ASTM A848-17

Standard Specification for Low-Carbon Magnetic Iron

ABSTRACT
This specification covers the standard requirements for wrought low-carbon iron having a carbon content of 0.015% or less with the remainder of the analysis being substantially iron. These alloys are not electrical steels such as are described in Specifications A 726 and A 840 but are instead primarily used in dc magnetic applications and are produced in a wide variety of mill forms such as forging billet and cold finished bar and wire as well as strip. Two alloy types are covered: Type 1 is a low-phosphorus grade and Type 2 contains a phosphorus addition to improve machinability. Apart from chemical requirements, alloy produced to this specification must exhibit guaranteed maximum values of coercive field strength when heat treated according to this specification. This specification has several useful appendices dealing with typical magnetic, physical and mechanical properties, heat treatment and magnetic aging.
SCOPE
1.1 This specification covers the requirements for wrought low-carbon iron typically having a carbon content of 0.015 % or less with the remainder of the chemical composition 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. Please refer to the following ASTM Standards for information regarding powdered metal materials and magnetic components: Specifications A811, A839, and A904.  
1.4 This specification does not cover flat-rolled, low-carbon electrical steels. Please refer to Specification A726 for information regarding these materials.  
1.5 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.  
1.6 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.  
1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-Mar-2017
• ICS: 77.140.40 - Steels with special magnetic properties
• Technical Committee: A06 - Magnetic Properties
• Drafting Committee: A06.02 - Material Specifications

Relations

• Refers: ASTM A340-23a - Standard Terminology of Symbols and Definitions Relating to Magnetic Testing
• Effective Date: 01-Dec-2023
• Refers: ASTM A340-19b - Standard Terminology of Symbols and Definitions Relating to Magnetic Testing
• Effective Date: 15-Oct-2019
• Refers: ASTM A340-19a - Standard Terminology of Symbols and Definitions Relating to Magnetic Testing
• Effective Date: 15-Jun-2019
• Refers: ASTM A340-19 - Standard Terminology of Symbols and Definitions Relating to Magnetic Testing
• Effective Date: 15-Feb-2019
• Refers: ASTM A340-18 - Standard Terminology of Symbols and Definitions Relating to Magnetic Testing
• Effective Date: 01-Jun-2018
• Refers: ASTM A340-17a - Standard Terminology of Symbols and Definitions Relating to Magnetic Testing
• Effective Date: 15-Oct-2017
• Refers: ASTM A340-17 - Standard Terminology of Symbols and Definitions Relating to Magnetic Testing
• Effective Date: 01-Jul-2017
• Refers: ASTM A340-16e1 - Standard Terminology of Symbols and Definitions Relating to Magnetic Testing
• Effective Date: 01-May-2016
• Refers: ASTM A340-16 - Standard Terminology of Symbols and Definitions Relating to Magnetic Testing
• Effective Date: 01-May-2016
• Refers: ASTM A340-15 - Standard Terminology of Symbols and Definitions Relating to Magnetic Testing
• Effective Date: 01-Oct-2015
• Refers: ASTM A340-14 - Standard Terminology of Symbols and Definitions Relating to Magnetic Testing
• Effective Date: 01-Oct-2014
• Refers: ASTM A904-14 - Standard Specification for 50 Nickel-50 Iron Powder Metallurgy Soft Magnetic Parts
• Effective Date: 01-May-2014
• Refers: ASTM A34/A34M-06(2012) - Standard Practice for Sampling and Procurement Testing of Magnetic Materials
• Effective Date: 01-Nov-2012
• Refers: ASTM A341/A341M-00(2011)e1 - Standard Test Method for Direct Current Magnetic Properties of Materials Using D-C Permeameters and the Ballistic Test Methods
• Effective Date: 01-Oct-2011
• Refers: ASTM A341/A341M-00(2011) - Standard Test Method for Direct Current Magnetic Properties of Materials Using D-C Permeameters and the Ballistic Test Methods
• Effective Date: 01-Oct-2011

