1、Designation: B 848 05Standard Specification forPowder Forged (P/F) Ferrous Materials1This standard is issued under the fixed designation B 848; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in
2、parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers powder forged ferrous materi-als fabricated by hot densification of atomized prealloyed oriron powders and intended f
3、or use as structural parts.1.2 This specification covers powder forged parts madefrom the following materials:1.2.1 Compositions:1.2.1.1 P/F-10XX Carbon Steel (produced from atomizediron powder and graphite powder),1.2.1.2 P/F-10CXX Copper-Carbon Steel (produced fromatomized iron powder, copper and
4、graphite powders),1.2.1.3 P/F-11XX Carbon Steel with manganese sulfide forenhanced machinability (produced from atomized iron powder,manganese sulfide, and graphite powders),1.2.1.4 P/F-11CXX Copper-Carbon Steel with manganesesulfide for enhanced machinability (produced from atomizediron powder, cop
5、per, manganese sulfide, and graphite pow-ders),1.2.1.5 P/F-42XX Nickel-Molybdenum Steel (producedfrom prealloyed atomized iron-nickel-molybdenum powderand graphite powder),1.2.1.6 P/F-46XX Nickel-Molybdenum Steel (producedfrom prealloyed atomized iron-nickel-molybdenum powderand graphite powder),1.2
6、.1.7 P/F-44XX Molybdenum Steel (produced from pre-alloyed atomized iron-molybdenum powder and graphite pow-der), and1.2.1.8 P/F-49XX Molybdenum Steel (produced from pre-alloyed atomized iron-molybdenum powder and graphite pow-der).NOTE 1Alloy composition designations are modifications of theAISI-SAE
7、 nomenclature. For example: 10CXX designates a plain carbonsteel containing copper and XX amount of carbon. Compositional limitsof alloy and impurity elements may be different from theAISI-SAE limits.Chemical composition limits are specified in Section 6.NOTE 2XX designates the forged carbon content
8、, in hundredths of apercent, that is specified by the purchaser for the application. For a givenspecified carbon content, the permissible limits shall be as specified in 6.2.1.2.2 Grades:1.2.2.1 Grade ADensity equivalent to a maximum of0.5 % porosity. The minimum density of those sections of thepowd
9、er forged part so designated by the applicable partdrawing shall not be less than the value specified in Table 1.1.2.2.2 Grade BDensity equivalent to a maximum of1.5 % porosity. The minimum density of those sections of thepowder forged part so designated by the applicable partdrawing shall not be le
10、ss than the value specified in Table 1.1.3 Property values stated in inch-pound units are thestandard. Conversion factors to SI units may be approximate.2. Referenced Documents2.1 ASTM Standards:2A 255 Test Method for Determining Hardenability of SteelB 243 Terminology of Powder MetallurgyB311 Test
11、Method for Density Determination for PowderMetallurgy (P/M) Materials Containing Less Than TwoPercent PorosityB 795 Test Method for Determining the Percentage ofAlloyed or Unalloyed Iron Contamination Present inLow-Alloy Powder Forged (P/F) Steel PartsB 796 Test Method for Nonmetallic Inclusion Cont
12、ent ofPowders Intended for Powder Forging (P/F) ApplicationsB 797 Test Method for Surface Finger Oxide PenetrationDepth and Presence of Interparticle Oxide Networks inPowder Forged (P/F) Steel PartsB 934 Test Method for Effective Case Depth of FerrousPowder Metallurgy (P/M) Parts Using Microindentat
13、ionHardness MeasurementsE3 Practice for Preparation of Metallographic SpecimensE8 Test Methods for Tension Testing of Metallic MaterialsE18 Test Methods for Rockwell Hardness and RockwellSuperficial Hardness of Metallic MaterialsE23 Test Methods for Notched Bar Impact Testing ofMetallic MaterialsE29
14、 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE 350 Test Methods for ChemicalAnalysis of Carbon Steel,Low-Alloy Steel, Silicon Electrical Steel, Ingot Iron, andWrought Iron1This specification is under the jurisdiction of ASTM Committee B09 on MetalPow
15、ders and Metal Powder Products and is the direct responsibility of Subcom-mittee B09.11 on Near Full Density Powder Metallurgy Materials.Current edition approved Oct. 1, 2005. Published October 2005. Originallyapproved in 1994. Last previous edition approved in 2001 as B 848 01.2For referenced ASTM
16、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.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM
17、International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.E 415 Test Method for Optical Emission Vacuum Spectro-metric Analysis of Carbon and Low-Alloy SteelE 562 Test Method for Determining Volume Fraction bySystematic Manual Point CountE 1019 Test Methods f
18、or 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 MPIF Standard:3MPIF 35 Materials Standards for P/F Steel Parts3. Terminology3.1 DefinitionsDefinitions of powde
