1、Designation: A 839 02Standard Specification forIron-Phosphorus Powder Metallurgy (P/M) Parts for SoftMagnetic Applications1This standard is issued under the fixed designation A 839; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, t
2、he year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers parts produced from iron-phosphorus powder metallurgy materials. These parts are
3、 usedin magnetic applications requiring higher permeability andelectrical resistivity and lower coercive field strength thanattainable routinely from parts produced from iron powder.1.2 Two powder types are covered; Type I containingnominally 0.45 % phosphorus, and Type II containing nomi-nally 0.8
4、% phosphorus.1.3 This specification deals with P/M parts in the sintered orannealed condition. Should the sintered parts be subjected toany secondary operation that causes mechanical strain, such asmachining or sizing, they should be resintered or annealed.1.4 The values stated in customary (cgs-emu
5、 and inch-pound) units are to be regarded as standard. The values givenin parentheses are mathematical conversions to SI units whichare provided for information only and are not consideredstandard.2. Referenced Documents2.1 ASTM Standards:A 34/A 34M Practice for Procurement, Testing and Sam-pling of
6、 Magnetic Materials2A 596/A 596M Test Method for Direct Current MagneticProperties of Materials Using the Ballistic Method andRing Specimens2A 773/A 773M Test Method for dc Magnetic Properties ofMaterials Using Ring and Permeameter Procedures withdc Electronic Hysteresigraphs2B 328 Test Method for D
7、ensity, Oil Content, and Intercon-nected Porosity of Sintered Powder Metal Structural Partsand Oil-Impregnated Bearings3E 1019 Test Methods for Determination of Carbon, Sulfur,Nitrogen, and Oxygen in Steel and in Iron, Nickel, andCobalt Alloys43. Ordering Information3.1 Purchase orders for parts con
8、forming to this specifica-tion shall include the following information:3.1.1 Reference to this specification and year of issue/revision.3.1.2 The type of powder to be used (see 4.1 and Table 1).3.1.3 Reference to an applicable part drawing.3.1.4 Quantity required.3.1.5 A critical cross section of th
9、e part shall be defined andso indicated on the applicable part drawing. The location of thecritical section is by mutual agreement between the user andthe producer (see 5.2).3.1.6 Magnetic property requirements if they are other thanstated in Table 2.3.1.7 Whether certification of chemical analysis
10、or magneticproperty evaluation is required (see Sections 4 and 6).3.1.8 Marking and packaging requirements (see Section 11).3.1.9 Whether testing for magnetic aging is required.3.1.10 Exceptions to this specification or special require-ments such as functional testing, as mutually agreed uponbetween
11、 the producer and the user.4. Chemical Composition4.1 The chemical composition of the parts shall conform tothe requirements prescribed in Table 1.4.2 Chemical analysis for phosphorus shall be determinedby wet chemistry in accordance with a method to be agreedupon between the user and the producer.
12、Analysis of carbon,oxygen, and nitrogen shall be done in accordance with TestMethods E 1019.5. Sintered Density Requirements5.1 Magnetic and residual induction of P/M parts stronglydepend on density. The density of P/M parts is determined bythe compressibility of the powder, the compacting pressure,
13、and sintering practice (temperature, time, and atmosphere).1This specification is under the jurisdiction of ASTM Committee A06 onMagnetic Properties and is the direct responsibility of Subcommittee A06.02 onMaterials Specifications.Current edition approved Oct. 10, 2002. Published November 2002. Ori
14、ginallypublished as A 839 85. Last previous edition A 839/A 839M 96.2Annual Book of ASTM Standards, Vol 03.04.3Annual Book of ASTM Standards, Vol 02.05.4Annual Book of ASTM Standards, Vol 03.05.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, Unite
15、d States.5.2 Parts produced in conformance with this specificationshall have a minimum sintered density of 6.8 g/cm3(6800kg/m3) in the critical section of the part. The critical sectionshall be defined by agreement between the user and theproducer.5.3 Sintered density shall be determined in accordan
16、ce withTest Method B 328.6. Magnetic Property Requirements6.1 Due to the nature of P/M parts production, magnetictesting of each lot is not required by this specification.However, it is strongly recommended that the user require theproducer to conduct periodic magnetic evaluations and tocertify the