Overview

ASTM A848-17: Standard Specification for Low-Carbon Magnetic Iron defines the requirements for wrought, low-carbon iron alloys used primarily in direct current (dc) magnetic applications. These iron materials feature a maximum carbon content of 0.015%, with the remainder chiefly iron, and are supplied in mill forms including forging billet, bar, wire, and strip. ASTM A848-17 establishes chemical and magnetic properties critical to reliable performance in magnetically sensitive applications, specifically omitting iron powders and flat-rolled electrical steels, which are covered by other standards. Both low-phosphorus (Type 1) and phosphorus-enhanced (Type 2, for improved machinability) grades are included, meeting specific coercive field strength requirements after heat treatment.

Key Topics

• Material Types Covered:

  • Type 1: Low-phosphorus grade for standard dc magnetic applications.
  • Type 2: Phosphorus addition for enhanced machinability, while still suitable for magnetic uses.

• Product Forms:

  • Forging billet
  • Hot-rolled and cold-finished bars
  • Wire
  • Strip (including deep-draw quality)

• Chemical Composition:

  • Carbon max: 0.020%
  • Manganese, silicon, phosphorus, sulfur, chromium, nickel, vanadium, titanium, and aluminum are controlled for magnetic performance and material integrity.
  • Iron is the balance in both alloy types.

• Magnetic Properties:

  • Direct current coercive field strength (HcB) is the key performance attribute, categorized as:
    • Class 1: ≤ 0.75 Oe (60 A/m)
    • Class 2: ≤ 1.0 Oe (80 A/m)
    • Class 3: ≤ 1.5 Oe (120 A/m)
  • Coercivity measured after prescribed heat treatment using accepted physical testing methods.

• Heat Treatment:

  • Standardized procedures to achieve optimal magnetic characteristics, including options for atmosphere control (e.g., hydrogen, vacuum).

• Magnetic Aging:

  • Appendix guidance on minimizing performance changes due to trace carbon and nitrogen, including alloying practices and post-processing techniques.

Applications

Low-carbon magnetic iron conforming to ASTM A848-17 is widely used in components where specific magnetic properties are essential, including:

• Electromechanical Relays: Due to guaranteed low coercive field strength, ensuring reliable and predictable magnetic response.
• Magnetic Sensor Parts: Supplied as strip, bar, or wire for fabrication of sensor cores or shielding.
• Actuators and Solenoids: Where consistent permeability and minimal magnetic aging are required over time.
• General DC Magnetic Components: Such as cores for assembled magnetic circuits in instrumentation and control devices.

Manufacturers and designers select ASTM A848-17 material forms for processes that include machining, forming, blanking, or deep drawing, with detailed ordering information ensuring delivery of the right condition and performance level.

Related Standards

ASTM A848-17 is part of a wider family of magnetic material standards. Relevant related standards include:

• ASTM A726 - Cold-Rolled Magnetic Lamination Quality Steel, Semiprocessed Types (for electrical steels)
• ASTM A811 - Soft Magnetic Iron Parts Fabricated by Powder Metallurgy Techniques
• ASTM A839 - Iron-Phosphorus Powder Metallurgy Parts for Soft Magnetic Applications
• ASTM A904 - 50 Nickel-50 Iron Powder Metallurgy Soft Magnetic Parts
• ASTM A34/A34M - Practice for Sampling and Procurement Testing of Magnetic Materials
• ASTM A340 - Terminology of Symbols and Definitions Relating to Magnetic Testing
• ASTM A341/A341M, A596/A596M, A773/A773M - Magnetic test methods for measuring dc properties
• IEC 60404-7 - Measurement of Coercivity of Magnetic Materials

