1、Designation: A295/A295M 09Standard Specification forHigh-Carbon Anti-Friction Bearing Steel1This standard is issued under the fixed designation A295/A295M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last revision.
2、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 Department of Defense.1. Scope*1.1 This specification covers high-carbon bearing-quali
3、tysteel to be used in the manufacture of anti-friction bearings.1.2 Supplementary requirements of an optional nature areprovided and when desired shall be so stated in the order.1.3 The values stated in either inch-pound units or SI unitsare to be regarded separately as standard. The values stated i
4、neach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other.2. Referenced Documents2.1 ASTM Standards:2A29/A29M Specification for Steel Bars, Carbon and Alloy,Hot-Wrought, General Requirements forA370 Test Methods and Definitions for Mechanical Testingof
5、 Steel ProductsA751 Test Methods, Practices, and Terminology for Chemi-cal Analysis of Steel ProductsA892 Guide for Defining and Rating the Microstructure ofHigh Carbon Bearing SteelsE45 Test Methods for Determining the Inclusion Content ofSteelE112 Test Methods for Determining Average Grain SizeE38
6、1 Method of Macroetch Testing Steel Bars, Billets,Blooms, and ForgingsE1019 Test Methods for Determination of Carbon, Sulfur,Nitrogen, and Oxygen in Steel, Iron, Nickel, and CobaltAlloys by Various Combustion and Fusion TechniquesE1077 Test Methods for Estimating the Depth of Decarbur-ization of Ste
7、el Specimens2.2 Other Document:ISO 683, Part 17 Ball and Roller Bearing Steels33. Ordering Information3.1 Orders for material under this specification shouldinclude the following information:3.1.1 Quantity,3.1.2 Grade identification,3.1.3 Specification designation and year of issue,3.1.4 Dimensions,
8、 and3.1.5 Supplementary requirements, if included.4. Process4.1 The steel shall be made by a process that is capable ofproviding a high quality product meeting the requirements ofthis specification.5. Chemical Composition and Analysis5.1 Typical examples of chemical compositions are shownin Table 1.
9、 Other compositions may be specified.5.2 An analysis of each heat of steel shall be made by thesteel manufacturer in accordance with Test Methods, Practices,and Terminology A751. The chemical composition thus deter-mined shall conform to the requirements specified in Table 1for the ordered grade or
10、to other requirements agreed uponbetween manufacturer and purchaser.5.3 Product analysis may be made by the purchaser inaccordance with Test Methods, Practices, and TerminologyA751. Permissible variations in product analysis shall be inaccordance with Specification A29/A29M.6. Sizes, Shapes, and Dim
11、ensional Tolerances6.1 The physical size and shape of the material shall beagreed upon between manufacturer and purchaser.6.2 Dimensional tolerances for hot-rolled or hot-rolled andannealed bars, in straight lengths or coils, and cold-finishedbars 0.500 in. 12.5 mm and larger in diameter furnished u
12、nderthis specification shall conform to the requirements specified inthe latest edition of Specification A29/A29M.1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.28 on Bearing Steels.C
13、urrent edition approved Oct. 1, 2009. Published November 2009. Originallyapproved in 1946. Last previous edition approved in 2005 as A295/A295M 05.DOI: 10.1520/A0295_A0295M-09.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. Fo
14、r Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from International Organization for Standardization (ISO), 1 rue deVaremb, Case postale 56, CH-1211, Geneva 20, Switzerland.1*A Summary of Changes section appears at the end
15、of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.3 Dimensional tolerances for cold-finished coils for balland roller material shall be as shown in Table 2.6.4 Coil tolerances also apply to cold-finished straightlengt
16、hs under 0.500 in. 12.5 mm in diameter.7. Quality Tests7.1 The supplier shall be held responsible for the quality ofthe material furnished and shall make the necessary tests toensure this quality. The supplier shall be required to reportresults of the micro-inclusion rating tests detailed below.Qual
17、ity tests shown in 7.2 and 7.3 are based upon proceduresestablished in Test Methods E45.7.2 SamplingSamples taken in accordance with the fol-lowing paragraphs shall be obtained from 4 by 4 in. 100 by100 mm rolled billets or forged sections. Tests may be madeon smaller or larger sections by agreement
18、 between manufac-turer and purchaser. A minimum 3 to 1 reduction of rolledbillets or forged sections is required for strand cast products.7.2.1 For top poured products, a minimum of six samplesrepresenting the top and bottom of the first, middle, and lastusable ingots shall be examined.7.2.2 For bot
