1、Designation: A485 09A485 14Standard Specification forHigh Hardenability Antifriction Bearing Steel1This standard is issued under the fixed designation A485; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、 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 U.S. Department of Defense.1. Scope*1.1 This specification covers high hardenability
3、modifications of high-carbon bearing quality steel to be used in the manufactureof antifriction bearings.1.2 Supplementary requirements of an optional nature are provided and when desired shall be so stated in the order.1.3 The values stated in inch-pound units are to be regarded as standard. The va
4、lues given in parentheses are mathematicalconversions to SI units that are provided for information only and are not considered standard.2. Referenced Documents2.1 ASTM Standards:2A29/A29M Specification for General Requirements for Steel Bars, Carbon and Alloy, Hot-WroughtA255 Test Methods for Deter
5、mining Hardenability of SteelA751 Test Methods, Practices, and Terminology for Chemical Analysis of Steel ProductsE45 Test Methods for Determining the Inclusion Content of SteelE381 Method of Macroetch Testing Steel Bars, Billets, Blooms, and ForgingsE1019 Test Methods for Determination of Carbon, S
6、ulfur, Nitrogen, and Oxygen in Steel, Iron, Nickel, and Cobalt Alloys byVarious Combustion and Fusion TechniquesE1077 Test Methods for Estimating the Depth of Decarburization of Steel Specimens2.2 Other Standards:SAE J148a Grain Size Determination of Steel3ISO 683 Part 17: Ball and Roller Bearing St
7、eels43. Ordering Information3.1 Orders for material under this specification should include the following information:3.1.1 Quantity (weight or number of pieces),3.1.2 Grade identification,3.1.3 ASTM designation and year of issue,3.1.4 Dimensions,3.1.5 Supplementary requirements, if included.4. Proc
8、ess4.1 The steel shall be made by a process that is capable of providing a high quality product meeting the requirements of thisspecification.1 This specification is under the jurisdiction ofASTM Committee A01 on Steel, Stainless Steel and RelatedAlloys, and is the direct responsibility of Subcommit
9、tee A01.28on Bearing Steels.Current edition approved Oct. 1, 2009Oct. 1, 2014. Published November 2009November 2014. Originally approved in 1963. Last previous edition approved in 20032009as A485 03.A485 09. DOI: 10.1520/A0485-09.10.1520/A0485-14.2 For referencedASTM standards, visit theASTM website
10、, 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.3 Available from The Engineering Society for Advanced Mobility of Land, Sea, Air and Space, 400 Commonwealth Drive
11、, Warrendale, PA 15096-001.SAE International(SAE), 400 Commonwealth Dr., Warrendale, PA 15096-0001, http:/www.sae.org.4 Available from the International Organization for Standardization (ISO), 1, rue de Varemb, Case postale 56, CH-1211, Genve 20, Switzerland. ch. de la Voie-Creuse,CP 56, CH-1211 Gen
12、eva 20, Switzerland, http:/www.iso.org.This document 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
13、recommends that users consult prior editions as appropriate. 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 Bo
14、x C700, West Conshohocken, PA 19428-2959. United States15. Chemical Composition and Analysis5.1 Typical examples of chemical compositions are shown in Table 1. Other compositions may be specified.5.2 An analysis of each heat of steel shall be made by the steel manufacturer in accordance with Test Me
15、thods, Practices, andTerminology A751. The chemical composition thus determined shall conform to the requirements specified in Table 1 for theordered grade or to other requirements agreed upon between manufacturer and purchaser.5.3 Product analysis may be made by the purchaser in accordance with Tes
16、t Methods, Practices, and Terminology A751.Permissible variations in product analysis shall be in accordance with Specification A29/A29M.6. Sizes, Shapes, and Dimensional Tolerances6.1 The physical size and shape of the material shall be agreed upon between manufacturer and purchaser.6.2 Dimensional
17、 tolerances for hot-rolled or hot-rolled and annealed bars, in straight lengths or coils, and cold-finished barsfurnished under this specification shall conform to the requirements specified in the latest edition of Specification A29/A29M.7. Quality Tests7.1 The supplier shall be held responsible fo
18、r the quality of the material furnished and shall make the necessary tests to ensurethis quality. The supplier shall be required to report on the results of the micro-inclusion rating tests detailed below. Quality testsshown in 7.1 through 7.3 are based upon procedures established in Test Methods E4