ASTM A848-17 ensures the consistent quality and suitability of low-carbon magnetic iron for precision dc magnetic applications, supporting the needs of the electrical, instrumentation, and materials engineering sectors.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation:A848 −17
Standard Specification for
Low-Carbon Magnetic Iron
This standard is issued under the fixed designation A848; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
1.1 This specification covers the requirements for wrought
low-carbon iron typically having a carbon content of 0.015%
2. Referenced Documents
or less with the remainder of the chemical composition being
substantially iron.
2.1 ASTM Standards:
1.1.1 Two alloy types are covered: Type 1 is a low-
A34/A34MPractice for Sampling and Procurement Testing
phosphorousgradeandType2containsaphosphorousaddition
of Magnetic Materials
to improve machinability.
A340Terminology of Symbols and Definitions Relating to
1.2 This specification also covers alloys supplied by a Magnetic Testing
producer or converter in the form and condition suitable for
A341/A341MTest Method for Direct Current Magnetic
fabricationintopartswhichwillbesubsequentlyheattreatedto
Properties of Soft Magnetic Materials Using D-C Per-
create the desired magnetic characteristics. It covers alloys
meametersandthePointbyPoint(Ballistic)TestMethods
supplied in the form of forging billets, hot-rolled products, and
A596/A596MTest Method for Direct-Current Magnetic
cold-finished bar, wire, and strip.
Properties of Materials Using the Ballistic Method and
Ring Specimens
1.3 This specification does not cover iron powders capable
A726Specification for Cold-Rolled Magnetic Lamination
of being processed into magnetic components. Please refer to
Quality Steel, Semiprocessed Types
the following ASTM Standards for information regarding
A773/A773MTest Method for Direct Current Magnetic
powdered metal materials and magnetic components: Specifi-
Properties of Low Coercivity Magnetic Materials Using
cations A811, A839, and A904.
Hysteresigraphs
1.4 This specification does not cover flat-rolled, low-carbon
A811Specification for Soft Magnetic Iron Parts Fabricated
electrical steels. Please refer to Specification A726 for infor-
by Powder Metallurgy Techniques
mation regarding these materials.
A839Specification for Iron-Phosphorus Powder Metallurgy
1.5 The values stated in SI units are to be regarded as
Parts for Soft Magnetic Applications
standard. The values given in parentheses are mathematical
A904Specification for 50 Nickel-50 Iron Powder Metal-
conversions to customary (cgs-emu and inch-pound) units
lurgy Soft Magnetic Parts
whichareprovidedforinformationonlyandarenotconsidered
2.2 Other:
standard.
IEC Publication 60404-7 Magnetic Materials – Part 7:
1.6 This standard does not purport to address all of the
Method of Measurement of the Coercivity of Magnetic
safety concerns, if any, associated with its use. It is the
Materials in an Open Magnetic Circuit
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica-
3. Terminology
bility of regulatory limitations prior to use.
1.7 This international standard was developed in accor-
3.1 The terms and symbols used in this specification, unless
dance with internationally recognized principles on standard-
otherwise noted, are defined in Terminology A340.
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
This specification is under the jurisdiction of ASTM Committee A06 on contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Magnetic Properties and is the direct responsibility of Subcommittee A06.02 on Standards volume information, refer to the standard’s Document Summary page on
Material Specifications. the ASTM website.
Current edition approved April 1, 2017. Published May 2017. Originally Available from International Electrotechnical Commission (IEC), 3, rue de
approved in 1985. Last previous edition approved in 2011 as A848–01 (2011). Varembé, 1st Floor, P.O. Box 131, CH-1211, Geneva 20, Switzerland, http://
DOI: 10.1520/A0848-17. www.iec.ch.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
A848−17
4. Ordering Information 6.1.3.1 Relay condition applies to round bars of 25.4 mm
(1.00 in.) or less in diameter and other special shapes supplied
4.1 Orders to this specification shall include as much of the
in the cold-worked condition having up to 25% reduction in
following information as is required to describe the desired
area and capable of meeting Class 2 magnetic property
