1、Designation: A469/A469M 07 (Reapproved 2017)Standard Specification forVacuum-Treated Steel Forgings for Generator Rotors1This standard is issued under the fixed designation A469/A469M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision
2、, 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.1. Scope1.1 This specification covers vacuum-treated basic electricsteel forgings for generator rotors.1.2 Supplemen
3、tary requirements are provided, both in thisstandard and in Specification A788/A788M, for use whenadditional testing, inspection or processing is required by thepurchaser.1.3 The values stated in either inch-pound or SI (metric)units are to be regarded separately as standards. Within the textand tab
4、les, the SI units are shown in brackets. The values statedin each system are not exact equivalents; therefore, eachsystem must be used independent of the other. Combiningvalues from the two systems may result in nonconformancewith the specification.1.4 Unless the order specifies the applicable “M” s
5、pecifica-tion designation, the material shall be furnished to the inch-pound units.2. Referenced Documents2.1 ASTM Standards:2A275/A275M Practice for Magnetic Particle Examination ofSteel ForgingsA341/A341M Test Method for Direct Current MagneticProperties of Soft Magnetic Materials Using D-C Per-me
6、ameters and the Point by Point (Ballistic) Test MethodsA370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA418/A418M Practice for Ultrasonic Examination of Tur-bine and Generator Steel Rotor ForgingsA773/A773M Test Method for Direct Current MagneticProperties of Low Coercivity
7、Magnetic Materials UsingHysteresigraphsA788/A788M Specification for Steel Forgings, General Re-quirements3. Ordering Information and General Requirements3.1 In addition to the ordering information required bySpecification A788/A788M, the purchaser shall include withthe inquiry and order, a dimension
8、ed drawing showing themechanical test specimen locations, together with:3.1.1 Details of any required magnetic permeability tests(6.1).3.1.2 If the yield strength is to be determined at an offset of0.2%(Table 1), and number of tests (7.1.2 and 7.1.3).3.1.3 If vertical heat treatment is required (Sup
9、plementaryRequirement S3).3.1.4 If heat treatment by normalizing and tempering isrequired (4.2.2 and 4.2.3).3.1.5 If post rough machining stress relief may be omittedfor forgings that have been double tempered (4.2.2).3.1.6 Details for boring including dimensions, finish, timingand additional testin
10、g if required (8.3 and SupplementaryRequirement S1).3.1.7 Any applicable instructions regarding the requirednondestructive examinations (8).3.1.8 If vacuum arc remelted ingots are to be used, thepurchaser may require that footnote A to Table 2 be applicable.3.2 Material supplied to this specificatio
11、n shall conform tothe requirements of Specification A788/A788M, which out-lines additional ordering information, manufacturingrequirements, testing and retesting methods and procedures,marking, certification, production analysis variations, and ad-ditional supplementary requirements.3.3 Failure to c
12、omply with the applicable general require-ments of Specification A788/A788M constitutes nonconfor-mance with this specification.3.4 If the requirements of this specification are in conflictwith the requirements of Specification A788/A788M, therequirements of this specification shall prevail.4. Mater
13、ials and Manufacture4.1 The vacuum degassing requirements of SpecificationA788/A788M are mandatory.4.1.1 Other vacuum methods of degassing may be used ifthe supplier can demonstrate their adequacy to the satisfactionof the purchaser, but in this case, hydrogen testing perSupplementary Requirement S4
14、 is mandatory.1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.06 on Steel Forgings and Billets.Current edition approved March 15, 2017. Published March 2017. Originallyapproved in 1962
15、. Last previous edition approved in 2012 as A469/A469M 07(2012). DOI: 10.1520/A0469_A0469M-07R17.2For 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 Docum
16、ent Summary page onthe ASTM website.Copyright 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 Pr
