1、Designation: A 295/A 295M 05Standard Specification forHigh-Carbon Anti-Friction Bearing Steel1This standard is issued under the fixed designationA 295/A 295M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last revisio
2、n. A number in parentheses indicates the year of last reapproval.A superscript epsilon (e) 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-q
3、ualitysteel 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 stat
4、ed ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other.2. Referenced Documents2.1 ASTM Standards:2A 29/A 29M Specification for Steel Bars, Carbon andAlloy,Hot-Wrought, General Requirements forA 370 Test Methods and Definitions for Mechanical Tes
5、tingof Steel ProductsA 751 Test Methods, Practices, and Terminology forChemical Analysis of Steel ProductsA 892 Guide for Defining and Rating the Microstructure ofHigh Carbon Bearing SteelsE45 Test Methods for Determining the Inclusion Contentof SteelE112 Test Methods for Determining Average Grain S
6、izeE 381 Method of Macroetch Testing Steel Bars, Billets,Blooms, and ForgingsE 1019 Test Methods for Determination of Carbon, Sulfur,Nitrogen, and Oxygen in Steel and in Iron, Nickel, andCobalt AlloysE 1077 Test Methods for Estimating the Depth of Decar-burization of Steel Specimens2.2 Other Documen
7、t: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, and3.1.5 Supplementary requi
8、rements, 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. Other compositions may be sp
9、ecified.5.2 An analysis of each heat of steel shall be made by thesteel manufacturer in accordance with Test Methods A 751.The chemical composition thus determined shall conform tothe requirements specified in Table 1 for the ordered grade orto other requirements agreed upon between manufacturer and
10、purchaser.5.3 Product analysis may be made by the purchaser inaccordance with Test Methods A 751. Permissible variations inproduct analysis shall be in accordance with SpecificationA 29/A 29M.6. Sizes, Shapes, and Dimensional Tolerances6.1 The physical size and shape of the material shall beagreed u
11、pon 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 underthis specification shall conform to the requirements specified inthe latest edi
12、tion of Specification A 29/A 29M.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.Current edition approved March 1, 2005. Published April 2005. Originallyapproved
13、in 1946. Last previous edition approved in 1998 as A 295 98.2For 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 Document Summary page onthe ASTM website.3
14、Available 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 of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,
15、 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 straightlengths under 0.500 in. 12.5 mm in diameter.7. Quality Tests7.1 The supplier shall be held responsible for the quality of
16、the material furnished and shall make the necessary tests toensure this quality. The supplier shall be required to reportresults of the macroetch and micro-inclusion rating testsdetailed below. Quality tests shown in 7.2-7.4 are based uponprocedures established in Test Methods E45.7.2 SamplingSample
17、s 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 between manufac-turer and purchaser. A minimum 3 to 1 reduction of rolledbillets or forged sections is re
18、quired 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 bottom poured products, a minimum of sixsamples shall be examined and they shall represent the top andbottom
19、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 random, from the last usable plate poured. Whentwo usable plates constitute a heat, two of the sample ingotssha
20、ll 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 between manufacturer and purchaser.7.2.3 For strand cast products, a minimum of six samplesrepresenting the firs
21、t, middle, and last portion of the heat castshall be examined. At least one sample shall be taken fromeach strand.7.3 MacroetchSpecimens representative of cross sectionsof billets shall be macroetched and rated in accordance withMethod E 381 in hydrochloric acid and water (1:1) at 160 to180F 70 to 8
22、0C. Such specimens shall not exceed S2, R2,and C2 of Method E 381.7.4 Inclusion RatingThe specimens shall be38 by34 in.10 by 20 mm and shall be taken from an area halfwaybetween the center and outside of the billet. The polished faceshall be longitudinal to the direction of rolling. The scale usedfo
23、r rating the specimens shall be the Jernkontoret chartdescribed in Test Methods E45, Plate I-r. Fields with sizes ornumbers of all types of inclusions intermediate betweenconfigurations shown on the chart shall be classified as thelesser of the rating number. The worst field of each inclusiontype fr
24、om 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 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 specifi
25、callyordered and certified to Supplementary Requirement S4, TypeA inclusion ratings shall not exceed 3.0 thin and 2.0 heavy. SeeS4.1.8. Grain Size8.1 The steels covered by this specification shall have thecapability of showing a fine fracture grain size (approximatelyASTM No. 8 in accordance with Te
26、st Methods E112) whenquenched from normal austenitizing temperatures not exceed-ing 1550F 840C.9. Decarburization and Surface Imperfections9.1 Decarburization and surface imperfections shall notexceed the limits specified in Tables 4 and 5. Decarburizationshall be measured using the microscopical me
27、thods describedin Test Method E 1077.10. Microstructure10.1 When annealing is specified in the order, the structureshall be rated and reported in accordance with Guide A 892 asfollows:10.1.1 Carbide Size (CS)As the appropriate carbide sizeis dependent on application, the limits shall be as agreed up
28、onbetween manufacturer and purchaser.TABLE 1 CompositionA,BName C Mn P (max) S (max) Si Cr Ni (max) Mo Cu (max) O (max)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.
