1、Designation: B 439 08Standard Specification forIron-Base Powder Metallurgy (PM) Bearings (Oil-Impregnated)1This standard is issued under the fixed designation B 439; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、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. Scope*1.1 This specification covers porous metallic
3、 sleeve, flange,thrust, and spherical iron-base bearings that are produced frommixed metal powder utilizing powder metallurgy (PM) tech-nology and then impregnated with oil to supply operatinglubrication.1.2 Included are the specifications for the chemical, physi-cal, and mechanical requirements of
4、those ferrous PM materi-als that have been developed and standardized specifically foruse in the manufacture of these self-lubricating bearings.1.3 This specification accompanies Specification B 438/B 438M that covers the requirements for Bronze-Base PowderMetallurgy (PM) Bearings (Oil-Impregnated).
5、1.4 Typical applications for iron-base bearings are discussedin Appendix X1.1.5 Commercial bearing dimensional tolerance data areshown in Appendix X2, while engineering information regard-ing installation and operating parameters of PM bearings isincluded in Appendix X3. Additional useful informatio
6、n onself-lubricating bearings can be found in MPIF Standard 35(Bearings) and the technical literature.21.6 With the exception of density values for which theg/cm3unit is the industry standard, the values stated ininch-pound units are to be regarded as standard. The valuesstated in inch-pound units a
7、re to be regarded as standard. Noother units of measurement are included in this standard.1.7 The following safety hazards caveat pertains only to thetest methods described in this specification. This standard doesnot purport to address all of the safety concerns, if any,associated with its use. It
8、is the responsibility of the user of thisstandard to establish appropriate safety and health practicesand determine the applicability of regulatory limitations priorto use.2. Referenced Documents2.1 ASTM Standards:3B 243 Terminology of Powder MetallurgyB 328 Test Method for Density, Oil Content, and
9、 Intercon-nected Porosity of Sintered Metal Structural Parts andOil-Impregnated BearingsB 438/B 438M Specification for Bronze Powder Metallurgy(P/M) Bearings (Oil-Impregnated)B 939 Test Method for Radial Crushing Strength, K,ofPowder Metallurgy (P/M) Bearings and Structural Materi-alsE9 Test Methods
10、 of Compression Testing of Metallic Ma-terials at Room TemperatureE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE 1019 Test Methods for Determination of Carbon, Sulfur,Nitrogen, and Oxygen in Steel and in Iron, Nickel, andCobalt Alloys2.2 MPIF Stan
11、dard:4MPIF Standard 35 Materials Standards for PM Self-Lubricating Bearings2.3 IEEE/ASTM Standard:3SI 10 American National Standard for Use of the Interna-tional System of Units (SI): The Modernized MetricSystem1This specification is under the jurisdiction of ASTM Committee B09 on MetalPowders and M
12、etal Powder Products and is the direct responsibility of Subcom-mittee B09.04 on Bearings.Current edition approved April 1, 2008. Published May 2008. Replaces portionsof B 612 and B 782. Originally approved in 1966 to replace portions of B 202. Lastprevious edition approved in 2007 as B 439 07.2Mach
13、ine Design Magazine, Vol 54, No. 14, June 17, 1982, pp. 130142.3For 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 websit
14、e.4Available from Metal Powder Industries Federations, 105 College Road East,Princeton, NJ 08540, http:/www.infompif.org.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, United State
15、s.2.4 ISO Standard:5ISO 2795 Plain bearings from sintered metalDimensionsand tolerances3. Terminology3.1 DefinitionsThe definitions of the terms used in thisspecification are found in Terminology B 243. Additionaldescriptive information is available in the Related Materialssection of Volume 02.05 of
16、 the Annual Book of ASTMStandards.4. Classification4.1 This specification uses the established three-part alpha-numeric PM Material Designation Code to identify the ferrousmaterials used for self-lubricating bearings. The completeexplanation of this classification system is presented in AnnexA1.4.2
17、The following standard oil-impregnated iron-base bear-ing material compositions are contained in this specification:4.2.1 Prefix FIron Bearing Material:4.2.1.1 F-0000-K15Iron with 21 % oil.4.2.2 Prefix FIron-Carbon (Steel) Bearing Material:4.2.2.1 F-0005-K20Low carbon steel with 21 % oil.4.2.3 Prefi
18、x FCIron-CopperBearing Materials:4.2.3.1 FC-1000-K20Iron, 10 % copper with 22 % copperoil.4.2.3.2 FC-2000-K25Iron, 20 % copper with 22 % oil.4.2.4 Prefix FCTGIron-Bronze-Graphite (Diluted Bronze)Bearing Material:4.2.4.1 FCTG-3604-K22 Iron, 40 % bronze,34 %graphite with 17 % oil.4.2.5 Prefix FGIron-G