17、inciples for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.14.2 Heat Treatment:4.2.1 Vertical heat treatment of the rotor forging ispreferred, and Supplementary Requirement S3 should bespecifie
18、d by the purchase order if this is required.4.2.2 The heat treatment for mechanical properties shallconsist of quenching and tempering, but normalizing andtempering is permissible with prior purchaser approval. Also,with prior purchaser approval, the post rough machining stressrelief in 4.2.3 may be
19、 omitted when double tempering is used,instead of a single temper, to complete this heat treatmentcycle.4.2.3 After heat treatment and the subsequent roughmachining, the forging shall be stress relieved at a minimumtemperature of 1050 F 565 C, unless otherwise specified bythe purchaser.4.3 Machining
20、:4.3.1 BoringThe manufacturer may bore the forging atany time prior to stress-relief anneal. (See SupplementaryRequirement S1).5. Chemical Composition5.1 Heat AnalysisThe heat analysis obtained from sam-pling in accordance with Specification A788/A788M shallcomply with Table 2.5.2 Product AnalysisTh
21、e manufacturer shall use the prod-uct analysis provision of Specification A788/A788M to obtaina product analysis from a forging representing each heat ormultiple heat.6. Magnetic Properties6.1 When specified in the ordering information, a perme-ability test shall be performed in accordance with the
22、latestissue of Test Method A341/A341M or Test Method A773/A773M.7. Mechanical Properties7.1 Tension Test:7.1.1 The steel shall conform to the requirements of Table 1.7.1.2 The number and locations of tension test specimensshall be as specified on the forging drawings furnished by thepurchaser.7.1.3
23、Tests for acceptance shall be made after heat treatmentof the forging for mechanical properties; however, the ultra-sonic examination requirements of 8.2.3 must be considered.The purchaser may require check tests after completion of allheating cycles including stress relieving in accordance with4.2.
24、3.TABLE 1 Tensile and Notch Toughness RequirementsGrade2345678Tensile strength, min, ksi 80 90 100 110 100 110 120MPa 550 620 690 760 690 760 825Yield strength,Amin, ksi 55 70 80 90 80 90 100MPa 380 485 550 620 550 620 690Elongation in 2 in. or 50 mm, min, % 20 20 17 15 18 17 16Reduction of area, mi
25、n, % 50 50 45 40 55 50 45FATT50, max, F 100 100 120 175 0 20 40FATT50, max, C 38 38 49 80 18 7 4Charpy absorbed energy at 70 5 F203C,30 30 25 15 60 50 40min, ftlbf J 40 40 34 20 80 68 55AYield strength at 0.02 % offset. Yield strength may also be specified at 0.2 % offset in which case 5000 psi 35 M
26、Pa shall be added to these values.TABLE 2 Chemical RequirementsElement Composition, %Grade 2 Grade 3 Grade 4 Grade 5 Grades 6, 7, 8Carbon, max 0.25 0.27 0.27 0.31 0.28Manganese, max 0.60 0.60 0.70 0.70 0.60Phosphorus, max 0.015 0.015 0.015 0.015 0.015Sulfur, max 0.015 0.015 0.015 0.015 0.015Silicon,
27、 maxA0.30 0.30 0.30 0.30 0.30Nickel 2.50 min 2.50 min 3.00 min 3.00 min 3.25 to 4.00Chromium 0.50 max 0.50 max 0.50 max 0.50 max 1.25 to 2.00Molybdenum 0.20 to 0.50 0.20 to 0.50 0.20 to 0.60 0.20 to 0.70 0.30 to 0.60Vanadium 0.03 min 0.03 min 0.03 min 0.05 to 0.15 0.05 to 0.15AntimonyB. . . . .AOpti
28、onal: For steel that is to be vacuum arc remelted a minimum silicon of 0.15 % may be specified.BReport for information on Grades 6, 7, and 8.A469/A469M 07 (2017)27.1.4 Testing shall be performed in accordance with thelatest issue of Test Methods and Definitions A370.7.1.5 The yield strength prescrib
29、ed in Table 1 shall bedetermined by the offset method at 0.02 % as described in TestMethods and Definitions A370.7.2 Impact Test:7.2.1 The material shall conform to the requirements fornotch toughness (both fracture appearance transition tempera-ture (FATT) and room temperature absorbed energy value
30、)prescribed in Table 1.7.2.2 Charpy V-notch specimens from surface radial testlocations shall be oriented with the root of the notch perpen-dicular to a radial axis of the forging and parallel to thelongitudinal axis of the forging. The notch shall be located asfar below the heat treated surface of
31、the forging as possiblewithout exceeding the dimensions specified for the test mate-rial. The actual distance from the outside diameter of theforging to the specimen notch shall be reported.8. Nondestructive Test Requirements8.1 General RequirementsThe forgings shall be free ofcracks, seams, laps, s
