1、Designation: A434 06 (Reapproved 2012)Standard Specification forSteel Bars, Alloy, Hot-Wrought or Cold-Finished, Quenchedand Tempered1This standard is issued under the fixed designation A434; the number immediately following the designation indicates the year oforiginal adoption or, in the case of r
2、evision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript 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. Scope1.1 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 inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.2. Referenced Documents2.1 ASTM Standards:2A29
5、/A29M Specification for Steel Bars, Carbon and Alloy,Hot-Wrought, General Requirements forA108 Specification for Steel Bar, Carbon and Alloy, Cold-FinishedA370 Test Methods and Definitions for Mechanical Testingof Steel ProductsE112 Test Methods for Determining Average Grain Size3. Ordering Informat
6、ion3.1 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),3.1.4 Dimensions, including length (if hot-wrought bars arefor cold
7、finishing, the cold-finished size should also be speci-fied),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 Supplementary Requirements or Special Require-ments, if required, and3.1
8、.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 3 10 ft,ASTM A434 dated _, Grade 4140, Class BB, Test Report Required,Motor Shafts.4. Materials and Manufacture4.1 Melting PracticeThe steel shall be made by one or
9、more 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 electroslag remelting or vacuum arcremelting. Where secondary melting is employed, the heatshall
10、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 bars shall, immedi-ately after rolling, be allowed to cool to a temperature belowthe critical
11、range under suitable conditions to prevent injury bytoo rapid cooling.4.4 ConditionBars shall be furnished in one of the fol-lowing conditions, as specified by the purchaser. Generally,size limits for various methods of processing round bars are:Hot-wrought or hot-wrought descaled912 in. (241.3 mm),
12、 maxCold-drawn18 to 4 in. (3.2 to 102 mm), inclCold-drawn, ground, and pol-ished18 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 229 mm),incl4.5 Heat Treatment:4.5.1 Heat treatment shall include quenching and temper
13、ingfor all classes of material. The material shall be uniformlyheated to the austenitizing temperature, soaked for a sufficient1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.15 on Bar
14、s.Current edition approved March 1, 2012. Published April 2012. Originallyapproved in 1959. Last previous edition approved in 2006 as A434 06. DOI:10.1520/A0434-06R12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual
15、Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.length of time to produce the desired structure (a lot thusheated being known a
16、s 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 tempering (a lot thusreheated being known as a “tempering charge”), and allowed tocool uniformly. The
17、temperature selected for tempering shallbe not less than 800F (427C).4.5.2 Material cold drawn after heat treatment shall be stressrelieved, 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-t
18、reated 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 in the stress-relieving operation, thebars may be restraightened without further stress-relieving,pr
19、ovided 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 Table 2 of Specification A29/A29M, or to such othercompositions as may be specified using the ranges a
20、nd 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 specified is not capableof developing the mechanical properties, the manufacturershall notify the pur
21、chaser 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 RequirementThe bars shall have an austenitic grainsize of 5 and finer. The grain structure shall be consideredsa
22、tisfactory if 70 % is within the specified size limits.6.2 SpecimensGrain size specimens shall be taken inaccordance with Test Methods E112.6.3 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 Meth
23、od of Test Methods E112.7. 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 taken longitudinally after finalprocessing.7.2.2 Test specimens shall b
24、e 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 charge is represented, one tension test shall be madefrom each quenching c
25、harge. 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.7.4 Test MethodTension tests shall be made in accordancewith Test Met
26、hods and Definitions A370 using the 0.2 % offsetmethod when determining yield strength.TABLE 1 Tensile PropertiesNOTEThe mechanical properties of hot-wrought bars ordered for cold finishing, shall be governed by the cold-finished size.Class Diameter, in. (mm) Yield Strength, min,ksi (MPa)ATensile St
27、rength,min, ksi (MPa)Elongationin 2 in. or50 mm,min, %Reductionof Area,min, %SAE or AISI Repre-sentative GradeTypesB112 (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)
28、 20 50Over 4 to 7 (114 to 178), incl 75 (520) 95 (660) 20 50Over 7 to 912 (178 to 241.3), 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)
29、 115 (790) 16 45Over 4 to 7 (114 to 178), incl 85 (590) 110 (760) 16 45J3100, 4100Over 7 to 912 (178 to 241.3), 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.
30、5 to 114), incl 110 (760) 140 (960) 14 35Over 4 to 7 (114 to 178), incl 105 (720) 135 (930) 14 35Over 7 to 912 (178 to 241.3), 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.BDeterm
31、ined by the 0.2 % offset method.CClass BB, BC, BD hot-wrought; Class BB, BC cold-finished.A434 06 (2012)28. 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
32、not exceed thefollowing:Maximum straightness deviation, in. 5 1/8 3length 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,
33、 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-finished bars shall be given a surfacecoating of oil o
34、r 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 A108.11. Certification and Report of Testing11.1 When
35、 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. The report shall include the name of themanufac
36、turer, ASTM designation number and yeardate 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 va
37、lues.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 purchaser inthe inquiry, contract, or order. Details of t
38、his 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 specified by thepurchaser, shall be as agreed upon
39、between the manufacturerand the purchaser.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 t
40、he 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 revised, either reapproved or withdrawn. Your comments are invited either for revision
41、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 may attend. If you feel that your comments have not received a fair hearing you shoul
42、dmake 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/).A434 06 (2012)3
