ASTM A839-15

Standard Specification for Iron-Phosphorus Powder Metallurgy Parts for Soft Magnetic Applications

ABSTRACT
This specification covers parts produced from pressing and sintering of iron-phosphorus powders. The specification does not cover parts produced by metal injection molding. These parts are used in magnetic applications requiring higher permeability and electrical resistivity and lower coercive field strength than routinely attainable in parts produced from unalloyed iron powder. Two powder types are covered: Type I containing nominally 0.45% phosphorus, and Type II containing nominally 0.8% phosphorus. Apart from chemistry, parts produced to this specification shall have a minimum sintered density and maximum allowable coercive field strength. The minimum sintered density shall be 6.8 g/cm3 (6800 kg/m3) in the magnetically critical section of the part. Three grades with increasing maximum allowable coercive field strength are defined for each powder type. Detailed appendices showing the effect of sintering conditions on the magnetic and mechanical properties of parts made from both powders are included in this specification.
SCOPE
1.1 This specification covers parts produced from iron-phosphorus powder metallurgy materials. These parts are used in magnetic applications requiring higher permeability and electrical resistivity and lower coercive field strength than attainable routinely from parts produced from iron powder.  
1.2 Two powder types are covered; Type I containing nominally 0.45 wt.% phosphorus, and Type II containing nominally 0.8 wt.% phosphorus.  
1.3 This specification deals with powder metallurgy parts in the sintered or annealed condition. Should the sintered parts be subjected to any secondary operation that causes mechanical strain, such as machining or sizing, they should be resintered or annealed.  
1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to customary (cgs-emu and inch-pound) units, which are provided for information only and are not considered standard.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-Mar-2015
• ICS: 77.160 - Powder metallurgy
• Technical Committee: A06 - Magnetic Properties
• Drafting Committee: A06.02 - Material Specifications