19、5.7.2 SamplingSamples taken in accordance with the following paragraphs shall be obtained from 4 by 4 in. (102 by 102 mm)rolled billets or forged sections. Tests may be made on smaller or larger sections by agreement with the purchaser. A minimumof 3 to 1 reduction of rolled billets or forged sectio
20、ns is required for strand cast products.7.2.1 For top poured products, a minimum of six samples representing the top and bottom of the first, middle and last usableingots shall be examined.7.2.2 For bottom poured products, a minimum of six samples shall be taken from semi-finished or finished produc
21、t representingthe top and bottom of three ingots. One ingot shall be taken at random from the first usable plate poured, one ingot at random fromthe usable plate poured nearest to the middle of the heat, and one ingot at random from the last usable plate poured. When a heatis constituted by two usab
22、le plates, two of the sample ingots shall be selected from the second usable plate poured. When a heatconsists of a single usable plate, any three random ingots may be selected. Other methods of sampling shall be as agreed uponbetween manufacturer and purchaser.7.2.3 For strand cast products, a mini
23、mum of six samples representing the first, middle, and last portion of the heat cast shallbe examined. At least one sample shall be taken from each strand.7.3 Inclusion RatingSpecimens approximately 38 by 34 in. (9.5 by 19.1 mm) shall be taken from an area halfway between thecenter and outside of th
24、e billet. The polished face shall be longitudinal to the direction of rolling. The scale used for rating thespecimens shall be the chart described in Test Methods E45, Method A, Plate I-r.I-A. Inclusion fields with sizes or numbersintermediate between configurations shown on the chart shall be class
25、ified as the lesser of the rating number. The worst field ofeach inclusion type from each specimen shall be recorded as the rating for the specimen. Two thirds of all specimens and at leastone from each ingot tested, or from the first, middle and last portion of the strands tested as well as the ave
26、rage of all specimens,shall not exceed the rating specified in Table 2.8. Grain Size8.1 The steels covered by this specification shall have the capability of showing fine fracture grain size (approximately ASTMNo. 8) (SAE J418a) when quenched from normal austenizing temperatures not exceeding 1550F
27、(843C).TABLE 1 Chemical CompositionA,BNumberC Name C Mn P (max) S (max) Si Cr Ni (max) Ti (max) Cu (max) Mo O (max)D Al (max)1 Grade 1 0.901.05 0.901.20 0.025 0.015 0.450.75 0.901.20 0.25 0.0050 0.30 0.10 (max) 0.0015 0.0502 Grade 2 0.851.00 1.401.70 0.025 0.015 0.500.80 1.401.80 0.25 0.0050 0.30 0.
28、10 (max) 0.0015 0.0503 Grade 3 0.951.10 0.650.90 0.025 0.015 0.150.35 1.101.50 0.25 0.0050 0.30 0.200.30 0.0015 0.0504 Grade 4 0.951.10 1.051.35 0.025 0.015 0.150.35 1.101.50 0.25 0.0050 0.30 0.450.60 0.0015 0.050B2 100CrMnSi44 0.931.05 0.901.20 0.025 0.015 0.450.75 0.901.20 . . . E 0.30 0.10 (max)
29、0.0015 0.050B3 100CrMnSi64 0.931.05 1.001.20 0.025 0.015 0.450.75 1.401.65 . . . E 0.30 0.10 (max) 0.0015 0.050B4 100CrMnSi66 0.931.05 1.401.70 0.025 0.015 0.450.75 1.401.65 . . . E 0.30 0.10 (max) 0.0015 0.050B5 100CrMo7 0.931.05 0.250.45 0.025 0.015 0.150.35 1.651.95 . . . E 0.30 0.150.30 0.0015 0
30、.050B6 100CrMo73 0.931.05 0.600.80 0.025 0.015 0.150.35 1.651.95 . . . E 0.30 0.200.35 0.0015 0.050B7 100CrMo74 0.931.05 0.600.80 0.025 0.015 0.150.35 1.651.95 . . . E 0.30 0.400.50 0.0015 0.050B8 100CrMnMoSi846 0.931.05 0.801.10 0.025 0.015 0.400.60 1.802.05 . . . E 0.30 0.500.60 0.0015 0.050A Elem
31、ents not quoted shall not be intentionally added to the steel without the agreement of the purchaser.B Intentional additions of calcium or calcium alloys for deoxidation or inclusion shape control are not permitted unless specifically approved by the purchaser.C Steels B2 through B8 meet the require
32、ments of ISO 683, Part 17, Second Edition, Table 3.D Oxygen content applies to product analysis and shall be determined in accordance with Test Methods E1019.E A maximum titanium content may be agreed upon at the time of inquiry and order.A485 1429. Hardenability9.1 Each heat of the grades in Table
33、3 shall be tested for hardenability. Normalizing followed by spheroidize annealing shallprecede heating for end quenching. In heating for end quenching, the test specimens shall be held for a minimum of 30 min at 15006 8F (815 6 4.5C). End-quench procedure shall be in accordance with Test Methods A2
34、55. The “J” values for hardenabilityas shown in Table 3 shall apply.10. Decarburization and Surface Imperfections10.1 Decarburization and surface imperfections shall not exceed the limits specified in Table 4. Decarburization shall bemeasured using the microscopical methods described in Test Methods
