ASTM A848-01

Standard Specification for Low-Carbon Magnetic Iron

SCOPE
1.1 This specification covers the requirements for wrought low-carbon iron having a carbon content of 0.015 % or less with the remainder of the analysis being substantially iron.
1.1.1 Two alloy types are covered: Type 1 is a low-phosphorous grade and Type 2 contains a phosphorous addition to improve machinability.
1.2 This specification also covers alloys supplied by a producer or converter in the form and condition suitable for fabrication into parts which will be subsequently heat treated to create the desired magnetic characteristics. It covers alloys supplied in the form of forging billets, hot-rolled products, and cold-finished bar, wire, and strip.
1.3 This specification does not cover iron powders capable of being processed into magnetic components.
1.4 This specification does not cover flat-rolled, low-carbon electrical steels.
1.5 The values stated in customary (cgs-emu and inch-pound) units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units which are provided for information only and are not considered standard.

General Information

• Status: Historical
• Publication Date: 09-Dec-2001
• ICS: 77.140.40 - Steels with special magnetic properties
• Technical Committee: A06 - Magnetic Properties
• Drafting Committee: A06.02 - Material Specifications

Relations

• Replaced By: ASTM A848-01(2006) - Standard Specification for Low-Carbon Magnetic Iron
• Effective Date: 01-May-2006
• Referred By: ASTM A1126-23 - Standard Specification for Magnetic Pure Iron
• Effective Date: 10-Dec-2001