17、results obtained. Such magnetic property evalua-tions shall be conducted in the following manner.6.2 When requested, each lot of parts should be sinteredwith at least one and preferably three ring test specimens whichcomply with the geometric requirements listed in PracticeA 34/A 34M. The ring speci
18、men(s) shall be produced from thesame mixed lot of powder used to produce the parts.6.3 The dc magnetic properties shall be determined inaccordance with Test Methods A 596/A 596M or A 773/A 773M.6.4 For the purpose of this specification, only the coercivefield strength determined from a maximum appl
19、ied magneticfield strength of 15 Oe (1200 A/m) needs to be determined.Other magnetic properties may be specified by mutual agree-ment between the user and the producer.6.5 Coercive Field Strength RequirementsThree grades,defined by coercive field strength, are stipulated by thisspecification and are
20、 listed in Table 2. The coercive fieldstrength requirements for Type I are based on interlaboratorystudy conducted by ASTM Committee B09. The requirementsfor Type II are based on both interlaboratory study andtechnical literature.6.6 Magnetic AgingNitrogen introduced during sinteringcan cause time-d
21、ependent degradation of magnetic properties.Therefore, when requested by the user, the producer shall testfor aging. To determine the susceptibility of the parts to aging,the test ring(s) should be heated for either 100 h at 150C or600 h at 100C and the coercive field strength remeasured. Achange in
22、 coercive field strength of 10 % or more of theoriginal value is evidence that aging has occurred.6.7 Since magnetic properties are strongly affected byprocess conditions, refer to the Appendix X1-Appendix X3 fortypical values and explanatory notes.7. Workmanship, Finish and Appearance7.1 The parts
23、shall be uniform in composition and uniformin density within critical sections.7.2 If parts are sectioned or fractured, there shall be noreadily recognizable defects.8. Sampling8.1 A lot shall consist of parts of the same form anddimensions, produced from a single mixed powder batch andfrom an uncha
24、nged process, without discontinuity in produc-tion, and submitted for inspection at one time.8.2 The user and the producer shall agree upon a represen-tative number of specimens for testing.9. Rejection and Rehearing9.1 Parts that fail to conform to the requirements of thisspecification may be rejec
25、ted. Rejection should be reported tothe producer or supplier promptly and in writing. In case ofdissatisfaction with the results of the test, the producer orsupplier may make claim for a rehearing.9.2 The disposition of rejected parts shall be subject toagreement between the user and the producer.10
26、. Certification10.1 When specified in the purchase order or contract, theuser shall be furnished certification that samples representingeach lot have either been tested or inspected as directed in thisspecification and the requirements have been met.10.2 When specified in the purchase order or contr
27、act, areport of the test results shall include:10.2.1 Chemical composition,10.2.2 Part density in the critical section,10.2.3 Magnetic test results, if required by the user, and10.2.4 The results of any other tests stipulated in thepurchase order or contract.11. Packaging and Package Marking11.1 Pac
28、kaging shall be subject to agreement between theuser and the producer.11.2 Parts furnished under this specification shall be in acontainer identified by the name or symbol of the partsproducer.12. Keywords12.1 coercive field strength; iron-phosphorus; powder met-allurgy (P/M); P/M partsTABLE 1 Chemi
29、cal Composition Requirements (in WeightPercent)Element Type I Type IIPhosphorus 0.40/0.50 0.75/0.85Carbon, max 0.03 0.03Oxygen, max 0.10 0.10Nitrogen, max 0.01 0.01IronAbalance balanceAIron is the balance by difference. Quantitative analysis of this element is notrequired.TABLE 2 Maximum Coercive Fi
30、eld Strength RequirementsGrade Powder Type I (0.45 % P) Powder Type II (0.8 % P)1 1.4 Oe (110 A/m) 1.2 Oe (96 A/m)2 1.8 Oe (140 A/m) 1.4 Oe (110 A/m)3 2.0 Oe (160 A/m) 1.7 Oe (140 A/m)A839022APPENDIXES(Nonmandatory Information)X1. TYPICAL MAGNETIC AND MECHANICAL PROPERTIES SINTERED AT 1120C INDISSOC
31、IATED AMMONIAX1.1 The data provided in this appendix are for informationonly and are not requirements in this specification. Typicalmagnetic and mechanical properties are listed in Table X1.1and Table X1.2, respectively. The influence of sintered densityis shown in both tables. For Table X1.1, the m