35、 E1077.11. Microstructure and Hardness11.1 The material shall be free of excessive carbide segregation.11.2 When annealing is specified in the order, the steel shall have a microstructure completely spheroidized, or as agreed upon,and the maximum hardness as specified in Table 5.12. Inspection12.1 T
36、he manufacturer shall afford the purchasers inspector all reasonable facilities necessary to satisfy him that the materialis being produced and furnished in accordance with this specification. Mill inspection by the purchaser shall not interfereunnecessarily with the manufacturers operations. All te
37、sts and inspections shall be made at the place of manufacture, unlessotherwise agreed to.13. Certification and Reports13.1 Upon request of the purchaser in the contract or order, a manufacturers certification that the material was manufacturedand tested in accordance with this specification together
38、 with a report of the test results shall be furnished at the time of shipment.Special requirements agreed to at the time of purchase must be noted on the certification.TABLE 2 Inclusion RatingRating UnitsThin Series Heavy SeriesA212 A112B2 B1C12 C12D1 D1TABLE 2 Inclusion RatingRating UnitsThin Serie
39、s Heavy SeriesA2.5 A1.5B2.0 B1.0C0.5 C0.5D1.0 D1.0TABLE 3 Hardenability ValuesRockwell CMinimum Rockwell C Values at Sixteenth of InchGrade 10 20 281 46 . . . . . .2 . . . 52 323 46 . . . . . .4 . . . 52 35A485 143SUPPLEMENTARY REQUIREMENTSOne or more of the supplementary requirements described belo
40、w apply when included inpurchasers order or contract. When so included, a supplementary requirement shall have the sameforce as if it were in the body of the specification. Supplementary requirements details not fullydescribed shall be agreed upon between the purchaser and the supplier, but shall no
41、t negate any of therequirements in the body of the specification.S1. “SAM” Inclusion Rating SystemS1.1 The purchaser may specify that the “SAM” inclusion rating method, described in Method E of Test Methods E45, be usedin addition to the micro-inclusion rating method described in 7.3.S1.2 SamplingSe
42、e Section 7.S1.3 LimitsThe “SAM” rating for Type B inclusions shall not exceed 15. The “SAM” rating for Type D inclusions shall notexceed 10.S2. Magnetic Particle MethodS2.1 The purchaser may specify that the magnetic particles method described below be used in addition to the micro-inclusionrating
43、system described in 7.3. The magnetic particle method measures bearing steel cleanliness by evaluating the total length ofmacro-inclusions for a stated area or per unit area. Results are commonly expressed in mm/m2.S2.2 SamplingSee 7.2.S2.3 Test specimens shall be straight cylinder quarter section s
44、amples prepared and examined in accordance with the magneticparticle method of Test Methods E45.S2.4 For purposes of calculation, an inclusion length shall be taken as the mean length of the length bracket in which it falls;that is, an inclusion in the 116 to 18 in. bracket shall be taken as being 3
45、32 in length. The sum of all lengths for each specimen shallbe determined and expressed as total length per area inspected. The average total length per area inspected of all six specimensshall not exceed 200 mm/m2 (or equivalent).TABLE 4 Decarburization and Surface Imperfections for Bars and TubesM
46、aximum Decarburization or Surface Imperfections per Side, in. (mm)Size, in. (mm) Hot-Rolled Bars Hot-Rolled Annealed Cold-Finished AnnealedBars Tubes Bars TubesOver 1.000 (25.4) to 2.000 (50.8),incl0.017 (0.43) 0.022 (0.56) 0.020 (0.51) 0.017 (0.43) 0.014 (0.36)Over 2.000 (50.8) to 3.000 (76.2),incl
47、0.025 (0.64) 0.030 (0.76) 0.030 (0.76) 0.025 (0.64) 0.019 (0.48)Over 3.000 (76.2) to 4.000 (101.6),incl0.035 (0.89) 0.045 (1.14) 0.035 (0.89) . . . 0.024 (0.61)Over 4.000 (101.6) to 5.000(127.0), incl0.055 (1.40) 0.065 (1.65) 0.040 (1.02) . . . 0.028 (0.71)TABLE 5 Hardness Limits for Annealed Materi
48、alProduct Condition Maximum HardnessBrinell RockwellCoils hot-rolled, annealed . . . B97Bars and tubes hot-rolled, annealed 217 . . .Coils annealed, colddrawn (stress re-lieved). . . B92Coils, bars, and tubes annealed, colddrawnA260 . . .A Cold swaged material is not included.A485 144S3. Sulfur Requ
49、irements for MachinabilityS3.1 The sulfur content shall be 0.0150.030 %.S3.2 The sulfide (type A) rating units in Table 2 shall be 3.0 thin and 2.0 heavy.S3.3 The manufacturers certification shall state that material was produced to this supplementary requirement when applicable.S4. Calculated HardenabilityS4.1 A calculated hardenability shall be used in lieu of the requirements in Section 9. The method used shall be agreed uponbetween the purchaser and the steel supplier at