material:
requirements as defined in 7.5.
4.1.1 ASTM specification number and alloy type.
6.1.4 Strip—Cold rolled, cold rolled and annealed, deep
4.1.2 Dimensions and Tolerances—Dimensional tolerances
draw quality, mechanical properties as specified; or relay
are to be mutually agreed upon between the user and the
condition.
producer.
6.1.4.1 Relay condition applies to cold-rolled strip 0.51 to
4.1.3 Quantity (weight or number of pieces).
5.1 mm (0.020 to 0.20 in.) thick having up to 25% reduction
4.1.4 Form and condition.
in thickness and capable of meeting Class 2 magnetic property
4.1.5 Magnetic property requirements if they are other than
requirements as defined in 7.5 and Table 2.
stated herein.
6.1.4.2 Ordering information for strip must include edge
4.1.6 Certification of chemical analysis or magnetic prop-
condition and mechanical property requirements.
erty evaluation, or both.
6.1.5 Wire—Colddrawn,annealed,mechanicalpropertiesas
4.1.7 Marking and packaging.
specified or relay condition.
4.1.8 End Use—Whenever possible, the user should specify
6.1.5.1 Relay condition applies to cold-drawn wire when
whethertheproductwillbemachined,blankedintoflatpieces,
capable of being supplied having up to 25% reduction in area
blanked and formed, or deep drawn to shape.This information
and capable of meeting Class 2 magnetic property require-
willhelptheproducerprovidethemostsuitableproductforthe
ments as defined in 7.5 and Table 2.
user’s fabrication practice.
4.1.9 Exceptions to this specification or special require-
7. Magnetic Property Requirements
ments.
7.1 Density—The density for test purposes is
3 3
5. Chemical Composition
7.86g⁄cm (7860 kg/m ).
5.1 Alloyssuppliedtothisspecificationshallconformtothe
7.2 Test Specimen—The test specimen size and shape shall
alloy percentage requirements in Table 1. Vanadium, titanium, conform to Practice A34/A34M. Shapes such as ring
and aluminum are not required but may be added to suppress
laminations, solid rings, Epstein specimens, or straight lengths
magnetic aging; if present, they shall be analyzed and reported having a uniform cross section are preferred. If, however, it is
and shall meet the requirements in Table 1.
impossible to prepare a preferred test specimen shape from the
as-manufactured product, specimen shape and size shall be
6. Form and Condition
mutually agreed upon by the user and the producer.
6.1 The two alloy types are capable of being produced in a
7.3 Heat Treatment—It is recommended that the user
wide variety of forms and conditions for fabrication into
specify the desired heat treatment method to be applied to the
magneticcomponents.Thedesiredformandconditionshallbe
test specimens.
discussed with the producer to assure receiving the correct
7.3.1 When “relay condition” is specified, the test specimen
product. Available forms and conditions are:
shall be heat treated in a dry forming gas atmosphere (5 to
6.1.1 Forging Billet—Hot worked and surface conditioned
15% hydrogen in nitrogen with a dew point less than−40°C
by grinding.
(–40°F)) at a temperature of 845°C (1550°F) for one hour at
6.1.2 Hot-Rolled Product—Hot rolled; hot rolled and acid
temperatureandcooledataratefrom55to100°Cperhour(99
cleaned;hotrolledandannealed;hotrolled,annealed,andacid
to 180°F per hour) to 500°C (930°F) and cooled at any rate
cleaned; hot rolled and mechanically cleaned; mechanical
thereafter.
properties as specified.
7.3.2 If “relay condition” is not specified and no heat-
6.1.3 Cold-Finished Bars—Cold drawn, centerless ground,
treating procedure is specified by the user, the producer is free
mechanical properties as specified; or relay condition.
to choose a heat treatment procedure. Refer to Appendix X3
for heat treatment recommendations.
7.4 Test Method—Magnetic testing shall be conducted in
accordance with Test Methods A341/A341M, A596/A596M,
TABLE 1 Chemical Composition Requirements (Weight Percent)
or A773/A773M, or by use of a coercimeter as described in
Alloy Type 1 Alloy Type 2
7.5.1. Under this specification only the coercive field strength
Carbon, max 0.020 0.020
Manganese, max 0.35 0.35
(H ) must be measured.
cB
Silicon, max 0.15 0.15
Phosphorous 0.030 max 0.10 to 0.18
Sulfur, max 0.025 0.025
Chromium, max 0.20 0.20
Nickel, max 0.15 0.15
TABLE 2 Maximum Direct Current Coercive Field Strength, H
cB
Vanadium, max 0.10 0.10
Titanium, max 0.10 0.10 Class 1 60 A/m (0.75 Oe)
Aluminum, max 0.10 0.10 Class 2 (Relay Co
...