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: A839 − 15
Standard Specification for
Iron-Phosphorus Powder Metallurgy Parts for Soft Magnetic
1
Applications
This standard is issued under the fixed designation A839; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope A773/A773M Test Method for Direct Current Magnetic
Properties of Low Coercivity Magnetic Materials Using
1.1 This specification covers parts produced from iron-
Hysteresigraphs
phosphorus powder metallurgy materials. These parts are used
B962 Test Methods for Density of Compacted or Sintered
in magnetic applications requiring higher permeability and
Powder Metallurgy (PM) Products Using Archimedes’
electrical resistivity and lower coercive field strength than
Principle
attainable routinely from parts produced from iron powder.
E1019 Test Methods for Determination of Carbon, Sulfur,
1.2 Two powder types are covered; Type I containing
Nitrogen, and Oxygen in Steel, Iron, Nickel, and Cobalt
nominally 0.45 wt.% phosphorus, and Type II containing
Alloys by Various Combustion and Fusion Techniques
nominally 0.8 wt.% phosphorus.
1.3 This specification deals with powder metallurgy parts in 3. Ordering Information
the sintered or annealed condition. Should the sintered parts be
3.1 Purchase orders for parts conforming to this specifica-
subjected to any secondary operation that causes mechanical
tion shall include the following information:
strain, such as machining or sizing, they should be resintered or
3.1.1 Reference to this specification and year of issue/
annealed.
revision.
1.4 The values stated in SI units are to be regarded as
3.1.2 The type of powder to be used (see 4.1 and Table 1).
standard. The values given in parentheses are mathematical
3.1.3 Reference to an applicable part drawing.
conversions to customary (cgs-emu and inch-pound) units,
3.1.4 Quantity required.
which are provided for information only and are not considered
3.1.5 A critical cross section of the part shall be defined and
standard.
so indicated on the applicable part drawing. The location of the
1.5 This standard does not purport to address all of the
critical section is by mutual agreement between the user and
safety concerns, if any, associated with its use. It is the
the producer (see 5.2).
responsibility of the user of this standard to establish appro-
3.1.6 Magnetic property requirements if they are other than
priate safety and health practices and determine the applica-
stated in Table 2.
bility of regulatory limitations prior to use.
3.1.7 Whether certification of chemical analysis or magnetic
2. Referenced Documents
property evaluation is required (see Sections 4 and 6).
2
2.1 ASTM Standards: 3.1.8 Marking and packaging requirements (see Section 11).
A34/A34M Practice for Sampling and Procurement Testing
3.1.9 Whether testing for magnetic aging is required.
of Magnetic Materials
3.1.10 Exceptions to this specification or special require-
A596/A596M Test Method for Direct-Current Magnetic
ments such as functional testing, as mutually agreed upon
Properties of Materials Using the Ballistic Method and
between the producer and the user.
Ring Specimens
4. Chemical Composition
1
This specification is under the jurisdiction of ASTM Committee A06 on
4.1 The chemical composition of the parts shall conform to
Magnetic Properties and is the direct responsibility of Subcommittee A06.02 on
Material Specifications. the requirements prescribed in Table 1.
Current edition approved April 1, 2015. Published April 2015. Originally
4.2 Chemical analysis for phosphorus shall be determined
approved in 1985. Last previous edition approved in 2008 as A839–02 (2008). DOI:
10.1520/A0839-15.
by wet chemistry in accordance with a method to be agreed
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
upon between the user and the producer. Analysis of carbon,
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
oxygen, and nitrogen shall be done in accordance with Test
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. Methods E1019.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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A839 − 15
TABLE 1 Chemical Composition Requirements (in Weight
tory study conducted by ASTM Committee B09. The require-
Percent)
ments for Type II are based on both interlaboratory study and
Element Type I Type II
technical literature.
Phosphorus 0.40/0.50 0.75/0.85
6.6 Magnetic Aging—Nitrogen introduced during sintering
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: A839 − 02 (Reapproved 2008) A839 − 15
Standard Specification for
Iron-Phosphorus Powder Metallurgy (P/M) Parts for Soft
1
Magnetic Applications
This standard is issued under the fixed designation A839; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This specification covers parts produced from iron-phosphorus powder metallurgy materials. These parts are used in
magnetic applications requiring higher permeability and electrical resistivity and lower coercive field strength than attainable
routinely from parts produced from iron powder.
1.2 Two powder types are covered; Type I containing nominally 0.45 % 0.45 wt.% phosphorus, and Type II containing
nominally 0.8 % 0.8 wt.% phosphorus.
1.3 This specification deals with P/M powder metallurgy parts in the sintered or annealed condition. Should the sintered parts
be subjected to any secondary operation that causes mechanical strain, such as machining or sizing, they should be resintered or
annealed.
1.4 The values stated in inch-poundSI units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that customary (cgs-emu and inch-pound) units, which are provided for information only and are not
considered standard.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
A34/A34M Practice for Sampling and Procurement Testing of Magnetic Materials
A596/A596M Test Method for Direct-Current Magnetic Properties of Materials Using the Ballistic Method and Ring Specimens
A773/A773M Test Method for Direct Current Magnetic Properties of Low Coercivity Magnetic Materials Using Hysteresig-
raphs
B328B962 Test Method for Density, Oil Content, and Interconnected Porosity of Sintered Metal Structural Parts and
Oil-Impregnated BearingsMethods for Density of Compacted or Sintered Powder Metallurgy (PM) Products Using
Archimedes’ Principle (Withdrawn 2009)
E1019 Test Methods for Determination of Carbon, Sulfur, Nitrogen, and Oxygen in Steel, Iron, Nickel, and Cobalt Alloys by
Various Combustion and Fusion Techniques
3. Ordering Information
3.1 Purchase orders for parts conforming to this specification 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.
1
This specification is under the jurisdiction of ASTM Committee A06 on Magnetic Properties and is the direct responsibility of Subcommittee A06.02 on Material
Specifications.
Current edition approved May 1, 2008April 1, 2015. Published June 2008April 2015. Originally approved in 1985. Last previous edition approved in 20022008 as
A839–02. –02 (2008). DOI: 10.1520/A0839-02R08.10.1520/A0839-15.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
A839 − 15
TABLE 1 Chemical Composition Requirements (in Weight
Percent)
Element Type I Type II
Phosphorus 0.40/0.50 0.75/0.85
Carbon, max 0.03 0.03
Oxygen, max 0.10 0.10
Nitrogen, max 0.01 0.01
A
Iron balance balance
TABLE 1 Chemical Composition Requirements (in Weight
Percent)
Element Type I Type II
Phosphorus 0.40/0.50 0.75/0.85
Carbon, max 0.03 0.03
Oxygen, max 0.10 0.10
Nitrogen, max 0.01 0.01
A
Iron balance balance
A
Iron is the balance by difference. Quantitative analysis of this element is not
required.
3.1.5 A critical cross section of the part shall be defined and so indicated on the applicable part drawing. The location of the
critical section is by mutual agreement between the user and the producer (see 5.2).
3.1.6 Magnetic property requirements if they are other than stated in Table 2.
3.1.7 Whether certification of
...