19、raphite Bearing Materials:4.2.5.1 FG-0303-K10Iron, 2 1/2 % graphite with 18 %oil.4.2.5.2 FG-0308-K16Steel, 2 % graphite with 18 % oil.5. Ordering Information5.1 Purchase orders or contracts for iron-base oil-impregnated PM bearings covered by this purchasing specifi-cation shall include the followin
20、g information:5.1.1 A copy of the bearing print showing dimensions andtolerances (Section 10),5.1.2 Reference to this ASTM specification, including dateof issue,5.1.3 Identification of bearing material by the PM MaterialDesignation Code (Section 4),5.1.4 Request for certification and test report doc
21、uments, ifrequired (Section 16),5.1.5 Type and grade of special lubricating oil, if required(6.2.3), and5.1.6 Instructions for special packaging, if required (Section17).6. Materials and Manufacture6.1 Porous Metallic Bearing:6.1.1 Porous iron-base bearings shall be produced by firstpreparing a mixt
22、ure of elemental iron powder with additions ofcopper, tin, pre-alloyed bronze or graphite powders to thespecified chemical composition and then compacting the pow-der mixture into a bearing configuration having the requiredgreen density6.1.2 The green bearings shall then be sintered in a furnacehavi
23、ng a protective atmosphere for a time and temperaturecycle that will produce the required sintered ferrous-base PMmaterial.6.1.3 After sintering, the iron-base bearings are normallysized to achieve the density, dimensional characteristics, con-centricity, and surface finish required of the finished
24、metallicbearing.6.2 Oil for Operating Lubrication:6.2.1 The interconnected or open porosity in the bearingsshall be filled to the required volume with lubricating oil, eitherby an extended soaking in the hot oil or preferably by a vacuumimpregnation operation.6.2.2 Amedium viscosity petroleum oil is
25、 the lubricant usedfor most bearing applications, but extreme operating conditionssuch as elevated temperatures, intermittent rotation, extremelylow speeds, or heavy loads may require a synthetic lubricant oran oil with a different viscosity.6.2.3 Unless otherwise specified by the purchaser, a high-
26、grade turbine oil with antifoaming additives and containingcorrosion and oxidation inhibitors, having a kinematic viscos-ity of 280 to 500 SSU (60 3 10-6to 110 3 10-6m2/s), (60 to110 cSt) at 100 F (38 C) is normally used as the generalpurpose lubricating oil.7. Chemical Composition7.1 Chemical Compo
27、sition SpecificationsEach iron-basePM bearing material shall conform to the chemical composi-tion requirements prescribed in Table 1 when determined on aclean test sample obtained from oil-free bearings.7.2 Limits on Nonspecified ElementsBy agreement be-tween the purchaser and the supplier, limits m
28、ay be establishedand chemical analyses required for elements or compounds notspecified in Table 1.8. Physical Properties8.1 Oil ContentFor each bearing material, the oil contentof the as-received bearing shall not be less than the minimumpercentage listed in Table 1.8.2 Impregnation EffciencyA minim
29、um of 90 % of theinterconnected porosity in the as-received bearings shall beimpregnated with lubricating oil.8.3 Impregnated DensityThe density of the sample bear-ings, when fully impregnated with lubricating oil, shall meetthe requirements specified in Table 1 for each bearing material.9. Mechanic
30、al Properties9.1 Radial Crushing StrengthThe radial crushing strengthof the oil-impregnated bearing material determined on a plainsleeve bearing or a test specimen prepared from a flange orspherical bearing shall meet the minimum and maximum (ifrequired) strength values listed in Table 1.5Available
31、from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.B43908210. Dimensions, Mass, and Permissible Variations10.1 This specification is applicable to iron-base PM sleeveand flange bearings havinga3to1maximum length to insidediameter ratio
32、 and a 20 to 1 maximum length to wall thicknessratio.TABLE 1 Specifications for Iron-Base Materials Used in PM BearingsMaterialDesignationCodeChemical Composition Requirements Physical Requirements Mechanical RequirementsIronmass %CombinedCarbonAmass %GraphiticCarbonmass %Coppermass %Tinmass %All Ot
33、hersmass %ImpregnatedDensityg/cm3Oil Contentvol %Radical Crushing Strength,(K)103psi (MPa)IronF-0000-K15 bal 0.3 max . . . 1.5 max . . . 2.0 max 5.6 to 6.0 21 min 15 min (100 min)Iron-Carbon (Steel)F-0005-K20 bal 0.3 to 0.6 . . . 1.5 max . . . 2.0 max 5.6 to 6.0 21 min 20 min (140 min)Iron-CopperFC-
34、1000-K20 bal 0.3 max . . . 9.0 to 11.0 . . . 2.0 max 5.6 to 6.0 22 min 20 min (140 min)FC-2000-K25 bal 0.3 max . . . 18.0 to 22.0 . . . 2.0 max 5.6 to 6.0 22 min 25 min (170 min)Iron-Bronze-Graphite(Diluted Bronze)FCTG-3604-K22 bal 0.5 max . . .B34.0 to 38.0 3.5 to 4.5 2.0 max 6.0 to 6.4 17 min 22 t
