ASTM_A_839_-_15.pdf

Designation:A83915Standard Specification forIron-Phosphorus Powder Metallurgy Parts for Soft MagneticApplications1This standard is issued under the fixed designation A839;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 parentheses indicates the year of last reapproval.Asuperscript epsilon()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 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 wt.%phosphorus,and Type II containingnominally 0.8 wt.%phosphorus.1.3 This specification deals with powder metallurgy parts inthe sintered or annealed condition.Should the sintered parts besubjected to any secondary operation that causes mechanicalstrain,such as machining or sizing,they should be resintered orannealed.1.4 The values stated in SI units are to be regarded asstandard.The values given in parentheses are mathematicalconversions to customary(cgs-emu and inch-pound)units,which are provided for information only and are not consideredstandard.1.5 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2A34/A34M Practice for Sampling and Procurement Testingof Magnetic MaterialsA596/A596M Test Method for Direct-Current MagneticProperties of Materials Using the Ballistic Method andRing SpecimensA773/A773M Test Method for Direct Current MagneticProperties of Low Coercivity Magnetic Materials UsingHysteresigraphsB962 Test Methods for Density of Compacted or SinteredPowder Metallurgy(PM)Products Using ArchimedesPrincipleE1019 Test Methods for Determination of Carbon,Sulfur,Nitrogen,and Oxygen in Steel,Iron,Nickel,and CobaltAlloys by Various Combustion and Fusion Techniques3.Ordering Information3.1 Purchase orders for parts conforming 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 the 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 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 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.Analysis of carbon,oxygen,and nitrogen shall be done in accordance with TestMethods E1019.1This specification is under the jurisdiction of ASTM Committee A06 onMagnetic Properties and is the direct responsibility of Subcommittee A06.02 onMaterial Specifications.Current edition approved April 1,2015.Published April 2015.Originallyapproved in 1985.Last previous edition approved in 2008 as A83902(2008).DOI:10.1520/A0839-15.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.Sintered Density Requirements5.1 Magnetic and residual induction of powder metallurgyparts strongly depend on density.The density of powdermetallurgy parts is determined by the compressibility of thepowder,the compacting pressure,and sintering practice(temperature,time,and atmosphere).5.2 Parts produced in conformance with this specificationshall have a minimum sintered density of 6.8 Mg/m3in thecritical section of the part.The critical section shall be definedby agreement between the user and the producer.5.3 Sintered density shall be determined in accordance withTest Method B962.6.Magnetic Property Requirements6.1 Due to the nature of powder metallurgy partsproduction,magnetic testing of e