19、tom poured products, a minimum of sixsamples shall be examined and they shall represent the top andbottom of three ingots. One ingot shall be taken at randomfrom the first usable plate poured, one ingot, at random, fromthe usable plate poured nearest to the middle of the heat, andone ingot, at rando
20、m, from the last usable plate poured. Whentwo usable plates constitute a heat, two of the sample ingotsshall be selected from the second usable plate poured. Where asingle usable plate constitutes a heat, any three random ingotsmay be selected. Other methods of sampling shall be as agreedupon betwee
21、n manufacturer and purchaser.7.2.3 For strand cast products, a minimum of six samplesrepresenting the first, middle, and last portion of the heat castshall be examined. At least one sample shall be taken fromeach strand.7.3 Inclusion RatingThe specimens shall be38 by34 in.10 by 20 mm and shall be ta
22、ken from an area halfwaybetween the center and outside of the billet. The polished faceshall be longitudinal to the direction of rolling. The scale usedfor rating the specimens shall be the Jernkontoret chartdescribed in Test Methods E45, Plate I-r. Fields with sizes ornumbers of all types of inclus
23、ions intermediate betweenconfigurations shown on the chart shall be classified as thelesser of the rating number. The worst field of each inclusiontype from each specimen shall be recorded as the rating for thespecimen. Two thirds of all specimens and at least one fromeach ingot tested, or from the
24、first, middle, and last portion ofthe strands tested, as well as the average of all specimens, shallnot exceed the rating specified in Table 3. If specificallyordered and certified to Supplementary Requirement S4, TypeA inclusion ratings shall not exceed 3.0 thin and 2.0 heavy. SeeS4.1.8. Grain Size
25、8.1 The steels covered by this specification shall have thecapability of showing a fine fracture grain size (approximatelyASTM No. 8 in accordance with Test Methods E112) whenquenched from normal austenitizing temperatures not exceed-ing 1550F 840C.9. Decarburization and Surface Imperfections9.1 Dec
26、arburization and surface imperfections shall notexceed the limits specified in Tables 4 and 5. Decarburizationshall be measured using the microscopical methods describedin Test Methods E1077.10. Microstructure10.1 When annealing is specified in the order, the structureshall be rated and reported in
27、accordance with Guide A892 asfollows:10.1.1 Carbide Size (CS)As the appropriate carbide sizeis dependent on application, the limits shall be as agreed uponbetween manufacturer and purchaser.10.1.2 Carbide Network (CN)As the network is influ-enced by section size, the limits shall be as agreed uponbe
28、tween manufacturer and purchaser.10.1.3 Lamellar Content (LC)52100 steels shall have alamellar content not to exceed LC1. Lamellar content of othercompositions shall be as agreed upon between manufacturerand purchaser.TABLE 1 CompositionA,BName C Mn P (max) S (max) Si Cr Ni (max) Mo Cu (max) O (max)
29、CAl (max)D52100E0.93-1.05 0.25-0.45 0.025 0.015 0.15-0.35 1.35-1.60 0.25 0.10 (max) 0.30 0.0015 0.0505195 0.90-1.03 0.75-1.00 0.025 0.015 0.15-0.35 0.70-0.90 0.25 0.10 (max) 0.30 0.0015 0.0505090M 0.89-1.01 0.50-0.80 0.025 0.015 0.15-0.35 0.40-0.60 0.25 0.08-0.15 0.30 0.0015 0.0501070M 0.65-0.75 0.8
30、0-1.10 0.025 0.015 0.15-0.35 0.20 (max) 0.25 0.10 (max) 0.30 0.0015 0.0505160 0.56-0.64 0.75-1.00 0.025 0.015 0.15-0.35 0.70-0.90 0.25 0.10 (max) 0.30 0.0015 0.050AElements not quoted shall not be intentionally added to the steel without the agreement of the purchaser.BIntentional additions of calci
31、um or calcium alloys for deoxidation or inclusion shape control are not permitted unless specifically approved by the purchaser.COxygen content applies to product analysis and shall be determined in accordance with Test Methods E1019.DTotal aluminum content.ESpecified element ranges meet the require
32、ments of ISO 683, Part 17, Table 3, NO. B1, 100CR6.TABLE 2 Dimensional Tolerances for Cold-Finished CoilsSize, in. mm Total Tolerance, in. mmThrough 0.096 2.50 0.002 0.05Over 0.096 2.50 to 0.270 7.00, incl 0.003 0.08Over 0.270 7.00 to 0.750 19.0, incl 0.004 0.10TABLE 3 Inclusion RatingRating UnitsTh
33、in Series Heavy SeriesA212 A112B2 B1C12 C12D1 D1A295/A295M 09210.2 The material shall be free from excessive carbidesegregation.11. Hardness11.1 When annealing is specified in the order, the steel shallhave a completely spheroidized microstructure and a hardnessas specified in Table 6.11.2 Small siz
