENTARY REQUIREMENTSStandardized supplementary requirements for use at the option of the purchaser are listed inSpecification A
24、6/A6M. Those that are considered suitable for use with this specification are listed bytitle:TABLE 1 Tensile RequirementsPlates and BarsA Structural ShapesFor thicknesses34 in.20 mm,andunderFor thicknessesover34 to 112 in.20 to 40mm, inclFor thicknessesover112 to 4 in.40 to 100mm, inclFor flange orl
25、eg thicknesses1.5 in. 40 mmand underFor flangethicknessesover 1.5 in.40 mm to2 in. 50mm, inclFor flangethicknessesover 2 in.50 mmTensile strength, min, ksi MPa 70 480 67 460 63 435 70 485 67 460 63 435Yield point, min, ksi MPa 50 345 46 315 42 290 50 345 46 315 42 290Elongation in 8 in. 200 mm, min,
26、 % 18B,C 18B,C 18B,C 18C 18 18Elongation in 2 in. 50 mm, min, % 21C 21C 21C 21 21 21DA See the Orientation subsection in the Tension Tests section of Specification A6/A6M.B Elongation not required to be determined for floor plate.C For plates wider than 24 in. 600 mm the elongation requirement is re
27、duced two percentage points. See the Elongation Requirement Adjustments subsection in theTension Tests section of Specification A6/A6M.D For wide flange shapes over 426 lb/ft 634 kg/m, elongation in 2 in. 50 mm of 18 % minimum applies.TABLE 2 Chemical Requirements (Heat Analysis)Element Composition,
28、 %Type 1Carbon, max 0.15Manganese, max 1.00Phosphorus, max 0.15Sulfur, max 0.05Copper, min 0.20A242/A242M 132S2. Product Analysis,S3. Simulated Post-Weld Heat Treatment of Mechanical Test Coupons,S5. Charpy V-Notch Impact Test,S6. Drop Weight Test (for Material 0.625 in. 16 mm and over in Thickness)
29、,S8. Ultrasonic Examination, andS15. Reduction of Area Measurement.S32. Single Heat Bundles.SUMMARY OF CHANGESCommittee A01 has identified the location of selected changes to this standard since the last issue(A242/A242M 04 (2009) that may impact the use of this standard. (Approved May 1, 2013.)(1)
30、Revised 4.1 to require killed steels.ASTM International takes no 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 ri
31、skof infringement of such rights, are entirely their own responsibility.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 thi
32、s 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
33、your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).A242/A242M 133
