1、Designation: A434/A434M 18Standard Specification forSteel Bars, Alloy, Hot-Wrought or Cold-Finished, Quenchedand Tempered1This standard is issued under the fixed designation A434/A434M; the number immediately following the designation indicates the yearof original adoption or, in the case of revisio
2、n, 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 approved for use by agencies of the U.S. Department of Defense.1. Scope*1.1 This specificati
3、on covers hot-wrought and cold-finishedquenched and tempered alloy steel bars.1.2 Hot-wrought bars are available in three strength levelclasses designated BB, BC, and BD, and cold-finished bars intwo strength level classes designated BB and BC. The bars areavailable in the conditions specified in 4.
4、4 subject to the sizelimitations shown.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 sys
5、tems may result in non-conformancewith the standard.1.4 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
6、by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2A29/A29M Specification for General Requirements for SteelBars, Carbon and Alloy, Hot-WroughtA108 Specification for Steel Bar, Carbon and Alloy, Cold-FinishedA370 Test Methods and Def
7、initions for Mechanical Testingof Steel Products3. Ordering Information3.1 Orders for material under this specification shouldinclude the following information:3.1.1 Quantity (weight or number of pieces),3.1.2 Name of material (heat-treated alloy steel bars),3.1.3 Method of finish (condition) (4.4),
8、3.1.4 Dimensions, including length (if hot-wrought bars arefor cold finishing, the cold-finished size should also bespecified),3.1.5 ASTM designation and date of issue,3.1.6 Chemical composition grade (Section 5),3.1.7 Strength class (Table 1),3.1.8 Test report, if required (Section 11),3.1.9 Supple
9、mentary Requirements or Special Require-ments, if required, and3.1.10 End use.NOTE 1A typical ordering description is as follows: 10 000 lb,Heat-Treated Alloy Steel Bars, Hot Rolled, 1.000 in. diameter 10 ft,ASTM A434 dated _, Grade 4140, Class BB, Test Report Required,Motor Shafts.4. Materials and
10、Manufacture4.1 Melting PracticeThe steel shall be made by anycommercially viable primary steelmaking process. The pri-mary melting may incorporate separate degassing or refiningand may be followed by secondary melting using electroslagremelting or vacuum arc remelting. Where secondary meltingis empl
11、oyed, the heat shall be defined as all of the ingotsremelted from a single primary heat.4.2 DiscardSufficient discard shall be made to securefreedom from injurious piping and undue segregation.4.3 Slow CoolingHot-wrought alloy bars shall, immedi-ately after rolling, be allowed to cool to a temperatu
12、re belowthe critical range under suitable conditions to prevent injury bytoo rapid cooling.4.4 ConditionBars shall be furnished in one of the follow-ing conditions, as specified by the purchaser. Generally, sizelimits for various methods of processing round bars are:1This specification is under the
13、jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.15 on Bars.Current edition approved July 1, 2018. Published July 2018. Originally approvedin 1959. Last previous edition approved in 2017 as A434/A434M17. DOI:10.1520/A0
14、434_A0434M18.2For 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 Summary page onthe ASTM website.*A Summary of Changes section appears at the end
15、 of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDev
16、elopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1Hot-wrought or hot-wrought descaled 912 in. 241.3 mm, maxCold-drawn18 to 4 in. 3.2 to 102 mm, inclCold-drawn, ground, and polished18 to 4 in. 3.2 to 102
17、 mm, inclTurned and polished34 to 9 in. 19.1 to 229 mm, inclTurned, ground, and polished34 to 9 in. 19.1 to 229 mm, incl4.5 Heat Treatment:4.5.1 Heat treatment shall include quenching and temperingfor all classes of material. The material shall be uniformlyheated to the austenitizing temperature, so
18、aked for a sufficientlength of time to produce the desired structure (a lot thusheated being known as a “quenching charge”), and quenched ina suitable medium under substantially uniform conditions foreach quenching charge. The material shall then be uniformlyreheated to the proper temperature for te
19、mpering (a lot thusreheated being known as a “tempering charge”), and allowed tocool uniformly. The temperature selected for tempering shallbe not less than 800 F 427 C.4.5.2 Material cold drawn after heat treatment shall be stressrelieved, when this is necessary, in order to meet the specifiedmecha
20、nical properties.4.5.3 Cold-finished bars may be stress relieved afterstraightening.4.5.4 For heat-treated hot-wrought bars, where it is desir-able to minimize internal stresses introduced by machinestraightening, the purchaser may specify a stress relief as afinal operation.4.5.5 If warpage occurs
21、in the stress-relieving operation, thebars may be restraightened without further stress-relieving,provided they meet the required mechanical properties.5. Chemical Composition5.1 The grade of steel furnished shall be specified by thepurchaser and shall be selected from the standard alloy gradesin Ta
22、ble 2 of Specification A29/A29M, or to such othercompositions as may be specified using the ranges and limits inTable 4 of Specification A29/A29M.5.2 In all cases, the grade specified shall be capable ofdeveloping the required mechanical properties. If, in theopinion of the manufacturer, the grade s
23、pecified is not capableof developing the mechanical properties, the manufacturershall notify the purchaser and whenever possible suggest analternative grade.5.3 Representative grade types listed for the respectiveclasses and bar sizes in Table 1 are for information only.6. Grain Size6.1 RequirementT