34、es where Rockwell B scale hardness readingsare impractical shall have a maximum tensile strength of110 000 psi (760 MPa).11.3 Hardness and tensile tests shall be in accordance withtest methods described in Test Methods and Definitions A370.12. Inspection12.1 The manufacturer shall afford the purchas
35、ers inspectorall reasonable facilities necessary to satisfy him that thematerial is being produced and furnished in accordance withthis specification. Mill inspection by the purchaser shall notinterfere unnecessarily with the manufacturers operations. Alltests and inspections shall be made at the pl
36、ace of manufacture,unless otherwise agreed to.13. Certification and Reports13.1 Upon request of the purchaser in the contract or order,a manufacturers certification that the material was manufac-tured and tested in accordance with this specification, togetherwith a report of the test results, shall
37、be furnished at the timeof shipment. Special requirements agreed to at the time ofpurchase shall be noted on the certification.SUPPLEMENTARY REQUIREMENTSOne or more of the supplementary requirements described below apply when included in thepurchasers order or contract. When so included, a supplemen
38、tary 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 not negate any of therequirements in the body of the specification.TABLE 4 Decarburiz
39、ation and Surface Imperfections for Coils and Bars for Balls and RollersSize, in. mm Decarburization or Surface Imperfections per Side, max, in. mmHot-Rolled or Hot-Rolled Annealed Cold-Finished AnnealedThrough 0.250 6.50 0.005 0.13 0.003 0.08Over 0.250 6.50 to 0.500 12.5, incl 0.006 0.15 0.004 0.10
40、Over 0.500 12.5 to 0.750 19.0, incl 0.008 0.20 0.006 0.15Over 0.750 19.0 to 1.000 25.0, incl 0.010 0.25 0.008 0.20TABLE 5 Decarburization and Surface Imperfections for Bars and TubesSize, in. mm Decarburization or Surface Imperfections per Side, max, in. mmHot-Rolled Bars Hot-Rolled Annealed Cold-Fi
41、nished AnnealedBars Tubes Bars TubesThrough 1.000 25.0 0.012 0.30 0.015 0.38 0.012 0.30 0.012 0.30 0.010 0.25Over 1.000 25.0 to 2.000 50.0, incl 0.017 0.43 0.022 0.56 0.020 0.51 0.015 0.38 0.014 0.36Over 2.000 50.0 to 3.000 75.0, incl 0.025 0.64 0.030 0.76 0.030 0.76 0.025 0.64 0.019 0.48Over 3.000
42、75.0 to 4.000 100.0, incl 0.035 0.89 0.045 1.14 0.035 0.89 0.024 0.61Over 4.000 100.0 to 5.000 125.0, incl 0.055 1.40 0.065 1.65 0.040 1.02 0.028 0.71TABLE 6 Maximum Hardness for Annealed MaterialProduct Condition Maximum HardnessBrinell Rockwell BCoils hot-rolled, annealed . . . 92Bars and tubes ho
43、t-rolled annealed 207 . . .Coils annealed, cold-drawn (stress-relieved). 92Coils, bars, and annealed, cold-drawnA248 . . .tubesTubes annealed, cold-rocked 331 . . .ACold-swaged material is not included.A295/A295M 093S1. Titanium ContentS1.1 The purchaser may specify that the analysis of titaniumbe p
44、rovided by agreement with the steel manufacturer.S2. “SAM” Inclusion Rating SystemS2.1 The purchaser may specify that the “SAM” inclusionrating system described in Method E of Test Methods E45 beused in addition to the micro-inclusion rating system describedin 7.3.S2.2 SamplingSee 7.2.S2.3 LimitsThe
45、 “SAM” rating for B-type inclusions shallnot exceed fifteen. The “SAM” rating for D-type inclusionsshall not exceed ten.S3. Magnetic Particle MethodS3.1 The purchaser may specify that the magnetic particlemethod described below be used in addition to the micro-inclusion rating system described in 7.
46、3. The magnetic particlemethod measures bearing steel cleanliness by evaluating thetotal length of macro-inclusions for a stated area or per unitarea. Results are expressed in millimeters per square metre.S3.2 SamplingSee 7.2.S3.3 Test specimens shall be straight cylinder quarter sec-tion samples pr
47、epared and examined in accordance with themagnetic particle method of Test Methods E45.S3.4 For purposes of calculation, an inclusion length shallbe taken as the mean length of the length bracket into which itfalls; that is, an inclusion in the 1.6 to 3.2 mm bracket shall betaken as being 2.4 mm in
48、length. The sum of all lengths foreach specimen shall be determined and expressed as totallength per area inspected. The average total length per areainspected of all six specimens shall not exceed 200 mm/m2.S4. Sulfur Requirement for MachinabilityS4.1 A sulfur content in the range of 0.0150.030 % m
49、ay bespecified for improved machinability.S4.2 When this supplementary requirement is specified, thesulfide (Type A) ratings of 7.3 shall be 3.0 thin and 2.0 heavy.S4.3 The manufacturers certification shall state that mate-rial was produced to this supplementary requirement whenapplicable.S5. Sample Reduction RatioS5.1 For the sampling described in 7.2, the purchaser mayspecify that the reduction ratio from as-cast sect