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: A848 − 01 (Reapproved 2011) A848 − 17
Standard Specification for
Low-Carbon Magnetic Iron
This standard is issued under the fixed designation A848; 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 the requirements for wrought low-carbon iron typically having a carbon content of 0.015 % or less
with the remainder of the analysis chemical composition 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. Please refer to the
following ASTM Standards for information regarding powdered metal materials and magnetic components: Specifications A811,
A839, and A904.
1.4 This specification does not cover flat-rolled, low-carbon electrical steels. Please refer to Specification A726 for information
regarding these materials.
1.5 The values stated in customary (cgs-emu and inch-pound) SI units are to be regarded as standard. The values given in
parentheses are mathematical conversions to SI customary (cgs-emu and inch-pound) units which are provided for information
only and are not considered standard.
1.6 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.
1.7 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
A34/A34M Practice for Sampling and Procurement Testing of Magnetic Materials
A340 Terminology of Symbols and Definitions Relating to Magnetic Testing
A341/A341M Test Method for Direct Current Magnetic Properties of Soft Magnetic Materials Using D-C Permeameters and the
Point by Point (Ballistic) Test Methods
A596/A596M Test Method for Direct-Current Magnetic Properties of Materials Using the Ballistic Method and Ring Specimens
A726 Specification for Cold-Rolled Magnetic Lamination Quality Steel, Semiprocessed Types
A773/A773M Test Method for Direct Current Magnetic Properties of Low Coercivity Magnetic Materials Using Hysteresig-
raphs
A811 Specification for Soft Magnetic Iron Parts Fabricated by Powder Metallurgy Techniques
A839 Specification for Iron-Phosphorus Powder Metallurgy Parts for Soft Magnetic Applications
A904 Specification for 50 Nickel-50 Iron Powder Metallurgy Soft Magnetic Parts
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, 2011April 1, 2017. Published May 2011May 2017. Originally approved in 1985. Last previous edition approved in 20062011 as
A848 – 01 (2011). (2006). DOI: 10.1520/A0848-01R11.10.1520/A0848-17.
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
A848 − 17
2.2 Other:
IEC Publication 60404-7 Ed. 1 Magnetic Materials – Part 7: Method of Measurement of the Coercivity of Magnetic Materials
in an Open Magnetic Circuit
3. Terminology
3.1 The terms and symbols used in this specification, unless otherwise noted, are defined in Terminology A340.
4. Ordering Information
4.1 Orders to this specification shall include as much of the following information as is required to describe the desired material:
4.1.1 ASTM specification number and alloy type.
4.1.2 Dimensions and Tolerances—TheDimensional tolerances are to be mutually agreed upon between the user and the
producer.
4.1.3 Quantity (weight or number of pieces).
4.1.4 Form and condition.
4.1.5 Magnetic property requirements if they are other than stated herein.
4.1.6 Certification of chemical analysis or magnetic property evaluation, or both.
4.1.7 Marking and packaging.
4.1.8 End Use—Whenever possible, the user should specify whether the product will be machined, blanked into flat pieces,
blanked and formed, or deep drawn to shape. This information will help the producer provide the most suitable product for the
user’s fabrication practice.
4.1.9 Exceptions to this specification or special requirements.
5. Chemical Composition
5.1 Alloys supplied to this specification shall conform to the alloy percentage requirements in Table 1. Three of the elements
listed in Vanadium, Table 1, namely vanadium, titanium, and aluminum,aluminum are not required but may be added to suppress