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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: A 848 – 01
Standard Specification for
Low-Carbon Magnetic Iron
This standard is issued under the fixed designation A 848; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope IEC Publication 60404-7 Ed. 1 Method of Measurement of
theCoercivityofMagneticMaterialsinanOpenMagnetic
1.1 This specification covers the requirements for wrought
Circuit
low-carbon iron having a carbon content of 0.015% or less
with the remainder of the analysis being substantially iron.
3. Ordering Information
1.1.1 Two alloy types are covered: Type 1 is a low-
3.1 Orders to this specification shall include as much of the
phosphorousgradeandType2containsaphosphorousaddition
following information as is required to describe the desired
to improve machinability.
material:
1.2 This specification also covers alloys supplied by a
3.1.1 ASTM specification number and alloy type.
producer or converter in the form and condition suitable for
3.1.2 DimensionsandTolerances—The tolerances are to be
fabricationintopartswhichwillbesubsequentlyheattreatedto
mutually agreed upon between the user and the producer.
create the desired magnetic characteristics. It covers alloys
3.1.3 Quantity (weight or number of pieces).
suppliedintheformofforgingbillets,hot-rolledproducts,and
3.1.4 Form and condition
cold-finished bar, wire, and strip.
3.1.5 Magnetic property requirements if they are otherwise
1.3 This specification does not cover iron powders capable
than stated herein.
of being processed into magnetic components.
3.1.6 Certification of chemical analysis or magnetic prop-
1.4 This specification does not cover flat-rolled, low-carbon
erty evaluation, or both.
electrical steels.
3.1.7 Marking and packaging
1.5 The values stated in customary (cgs-emu and inch-
3.1.8 EndUse—Wheneverpossible,theusershouldspecify
pound) units are to be regarded as standard. The values given
whethertheproductwillbemachined,blankedintoflatpieces,
in parentheses are mathematical conversions to SI units which
blanked and formed, or deep drawn to shape.This information
are provided for information only and are not considered
willhelptheproducerprovidethemostsuitableproductforthe
standard.
user’s fabrication practice.
2. Referenced Documents 3.1.9 Exceptions to this specification or special require-
ments.
2.1 ASTM Standards:
A 34/A 34M Practice for Sampling and Procurement Test-
4. Chemical Composition
ing of Magnetic Materials
4.1 Alloyssuppliedtothisspecificationshallconformtothe
A 341/A 341M Test Method for Direct Current Magnetic
requirements in Table 1. Three of the elements listed in Table
Properties of Materials Using D-C Permeameters and the
2 1, namely vanadium, titanium, and aluminum, are not required
Ballistic Test Methods
but may be added to suppress magnetic aging. If present, they
A 596/A 596M Test Method for Direct-Current Magnetic
must be analyzed and reported.
Properties of Materials Using the Ballistic Method and
Ring Specimens
5. Form and Condition
A 773/A 773M Test Method for dc Magnetic Properties of
5.1 These two alloys are capable of being produced in a
Materials Using Ring and Permeameter Procedures with
2 wide variety of forms and conditions for fabrication into
dc Electronic Hysteresigraphs
magneticcomponents.Thedesiredformandconditionshallbe
2.2 Other:
discussed with the producer to assure receiving the correct
product. Available forms and conditions are:
5.1.1 Forging Billet—Hot worked and surface conditioned
This specification is under the jurisdiction of ASTM Committee A06 on
by grinding.
Magnetic Properties and is the direct responsibility of Subcommittee A06.02 on
Materials Specifications.
Current edition approved December 10, 2001. Published January 2002. Origi-
nally published as A848–85. Last previous edition A848/A848M–96. Available from American National Standards Institute, 25 W. 43rd St., 4th
Annual Book of ASTM Standards, Vol 03.04. Floor, New York, NY 10036.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
A 848–01
TABLE 1 Chemical Requirements (Weight Percent)
6.3 Heat Treatment—It is recommended that the user
Alloy Type 1 Alloy Type 2 specify the desired heat treatment method to be applied to the
test specimens.
Carbon, max 0.020 0.020
Manganese, max 0.35 0.35
6.3.1 When relay condition is specified, the test specimen
Silicon, max 0.15 0.15
shall be heat treated in a dry forming gas atmosphere (5 to
Phosphorous 0.030 max 0.10/0.18
15% hydrogen in nitrogen with a dew point less than−40°C)
Sulfur, max 0.025 0.025
Chromium, max 0.20 0.20
at a temperature of 845°C for1hat temperature and cooled at
Nickel, max 0.15 0.15
a rate from 55 to 100°C/h to 500°C and cooled at any rate
Vanadium, max 0.10 0.10
thereafter.
Titanium, max 0.10 0.10
Aluminum, max 0.10 0.10
6.3.2 If relay condition is not specified and no heat-treating
Iron balance balance
procedure is specified by the user, the producer is free to
choose a heat treatment procedure. Refer to Appendix X3 for
heat treatment recommendations.
5.1.2 Hot-Rolled Product—Hot rolled; hot rolled and acid
6.4 Test Method—Magnetic testing shall be conducted in
cleaned;hotrolledandannealed;hotrolled,annealed,andacid
accordancewithTestMethodsA341/A341M,A596/A596M,
cleaned; hot rolled and mechanically cleaned; mechanical
or A773/A773M or by use of a coercimeter. Under this
properties as specified.
specification only the coercive field strength (H ) must be
c
5.1.3 Cold-Finished Bars—Cold drawn, centerless ground,
measured.
mechanical properties as specified; or relay condition.
6.5 Requirements—The coercive field strength (H ) mea-
c
5.1.3.1 Relay condition applies to 1 in. (25.4 mm) round
sured from a maximum magnetic flux density of 15 kG (1.5T)
and less in diameter and certain shapes supplied in the
or higher must meet the maximum values listed in Table 2
cold-workedconditionhavingupto25%reductioninareaand
whenthetestspecimenisheattreatedinaccordancewith6.3.1.
capable of meeting Class 2 magnetic property requirements as
6.5.1 When a coercimeter is used, the supplier must be able
defined in 6.5.
todemonstratethatthefluxdensityinthetestspecimenreaches
5.1.4 Strip—Cold rolled, cold rolled and annealed, deep
at least 15 kG (1.5 T) during the magnetization cycle. In
draw quality, mechanical properties as specified; or relay
addition, the test equipment and method should conform to
condition.
those specified in IEC Publication 60404-7.
5.1.4.1 Relay condition applies to cold-rolled strip 0.020 to
0.200 in. (0.51 to 5.1 mm) thick having up to 25% reduction
7. Packaging and Marking
in thickness and capable of meeting Class 2 magnetic property
7.1 Packaging shall be subject to agreement between the
requirements as defined in 6.5.
producer and the user.
5.1.4.2 Ordering information for strip must include edge
7.2 Material furnished under this specification shall be
condition and mechanical property requirements.
identifiedbythenameorsymboloftheproducer,byalloytype,
5.1.5 Wire—Cold drawn, annealed, mechanical properties
melt number, and material size. Each lot applied on a given
as specified or relay condition.
order must be identified and packaged separately.
5.1.5.1 Relay condition applies to cold-drawn wire when
capable of being supplied having up to 25% reduction in area
8. Investigation of Claim
and capable of meeting Class 2 magnetic property require-
8.1 Where any order fails to meet the requirements of this
ments as defined in 6.5.
specification, disposition of the material so designated shall be
6. Magnetic Property Requirements
subject to agreement between the user and the producer.
6.1 Density—The density for test purposes is 7.86
3 3
9. Keywords
g/cm (7860 kg/m ).
6.2 Test Specimen—Whene
...