32、aximum fluxdensity, residual induction, and coercive field strength aremeasured from a maximum applied magnetic field strength of15 Oe (1200 A/m).TABLE X1.1 Typical Magnetic PropertiesType I Powder (0.45 % P) Type II Powder (0.8 % P)Sintered density, g/cm36.8 7.0 7.2 6.8 7.0 7.2(kg/m3) 6 800 7 000 7
33、 200 6 800 7 000 7 200(Relative) maximum permeability 2 300 2 600 2 700 3 500 4 000 4 500Maximum flux density, G 10 500 11 500 12 500 11 000 12 000 13 000(T) 1.05 1.15 1.25 1.10 1.20 1.30Residual induction, G 8 500 9 000 10 000 10 000 11 000 12 000(T) 0.85 0.90 1.00 1.00 1.10 1.20Coercive field stre
34、ngth, Oe 1.7 1.7 1.7 1.5 1.5 1.5(A/m) 140 140 140 120 120 120TABLE X1.2 Typical Mechanical PropertiesType I Powder (0.45 % P) Type II Powder (0.8 % P)Sintered density, g/cm36.8 7.0 7.2 6.8 7.0 7.2(kg/m3) 6 800 7 000 7 200 6 800 7 000 7 2000.2 % Offset yield strength, psi 30 000 32 000 35 000 40 000
35、45 000 50 000(MPa) 210 220 240 280 310 340Ultimate tensile strength, psi 40 000 45 000 50 000 48 000 50 000 55 000(MPa) 280 310 340 330 340 380Elongation in 1 in. (25.4 mm), % 577233Apparent hardness, HRB 40 45 55 55 65 70A839023X2. TYPICAL MAGNETIC AND MECHANICAL PROPERTIES SINTERED AT 1120C IN DRY
36、 HYDROGENX2.1 The data provided in this appendix are for informationonly and are not requirements in this specification. Typicalmagnetic and mechanical properties are listed in Table X2.1and Table X2.2, respectively. The influence of sintered densityis shown in both tables. For Table X2.1, the maxim
37、um fluxdensity, residual induction, and coercive field strength aremeasured from a maximum applied magnetic field strength of15 Oe (1200 A/m).TABLE X2.1 Typical Magnetic PropertiesType I Powder (0.45 % P) Type II Powder (0.8 % P)Sintered density, g/cm37.0 7.2 7.4 7.0 7.2 7.4(kg/m3) 7 000 7 200 7 400
38、 7 000 7 200 7 400(Relative) maximum permeability 3 000 3 200 3 600 4 000 4 500 5 000Maximum flux density, G 11 500 12 500 13 000 12 000 13 000 13 500(T) 1.15 1.25 1.30 1.20 1.30 1.35Residual induction, G 9 000 10 000 11 000 10 500 11 500 13 000(T) 1.00 1.00 1.10 1.05 1.15 1.30Coercive field strengt
39、h, Oe 1.7 1.7 1.7 1.3 1.3 1.3(A/m) 140 140 140 100 100 100TABLE X2.2 Typical Mechanical PropertiesType I Powder (0.45 % P) Type II Powder (0.8 % P)Sintered density, g/cm37.0 7.2 7.4 7.0 7.2 7.4(kg/m3) 7 000 7 200 7 400 7 000 7 200 7 4000.2 % Offset yield strength, psi 32 000 35 000 38 000 45 000 48
40、000 53 000(MPa) 220 240 260 310 330 360Ultimate tensile strength, psi 45 000 50 000 55 000 53 000 57 000 62 000(MPa) 310 340 380 360 390 430Elongation in 1 in. (25.4 mm), % 777444Apparent hardness, HRB 45 55 60 65 70 75A839024X3. TYPICAL MAGNETIC AND MECHANICAL PROPERTIES SINTERED AT 1260C IN DRY HY
41、DROGENX3.1 The data provided in this appendix are for informationonly and are not requirements in this specification. Typicalmagnetic and mechanical properties are listed in Table X3.1and Table X3.2, respectively. The influence of sintered densityis shown in both tables. For Table X3.1, the maximum
42、fluxdensity, residual induction, and coercive field strength aremeasured from a maximum applied magnetic field strength of15 Oe (1200 A/m).TABLE X3.1 Typical Magnetic PropertiesType I Powder (0.45 % P) Type II Powder (0.8 % P)Sintered density, g/cm37.0 7.2 7.4 7.0 7.2 7.4(kg/m3) 7 000 7 200 7 400 7
43、000 7 200 7 400(Relative) maximum permeability 3 000 3 200 3 600 5 000 5 500 6 000Maximum flux density, G 11 500 12 500 13 500 13 000 13 500 14 000(T) 1.15 1.25 1.35 1.30 1.35 1.40Residual induction, G 9 000 10 000 11 000 12 000 12 500 13 000(T) 0.9 1.00 1.10 1.20 1.25 1.30Coercive field strength, O
44、e 1.5 1.5 1.5 1.0 1.0 1.0(A/m) 120 120 120 80 80 80TABLE X3.2 Typical Mechanical PropertiesType I Powder (0.45 % P) Type II Powder (0.8 % P)Sintered density, g/cm37.0 7.2 7.4 7.0 7.2 7.4(kg/m3) 7 000 7 200 7 400 7 000 7 200 7 4000.2 % Offset yield strength, psi 32 000 39 000 41 000 45 000 48 000 53
45、000(MPa) 220 269 283 310 330 360Ultimate tensile strength, psi 45 000 55 000 60 000 50 000 55 000 58 000(MPa) 310 379 414 340 380 400Elongation in 1 in. (25.4 mm), % 10 12 15 2 2 2Apparent hardness, HRB 45 55 60 65 70 75ASTM International takes no position respecting the validity of any patent right
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47、ime by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will
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49、 International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).A839025
