1、Designation: A434/A434M 15Standard 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.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 Definitions for Mechanical
6、 Testingof Steel ProductsE112 Test Methods for Determining Average Grain Size3. 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
7、 of finish (condition) (4.4),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 requi
8、red (Section 11),3.1.9 Supplementary 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,M
9、otor Shafts.4. Materials and Manufacture4.1 Melting PracticeThe steel shall be made by one ormore of the following primary processes: open-hearth, basic-oxygen, or electric-furnace. The primary melting may incor-porate separate degassing or refining and may be followed bysecondary melting using elec
10、troslag remelting or vacuum arcremelting. Where secondary melting is employed, the heatshall be defined as all of the ingots remelted from a singleprimary heat.4.2 DiscardSufficient discard shall be made to securefreedom from injurious piping and undue segregation.4.3 Slow CoolingHot-wrought alloy b
11、ars shall, immedi-ately after rolling, be allowed to cool to a temperature 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 variou
12、s methods of processing round bars are:Hot-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 mm, inclTurned and polished34 to 9 in. 19.1 to 229 mm, inclTurned, ground, and polished34 to 9 in. 19.1 to 2
13、29 mm, incl4.5 Heat Treatment:4.5.1 Heat treatment shall include quenching and temperingfor all classes of material. The material shall be uniformly1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of Subc
14、ommitteeA01.15 on Bars.Current edition approved Nov. 1, 2015. Published November 2015. Originallyapproved in 1959. Last previous edition approved in 2012 as A434 06(2012).DOI: 10.1520/A0434_A0434M-15.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Servic
15、e 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 of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-29
16、59. United States1heated to the austenitizing temperature, soaked 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 sha
17、ll then be uniformlyreheated to the proper temperature for tempering (a lot thusreheated being known as a “tempering charge”), and allowed tocool uniformly. The temperature selected for tempering shallbe not less than 800F 427C.4.5.2 Material cold drawn after heat treatment shall be stressrelieved,
18、when this is necessary, in order to meet the specifiedmechanical 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
19、 stress relief as afinal operation.4.5.5 If warpage occurs 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 thepurchase
20、r and shall be selected from the standard alloy gradesin Table 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 pro
21、perties. If, in theopinion of the manufacturer, the grade specified 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 Tab
22、le 1 are for information only.6. Grain Size6.1 RequirementThe bars shall have an austenitic grainsize of 5 and finer. The grain structure shall be consideredsatisfactory if 70 % is within the specified size limits.6.2 SpecimensGrain size specimens shall be taken inaccordance with Test Methods E112.6
23、.3 Number of TestsNot less than one grain size test shallbe made per heat.6.4 Test MethodGrain size shall be determined in accor-dance with the Comparison Method of Test Methods E112.7. Mechanical Properties7.1 RequirementsThe material, as represented by testspecimens, shall conform to the tensile p
24、roperties in Table 1 forthe class specified.7.2 Specimens:7.2.1 Test specimens shall be 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 sh
25、all be made fromeach tempering or stress-relieving charge. If more than onequenching charge 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-typ
26、e treatment, onetension test shall be made for each 25 tons 22.7 Mg of eachheat or size.TABLE 1 Tensile PropertiesNOTE 1The mechanical properties of hot-wrought bars ordered for cold finishing, shall be governed by the cold-finished size.Class Diameter, in. mmYield Strength, min,ksi MPaATensile Stre
27、ngth,min, ksi MPaElongationin 2 in. or50 mm,min, %Reductionof Area,min, %SAE or AISI Repre-sentativeGrade 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, 8700BBCOver 212 to 4 63.5 to 114, incl 75 520 100 690 20 50Over 4 to 7 114
28、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 114, incl 95 660 115 790 16 45Over 4 to 7 114 to 178, incl 85 590 110
29、 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 114, incl 110 760 140 960 14 35Over 4 to 7 114 to 178, incl 105 720 135 930 14
30、 35Over 7 to 10 178 to 254, incl 100 690 130 900 14 35AThe 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.BDetermined by the 0.2 % offset method.CClass BB, BC, BD hot-wrought; Class BB, BC cold-finished.A434/A434M 15
31、27.4 Test MethodTension tests shall be made in accordancewith Test Methods and Definitions A370 using the 0.2 % offsetmethod when determining yield strength.8. Permissible Variation of Dimensions8.1 Special StraightnessUnless otherwise specified, allmaterial shall be supplied to a straightness toler
32、ance of18 in.3.18 mm in any 5 ft 1.5 m, but may not exceed thefollowing:Maximum straightness 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
33、, the bars shall be free of injurious seams,laps, segregation, or other imperfections which, 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-finis
34、hed bars shall be given a surfacecoating of oil or other rust inhibitor to protect against 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
35、.11. Certification and Report of Testing11.1 When specified by the purchaser, a manufacturerscertification 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
36、. The report shall include the name of themanufacturer, ASTM designation number and year 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 t
37、ests when the requirementinvolves measured test values.12. Keywords12.1 alloy steel bars; 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 purchas
38、er inthe inquiry, contract, or order. Details of this supplementary requirement shall be 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 s
39、pecified by thepurchaser, shall be as agreed upon between the manufacturerand the purchaser.SUMMARY OF CHANGESCommittee A01 has identified the location of selected changes to this standard since the last issue(A43406(2012) that may impact the use of this standard. (Approved Nov. 1, 2015.)(1) Designa
40、tion was changed to dual.(2) Units statement in 1.3 was changed to a combined state-ment.(3) Table 1 was revised.A434/A434M 153ASTM 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
41、expressly advised that determination of the validity of any such patent rights, and the riskof 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 re
42、vised, either reapproved or withdrawn. Your comments are invited either for revision of this 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
43、may attend. If you feel that your comments have not received a fair hearing you shouldmake 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 S
44、tates. 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 Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 154