24、he steel shall conform to the fine auste-nitic grain size requirement of Specification A29/A29M.7. Mechanical Properties7.1 RequirementsThe material, as represented by testspecimens, shall conform to the tensile properties in Table 1 forthe class specified.7.2 Specimens:7.2.1 Test specimens shall be
25、 taken longitudinally after finalprocessing.7.2.2 Test specimens shall be selected from the locationsand prepared for testing as specified in Test Methods andDefinitions A370.7.3 Number of TestsOne tension test shall be made fromeach tempering or stress-relieving charge. If more than onequenching ch
26、arge is represented, one tension test shall be madefrom each quenching charge. If more than one heat is repre-sented in a quenching charge, one tension test shall be madefrom each heat and size. For continuous-type treatment, onetension test shall be made for each 25 tons 22.7 Mg of eachheat or size
27、.7.4 Test MethodTension tests shall be made in accordancewith Test Methods and Definitions A370 using the 0.2 % offsetmethod when determining yield strength.TABLE 1 Tensile PropertiesNOTE 1The mechanical properties of hot-wrought bars ordered for cold finishing, shall be governed by the cold-finishe
28、d size.Class Diameter, in. mmYield Strength, min,ksi MPaATensile Strength,min, ksi MPaElongation in2 in. or 50mm, min, %Reductionof Area,min, %SAE or AISIRepresentativeGrade TypesB112 38.1 and under 90 620 110 760 20 5063100, 4100,Over 112 to 212 38.1 to 63.5, incl 80 550 105 720 20 50 8600, 8700BBC
29、Over 212 to 4 63.5 to 102, incl 75 520 100 690 20 50Over 4 to 7 102 to 178, incl 75 520 95 660 20 50Over 7 to 10 178 to 254, incl 65 450 90 620 18 40112 38.1 and under 110 760 130 900 16 50J3100, 4100, 6100,Over 112 to 212 38.1 to 63.5, incl 105 720 125 860 16 50 8600, 8700BCCOver 212 to 4 63.5 to 1
30、02, incl 95 660 115 790 16 45Over 4 to 7 102 to 178, incl 85 590 110 760 16 45J3100, 4100Over 7 to 10 178 to 254, incl 80 550 105 720 15 40 4300, 9800112 38.1 and under 130 900 155 1070 14 3564100, 4300,Over 112 to 212 38.1 to 63.5, incl 120 830 150 1030 14 35 9800BDCOver 212 to 4 63.5 to 102, incl
31、110 760 140 960 14 35Over 4 to 7 102 to 178, incl 105 720 135 930 14 35Over 7 to 10 178 to 254, incl 100 690 130 900 14 35ADetermined by the 0.2 % offset method.BThe carbon content of all steels listed in this column may vary up to 0.55 % max, as agreed upon by the manufacturer and the purchaser.CCl
32、ass BB, BC, BD hot-wrought; Class BB, BC cold-finished.A434/A434M 1828. Permissible Variation of Dimensions8.1 Special StraightnessUnless otherwise specified, allmaterial shall be supplied to a straightness tolerance of18 in.3.18 mm in any 5 ft 1.5 m, but may not exceed thefollowing:Maximum straight
33、ness deviation, in. 5 1/8 3 length in feet/5!9. Workmanship, Finish, and Appearance9.1 WorkmanshipThe bars shall be free of pipe, cracks,and flakes. Within the limits of good manufacturing andinspection practices, the bars shall be free of injurious seams,laps, segregation, or other imperfections wh
34、ich, due to theirnature, degree, or extent, will interfere with the use of thematerial in machining or fabrication of suitable parts.9.2 OilingUnless otherwise specified, hot-wrought des-caled bars and cold-finished bars shall be given a surfacecoating of oil or other rust inhibitor to protect again
35、st rustduring shipment.10. General Requirements10.1 Material furnished under this specification shall con-form to the applicable requirements for the current edition ofSpecification A29/A29M or Specification A108.11. Certification and Report of Testing11.1 When specified by the purchaser, a manufact
36、urerscertification that the material was manufactured and tested inaccordance with this specification together with a report of theheat analysis, grain size, and tensile requirement test resultsshall be furnished. The report shall include the name of themanufacturer, ASTM designation number and year
37、 date andrevision letter, if any, grade, class, heat number, and size.11.2 When Supplementary Requirement S1 is specified, thereport shall include a statement of compliance with therequirement or the results of tests when the requirementinvolves measured test values.12. Keywords12.1 alloy steel bars
38、; cold-finished steel bars; hot-wroughtsteel bars; quenched and tempered steel bars; steel barsSUPPLEMENTARY REQUIREMENTSThe following supplementary requirement shall be applied only when specified by the purchaser inthe inquiry, contract, or order. Details of this supplementary requirement shall be
39、 agreed upon inwriting by the manufacturer and purchaser. Supplementary requirements shall in no way negate anyrequirements of the specification itself.S1. Hardness TestS1.1 Maximum surface Brinell hardness, if specified by thepurchaser, shall be as agreed upon between the manufacturerand the purcha
40、ser.SUMMARY OF CHANGESCommittee A01 has identified the location of selected changes to this standard since the last issue(A434/A434M17) that may impact the use of this standard. (Approved July 1, 2018.)(1) Deleted Test Methods E112 from 2.1.(2) Revised first sentence of 4.1.(3) Revised 6.1.(4) Delet
41、ed 6.2, 6.3, and 6.4.Committee A01 has identified the location of selected changes to this standard since the last issue(A434/A434M15) that may impact the use of this standard. (Approved March 15, 2017.)(1) In Diameter column of Table 1, the metric conversion for4 in. was corrected.A434/A434M 183AST
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