19、r metallurgy termscan be found in Terminology B 243. Additional descriptiveinformation is available in the Related Material Section of Vol.02.05 of the Annual Book of ASTM Standards.3.2 Descriptions of Terms Specific to This Standard:3.2.1 core regiona core region is one where there is eitherno deca
20、rburization as determined by the procedure in 9.3.4 orthere is no hardened surface as determined by the procedure inS2.2.3.2.2 critical regiona critical region of a part is one thatrequires a density level or a microstructural characteristic to beseparately specified.4. Ordering Information4.1 Order
21、s for parts conforming to this specification shallinclude the following:4.1.1 Alloy composition, including carbon content (see1.2.1, Section 6, and Table 2),4.1.2 Grade (minimum density requirementsee 1.2.2 andSection 7),4.1.3 Heat treatment condition and hardness (see 8.1.3,8.1.4, and 8.2.3),4.1.4
22、Location of critical regions (see 3.2.2),4.1.5 Whether functional or mechanical property testing isrequired, what type of testing is required, and what perfor-mance level is required (see 8.1.1, 8.1.2, 8.2.1, and 8.2.2),4.1.6 Whether the purchaser desires that his representativeinspect or witness th
23、e inspection and testing of the materialprior to shipment (see 11.1 and 11.2),4.1.7 Whether there are special microstructural require-ments (see Section 9 and S4),4.1.8 Whether certification of the material is required (seeSection 13),3Available from Metal Powder Industries Federation, 105 College R
24、oad East,Princeton, NJ 085406692.TABLE 1 Minimum Density for Selected Powder Forged SteelCompositions (Fully Annealed Heat Treatment ConditionFerrite/Pearlite Microstructure)A,BChemical CompositionDensity (g/cm3)Grade A(0.5 % porosity)CGrade B(1.5 % porosity)CP/F-1040 7.81 7.74P/F-1060 7.81 7.73P/F-
25、10C40 7.81D7.74DP/F-10C60 7.81D7.73DP/F-1140 7.79 7.71P/F-1160 7.78 7.70P/F-11C40 7.79D7.71DP/F-11C60 7.79D7.71DP/F-4220 7.82 7.74P/F-4240 7.81 7.73P/F-4260 7.80 7.72P/F-4420 7.82 7.74P/F-4440 7.81 7.73P/F-4460 7.81 7.73P/F-4620 7.82 7.74P/F-4640 7.81 7.73P/F-4660 7.81 7.73P/F-4680 7.80 7.72P/F-4920
26、 7.83 7.75P/F-4940 7.82 7.74P/F-4960 7.81 7.74AQuench-hardening and tempering will reduce the density values. Normalizedsamples may have lower density values then fully annealed materials.BFor the purpose of determining conformance with this specification, measuredvalues shall be rounded “to the nea
27、rest unit” in the last right-hand digit used inexpressing the specification limit, in accordance with the rounding-off method ofPractice E29.CBased on the method described in Smith, D. W., “Calculation of the Pore-FreeDensity of P/M Steels: Role of Microstructure and Composition,” The InternationalJ
28、ournal of Powder Metallurgy, Vol 28, No. 3, 1992, p. 259. Calculations based on350 ppm max oxygen content and all oxygen combined as 3MnO Al2O3 3SiO2.DThe method described by Smith is not considered applicable to steels withadmixed copper additions. Pore-free densities for these materials were deter
29、-mined by experiment.TABLE 2 Chemical Composition Requirements for PowderForged Parts (Weight %)AElement P/F-10XX P/F-10CXX P/F-11XX P/F-11CXXNickel, max 0.10 0.10 0.10 0.10Molybdenum,max0.05 0.05 0.05 0.05Manganese 0.100.25 0.100.25 0.300.60B0.300.60BCopper 0.30 max 1.82.2 0.30 max 1.82.2Chromium,m
30、ax0.10 0.10 0.10 0.10Sulfur, max 0.025 0.025 0.23B0.23BSilicon, max 0.03 0.03 0.03 0.03Phosphorus,max0.03 0.03 0.03 0.03CarbonCCCCOxygenDDDDTotal Iron BalanceEBalanceEBalanceEBalanceEElement P/F-42XX P/F-46XX P/F-44XX P/F-49XXNickel 0.400.50 1.752.00 0.10 max 0.10 maxMolybdenum 0.550.65 0.500.60 0.8
31、00.95 1.41.6Manganese 0.200.35 0.100.25 0.080.18 0.080.18Copper, max 0.15 0.15 0.15 0.15Chromium,max0.10 0.10 0.10 0.10Sulfur, max 0.03 0.03 0.03 0.03Silicon, max 0.03 0.03 0.03 0.03Phosphorus,max0.03 0.03 0.03 0.03CarbonCCCCOxygenDDDDTotal Iron BalanceEBalanceEBalanceEBalanceEAFor the purpose of de
32、termining conformance with this specification, measuredvalues shall be rounded “to the nearest unit” in the last right-hand digit used inexpressing the specification limit, in accordance with the rounding-off method ofPractice E29.BCovers manganese sulfide (MnS) additions of from 0.3 to 0.5 %. Thema
33、nganese content in solution is similar to P/F-10XX or P/F-10CXX, that is, 0.10to 0.25 %.CCarbon content shall be as specified by the purchaser.DWhen required, maximum oxygen content shall conform to the amountspecified by purchaser. See S1.EFor information only. Quantitative determination of this el
34、ement is not required.B8480524.1.9 Whether there is a maximum forged-oxygen content(see S1),4.1.10 Whether case hardening is required (see S2),4.1.11 Whether there is a maximum area percent porosityrequirement for critical regions (see 3.2.2 and S3), and4.1.12 ASTM designation and year of issue.5. M
