1、Designation:B43912Standard Specification forIron-Base Powder Metallurgy(PM)Bearings(Oil-Impregnated)1This standard is issued under the fixed designation B439;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A
2、 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 the requirements for porousiro
3、n-base metallic sleeve,flange,thrust,and spherical bearingsthat are produced from metal powders utilizing powder metal-lurgy(PM)technology and then impregnated with oil to supplyoperating lubrication.1.2 Listed are the chemical,physical,and mechanical speci-fications for those standardized ferrous P
4、M materials that havebeen developed specifically for the manufacture of self-lubricating bearings.1.3 This standard is a companion to Specification B438 thatcovers the requirements for porous oil-imptegnated bronze-base bearings.1.4 Typical applications for self-lubricating iron-base PMbearings are
5、discussed in Appendix X1.1.5 Commercial bearing dimensional tolerance data areshown in Appendix Appendix X2,while engineering informa-tion regarding installation and operating parameters of PMbearings is included in Appendix Appendix X3.Additionaluseful information on self-lubricating bearings can b
6、e found inMPIF Standard 35(Bearings),ISO 5755 and the technicalliterature.21.6 UnitsWith the exception of density values for whichthe use of the g/cm3unit is the long-standing practice of thePM industry,the values stated in inch-pound units are to beregarded as standard.The values given in parenthes
7、es aremathematical conversions to SI units that are provided forinformation only and are not to be regarded as standard1.7 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,a
8、ssociated with its use.It 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:3B243 Terminology of Powder MetallurgyB438 Specification for
9、Bronze-Base Powder Metallurgy(PM)Bearings(Oil-Impregnated)B939 Test Method for Radial Crushing Strength,K,ofPowder Metallurgy(PM)Bearings and Structural Materi-alsB962 Test Methods for Density of Compacted or SinteredPowder Metallurgy(PM)Products Using ArchimedesPrincipleB963 Test Methods for Oil Co
10、ntent,Oil-ImpregnationEfficiency,and Interconnected Porosity of Sintered Pow-der Metallurgy(PM)Products Using Archimedes Prin-cipleB966 Test Method for Permeability of Powder Metallurgy(PM)Bearings Using Nitrogen GasB970 Test Method for Cleanliness of Powder Metallurgy(PM)Bearings and Structural Par
11、tsE9 Test Methods of Compression Testing of Metallic Mate-rials at Room TemperatureE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE1019 Test Methods for Determination of Carbon,Sulfur,Nitrogen,and Oxygen in Steel,Iron,Nickel,and CobaltAlloys by Vari
12、ous Combustion and Fusion Techniques2.2 MPIF Standard:4MPIF Standard 35 Materials Standards for PM Self-Lubricating Bearings1This specification is under the jurisdiction of ASTM Committee B09 on MetalPowders and Metal Powder Products and is the direct responsibility of Subcom-mittee B09.04 on Bearin
13、gs.Current edition approved April 1,2012.Published September 2012.Replacesportions of B612 and B782.Originally approved in 1966 to replace portions ofB202.Last previous edition approved in 2008 as B439 08.DOI:10.1520/B0439-12.2Machine Design Magazine,Vol 54,No.14,June 17,1982,pp.130142.3For referenc
14、ed 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.4Available from Metal Powder Industries Federations,105 College Road East,Princ
15、eton,NJ 08540,http:/www.infompif.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 2.3 ISO Standards:5ISO 2795 Plain bearings from sintered metalDimensionsand tolerancesIS
16、O 5755 Sintered Metal Materials Specifications,3.Terminology3.1 DefinitionsThe definitions of the terms used in thisspecification are found in Terminology B243.Additional de-scriptive information is available in the Related Materialssection of Volume 02.05 of the Annual Book of ASTMStandards.4.Classification4.1 The following list of standardized iron-base oil-impregnated PM bearing material compositions classified bycomposition are included in this specification.Their completechemical,physical a