29、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 0.80-1.10 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 quot
30、ed shall not be intentionally added to the steel without the agreement of the purchaser.BIntentional additions of calcium 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
31、 be determined in accordance with Test Method E 1019.DTotal aluminum content.ESpecified element ranges meet the requirements 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
32、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 UnitsThin Series Heavy SeriesA212 A112B2 B1C12 C12D1 D1A 295/A 295M 05210.1.2 Carbide Network (CN)As the network is influ-enced by section size, the limits shall be as agreed uponbetween m
33、anufacturer 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.10.2 The material shall be free from excessive carbidesegregation.11. Hardness11.1 When a
34、nnealing is specified in the order, the steel shallhave a completely spheroidized microstructure and a hardnessas specified in Table 6.11.2 Small sizes where Rockwell B scale hardness readingsare impractical shall have a maximum tensile strength of110 000 psi (760 MPa).11.3 Hardness and tensile test
35、s shall be in accordance withtest methods described in Test Methods A 370.12. Inspection12.1 The manufacturer shall afford the purchasers inspectorall reasonable facilities necessary to satisfy him that thematerial is being produced and furnished in accordance withthis specification. Mill inspection
36、 by the purchaser shall notinterfere unnecessarily with the manufacturers operations. Alltests and inspections shall be made at the place of manufacture,unless otherwise agreed to.13. Certification and Reports13.1 Upon request of the purchaser in the contract or order,a manufacturers certification t
37、hat the material was manufac-tured and tested in accordance with this specification, togetherwith a report of the test results, shall be furnished at the timeof shipment. Special requirements agreed to at the time ofpurchase shall be noted on the certification.TABLE 4 Decarburization and Surface Imp
38、erfections 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 0.10Over 0.500 12.5 to 0.
39、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-Finished AnnealedBars T
40、ubes 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 75.0 to 4.000 100.0,
41、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 hot-rolled annealed 207
42、 . . .Coils annealed, cold-drawn (stress-relieved). 92Coils, bars, and annealed, cold-drawnA248 . . .tubesTubes annealed, cold-rocked 331 . . .ACold-swaged material is not included.A 295/A 295M 053SUPPLEMENTARY REQUIREMENTSOne or more of the supplementary requirements described below apply when incl
43、uded in thepurchasers 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 not negate any
44、of therequirements in the body of the specification.S1. Titanium ContentS1.1 The purchaser may specify that the analysis of titaniumbe provided by agreement with the steel manufacturer.S2. “SAM” Inclusion Rating SystemS2.1 The purchaser may specify that the “SAM” inclusionrating system described in
45、Method E of Test Methods E45beused in addition to the micro-inclusion rating system describedin 7.4.S2.2 SamplingSee 7.2.S2.3 LimitsThe “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 purchase
46、r may specify that the magnetic particlemethod described below be used in addition to the micro-inclusion rating system described in 7.4. The magnetic particlemethod measures bearing steel cleanliness by evaluating thetotal length of macro-inclusions for a stated area or per unitarea. Results are ex
47、pressed in millimeters per square metre.S3.2 SamplingSee 7.2.S3.3 Test specimens shall be straight cylinder quarter sec-tion samples prepared 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 mea
48、n 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 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 al
49、l six specimens shall not exceed 200 mm/m2.S4. Sulfur Requirement for MachinabilityS4.1 A sulfur content in the range of 0.0150.030 % may bespecified for improved machinability.S4.2 When this supplementary requirement is specified, thesulfide (Type A) ratings of 7.4 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 whenappli