35、aterials and Manufacture5.1 Make the structural parts by hot forging of powdermetallurgy (P/M) preforms in confined dies with or withoutsubsequent heat treatment. Prepare P/M preforms by pressingor by pressing and sintering material conforming to thedesignations in 1.2.1 and meeting the chemical com
36、positionsspecified in Section 6 and Table 2.6. Chemical Composition6.1 The hot forged material shall conform to the require-ments prescribed in Table 2.6.2 Unless otherwise specified, the hot forged carbon con-tent shall not deviate from that specified by the purchaser bymore than 60.05 weight perce
37、nt.6.3 Determine the concentration of the elements copper,chromium, manganese, molybdenum, nickel, phosphorus, andsilicon in accordance with Test Method E 415 or Test MethodE 350; X-ray fluorescence (XRF) or inductively coupledplasma, atomic emission spectrometry (ICP-AES) techniquesmay also be used
38、 for these analyses. Determine the concentra-tion of the elements carbon and sulfur in accordance with TestMethods E 1019.7. Density Requirement7.1 The minimum density of those sections of powderforged parts so designated by the applicable part drawing shallnot be less than the values specified in T
39、able 1.7.2 Determine the density of complete parts or sections ofparts in accordance with Test Method B311.8. Mechanical Property Requirements8.1 Mechanical Properties:8.1.1 The preferred method for verifying the acceptableperformance of a finished part is for the manufacturer and thepurchaser to ag
40、ree upon a qualification test to be performed onan actual part. The specific test should be determined followingconsideration of the function of the part. An example would bemeasuring the force needed to break teeth off a gear, using aprescribed test fixture.8.1.2 Where the part configuration permit
41、s, standard me-chanical property test specimens may be machined from thepart in the condition in which it is to be used. (Remove testspecimens from parts to be used in the quenched and temperedcondition after heat treatment of the part to ensure themicrostructure is representative of the actual part
42、.) The appli-cable part drawing or purchase order shall designate thelocation from which the mechanical property test specimensare to be removed and the type of specimen to be tested.8.1.3 The core hardness range of parts shall be in accor-dance with the applicable part drawing or purchase order.8.1
43、.4 The surface hardness range of parts shall be inaccordance with the applicable part drawing or purchase order.8.1.5 Typical mechanical properties of Grade A materialscovered by this specification are shown in Appendix X1.8.2 Mechanical Property Test Methods:8.2.1 Tensile Test MethodWhen requested,
44、 take tensiletest specimens from parts in accordance with the applicablepart drawing or purchase order. Test tensile specimens inaccordance with Test Methods E8. Determine yield strengthby the 0.2 % offset method.8.2.2 Impact Energy Test MethodWhen requested, takeCharpy V-notch impact test bars from
45、 parts in accordance withthe applicable part drawing or purchase order. Test impact barsin accordance with Test Methods E23; at room temperature,or, at a temperature agreed between the manufacturer andpurchaser.8.2.3 Hardness Test MethodDetermine hardness measure-ments in accordance with Test Method
46、s E18. Make corehardness measurements on sectioned parts within the coreregion of the part. Determine surface hardness measurementsin accordance with the applicable part drawing on the originalforged surface, or, if machined, on the machined part surface.9. Microstructure Requirements9.1 Surface Fin
47、ger Oxide Penetration:9.1.1 The maximum depth of penetration of surface fingeroxides from the finished part surface, for each designatedcritical region of a powder forged part, shall not exceed thatagreed upon between the manufacturer and purchaser. Desig-nate critical regions by the applicable part
48、 drawing or purchaseorder.9.1.2 Determine the surface finger oxide penetration inaccordance with Test Method B 797.9.2 Interparticle Oxide Networks:9.2.1 The extent of any interparticle oxide networks in eachdesignated critical region of a powder forged part shall notexceed that agreed upon between
49、the manufacturer and pur-chaser. Designate critical regions on the applicable part draw-ing or purchase order.9.2.2 Determine the interparticle oxide networks in accor-dance with Test Method B 797.9.3 Decarburization Depth:9.3.1 The maximum depth of complete decarburization(only ferrite present) of surfaces of powder forged parts shallnot exceed that agreed between the manufacturer and pur-chaser.9.3.2 The depth of total decarburization (totaldecarburization = complete decarburization + partial decarbur-ization), the depth at which core carbon content i