35、o 50 (150 to 340)Iron-GraphiteFG-0303-K10 bal 0.5 max 2.0 to 3.0 . . . . . . 2.0 max 5.6 to 6.0 18 min 10 to 25 (70 to 170)FG-0308-K16 bal 0.5 to 1.0 1.5 to 2.5 . . . . . . 2.0 max 5.6 to 6.0 18 min 16 to 45 (110 to 310)AMetallurgically combined carbon expressed as a percentage of the iron in the ma
36、terial composition.BThe graphitic carbon content is typically 0.5 to 1.3 %, the total carbon content shall be 0.5 to 1.3 %.FIG. 1 Standard Sleeve BearingFIG. 2 Standard Flange BearingFIG. 3 Standard Thrust BearingFIG. 4 Standard Spherical BearingB43908310.2 Standard sleeve, flange, thrust, and spher
37、ical PMbearings covered by this specification are illustrated by Figs.1-4. Most PM bearings are small and weigh less than one-quarter pound (100 g) but they can be produced in sizes thatwill accommodate shafts up to approximately 8 in. (200 mm)in diameter.10.3 Permissible variations in dimensions sh
38、all be withinthe limits specified on the bearing drawing accompanying theorder or shall be within the limits specified in the purchaseorder or contract.10.4 Recommended commercial tolerances for iron-basePM bearings are referenced throughout the tables in AppendixX2.10.5 Chamfers of 30 to 45 are gen
39、erally used on PMbearings to break the corners.11. Workmanship, Finish and Appearance11.1 The bearings should have a matte surface, and notshow oxidation. The surfaces of sized bearings should have asmooth bright finish.11.2 When cut or fractured, the exposed surface shallexhibit a uniform appearanc
40、e.11.3 If metallographic examination is performed to deter-mine degree of sintering, it should be done at 200 to 4003magnification. The iron materials should show a predominantlyferritic or pearlitic phase with uniformly dispersed graphiticcarbon (if present). High copper content Iron-Copper materia
41、lsshould show evidence of melted copper as a copper richskeletal network around a ferrous interior structure. DilutedBronze material should show a bronze phase with no visiblefree tin, dispersed throughout an iron matrix. The structureshould not show an excessive number of original particleboundarie
42、s.11.4 To verify the presence of oil in the bearing, theas-received bearing may be heated to approximately 300 F(150 C) for approximately 5 min. If oil is present, the surfaceswill show beads of oil being exuded from the open porosity.11.5 When bearings are ordered as being “dry-to-the-touch”to allo
43、w automated handling by the purchaser, the excesssurface oil is normally removed by a centrifugal tumblingoperation. It is important that the Oil Content test (13.3.1)beperformed after the surface drying treatment to make certainthat the required volume of lubricating oil is present.12. Sampling12.1
44、 LotUnless otherwise specified, a lot shall be definedas “a specific quantity of bearings manufactured under trace-able, controlled conditions as agreed to between the producerand user” (see Terminology B 243).12.2 Sampling PlanThe number of sample bearingsagreed to between the manufacturer and the
45、purchaser to beused for dimensional inspection (13.1), chemical analysis(13.2), physical tests (13.3), and mechanical tests (13.4) shallbe taken randomly from locations throughout the lot.13. Test Methods13.1 Dimensional Measurements:13.1.1 Using suitable measuring equipment, the inside di-ameter of
46、 the bearings shall be measured to the nearest 0.0001in. (0.0025 mm). The other bearing dimensions only requireinstrumentation capable of measuring to the tolerances speci-fied on the bearing drawing.13.2 Chemical Analysis:13.2.1 Oil ExtractionBearings and test samples must bedry and free of oil bef
47、ore performing chemical tests. Thepreferred method of oil removal is by use of the SoxhletApparatus specified in Test Method B 328. However, uponagreement between purchaser and supplier, a low-temperaturefurnace treatment 1000 to 1200 F (540 to 650 C) with aflowing nitrogen or other inert gas atmosp
48、here may be used tovolatilize any oil or lubricant that may be present.13.2.2 Test SampleAn oil-free test sample of chips shallthen be obtained by milling, drilling, filing, or crushing thebearings using clean dry tools without lubrication.13.2.3 Metallic ElementsThe chemical analysis for speci-fied
49、 metallic elements shall then be performed in accordancewith the test methods prescribed in Volume 03.05 of the AnnualBook of ASTM Standards or by another approved methodagreed upon between the manufacturer and the purchaser.13.2.4 Carbon AnalysisCarbon analysis is a set of proce-dures for determining the total carbon, the graphitic carbon,and the combined carbon in iron-base PM bearings. Totalcarbon is the sum of graphitic carbon and the total combinedcarbon.13.2.4.1 Total CarbonDetermine the total carbon in ac-cordance with Test Metho