32、hrinkage, and other injurious imperfec-tions.8.2 Ultrasonic Inspection:8.2.1 An ultrasonic inspection shall be made at the forgingmanufacturers plant on the machined forgings. In making theultrasonic inspection, reference shall be made to the latest issueof Practice A418/A418M.8.2.2 Forgings having
33、recordable ultrasonic indicationsshall be referred to the purchaser and evaluated on the basis ofnature, frequency, and locations of indications both travelingand stationary. If the ultrasonic indications are consideredobjectionable, it shall be determined by conventional or mutu-ally acceptable ins
34、pection procedures whether the forging willbe rejected.8.2.3 Forgings shall be ultrasonically examined prior toremoval of the mid-body radial tension coupons.8.3 Internal InspectionBoring, when specified for bore-scope inspection, shall be as shown on the drawings furnishedby the purchaser. The draw
35、ings shall specify the nominaldimensions and surface finish of the hole. Magnetic particleexamination of the bore surface shall be performed in accor-dance with the latest issue of Practice A275/A275M. Themanufacturer shall report the results of the examination to thepurchaser and any further action
36、 shall be taken only aftermutual agreement.9. Retreatment9.1 If the results of the mechanical tests of any forging donot conform to the requirements specified, the manufacturermay retreat the forging one or more times, but not more thanthree additional times without approval of the purchaser, andret
37、ests shall be made in accordance with 7.1.2.9.2 If boring, specified under Supplementary RequirementsS1, was completed, the remaining portions of the bore coreshall be replaced in the bore during retreatment.10. Certification and Reports10.1 In addition to the requirements of Specification A788/A788
38、M, the product analysis results shall be reported.11. Packaging and Package Marking11.1 In addition to the marking requirements of Specifica-tion A788/A788M, axial bores, if any, shall be protected andsuitably plugged for shipment or storage.12. Keywords12.1 generator rotor forgings; steel forgings;
39、 vacuum-treated steel; vertical heat treatment; yield strength at 0.02 %offsetSUPPLEMENTARY REQUIREMENTSThe following supplementary requirements shall apply only when specified by the purchaser on theorder.S1. Bore Core TestsS1.1 The purchaser may require physical tests from the barcored from the lo
40、ngitudinal bore of the forging. These coretests will be for information only.S1.2 Specimens for bore core tests shall be cored from theforging after heat treatment for mechanical properties.S2. Method of ForgingS2.1 The purchaser may specify that hot working be per-formed on a press.S3. Vertical Hea
41、t TreatmentS3.1 Heat treatment for mechanical properties shall beperformed with the forging in the vertical position.S4. Hydrogen DeterminationS4.1 A hydrogen determination shall be made. The accept-able hydrogen limit as well as the stage in processing whensampling, the sample preparation procedure
42、 and the method ofanalysis shall be as agreed upon by manufacturer and pur-chaser.S5. Magnetic Particle ExaminationS5.1 A magnetic particle examination of the completeexterior and bore surfaces of the machined forging shall bemade at the forging manufacturers plant. The examinationshall be performed
43、 in accordance with the latest issue of TestMethod A275/A275M.S5.2 The purchaser shall establish the minimum length oflinear indications to be considered relevant.A469/A469M 07 (2017)3S5.3 Forgings with either cracks or relevant linear indica-tions are subject to rejection unless they can be removed
44、 to thepurchasers satisfaction.S6. Silicon ContentS6.1 The maximum silicon content shall be 0.10 %.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 deter
45、mination 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 revised, either reapproved or
46、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 may attend. If you feel that
47、 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 States. Individual reprints (
48、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:/ 07 (2017)4