magnetic aging. Ifaging; if present, they mustshall be analyzed and reported.reported and shall meet the requirements in Table 1.
6. Form and Condition
6.1 TheseThe two alloys alloy types are capable of being produced in a wide variety of forms and conditions for fabrication
into magnetic components. The desired form and condition shall be discussed with the producer to assure receiving the correct
product. Available forms and conditions are:
6.1.1 Forging Billet—Hot worked and surface conditioned by grinding.
6.1.2 Hot-Rolled Product—Hot rolled; hot rolled and acid cleaned; hot rolled and annealed; hot rolled, annealed, and acid
cleaned; hot rolled and mechanically cleaned; mechanical properties as specified.
6.1.3 Cold-Finished Bars—Cold drawn, centerless ground, mechanical properties as specified; or relay condition.
6.1.3.1 Relay condition applies to 1 in. (25.4 mm) round and Relay condition applies to round bars of 25.4 mm (1.00 in.) or
less in diameter and certain other special shapes supplied in the cold-worked condition having up to 25 % reduction in area and
capable of meeting Class 2 magnetic property requirements as defined in 6.57.5.
6.1.4 Strip—Cold rolled, cold rolled and annealed, deep draw quality, mechanical properties as specified; or relay condition.
6.1.4.1 Relay condition Relay condition applies to cold-rolled strip 0.020 to 0.200 in. (0.51 to 5.1 mm)0.51 to 5.1 mm (0.020
to 0.20 in.) thick having up to 25 % reduction in thickness and capable of meeting Class 2 magnetic property requirements as
defined in 6.57.5 and Table 2.
Available from American National Standards Institute, 25 W. 43rd St., 4th Floor, New York, NY 10036.International Electrotechnical Commission (IEC), 3, rue de
Varembé, 1st Floor, P.O. Box 131, CH-1211, Geneva 20, Switzerland, http://www.iec.ch.
TABLE 1 Chemical Composition Requirements (Weight Percent)
Alloy Type 1 Alloy Type 2
Carbon, max 0.020 0.020
Manganese, max 0.35 0.35
Silicon, max 0.15 0.15
Phosphorous 0.030 max 0.10/0.18
Phosphorous 0.030 max 0.10 to 0.18
Sulfur, max 0.025 0.025
Chromium, max 0.20 0.20
Nickel, max 0.15 0.15
Vanadium, max 0.10 0.10
Titanium, max 0.10 0.10
Aluminum, max 0.10 0.10
Iron balance balance
A848 − 17
TABLE 2 Direct Current Coercive Field Strength Requirements
Class 1 0.75 Oe (60 A/m)
Class 2 (Relay Condition) 1.0 Oe (80 A/m)
Class 3 1.5 Oe (120 A/m)
TABLE 2 Maximum Direct Current Coercive Field Strength, H
cB
Class 1 60 A/m (0.75 Oe)
Class 2 (Relay Condition) 80 A/m (1.0 Oe)
Class 3 120 A/m (1.5 Oe)
6.1.4.2 Ordering information for strip must include edge condition and mechanical property requirements.
6.1.5 Wire—Cold drawn, annealed, mechanical properties as specified or relay condition.
6.1.5.1 Relay condition applies to cold-drawn wire when capable of being supplied having up to 25 % reduction in area and
capable of meeting Class 2 magnetic property requirements as defined in 6.57.5 and Table 2.
7. Magnetic Property Requirements
3 3
7.1 Density—The density for test purposes is 7.86 g ⁄cm (7860 kg/m ).
7.2 Test Specimen—Whenever possible, The test specimen size and shape shall conform to Practice A34/A34M. Shapes such
as ring laminations, solid rings, Epstein specimens, or straight lengths having a uniform cross section are preferred. If, however,
it is impossible to prepare a preferred test specimen shape from the as-manufactured product, specimen shape and size shall be
mutually agreed upon by the user and the producer.
7.3 Heat Treatment—It is recommended that the user specify the desired heat treatment method to be applied to the test
specimens.
7.3.1 When relay condition“relay condition” is specified, the test specimen shall be heat treated in a dry forming gas atmosphere
(5 to 15 % hydrogen in nitrogen with a dew point less than −40°C) than −40°C (–40°F)) at a temperature of 845°C (1550°F) for
1 hone hour at temperature and cooled at a rate from 55 to 100°C/h to 500°C 100°C per hour (99 to 180°F per hour) to 500°C
(930°F) and cooled at any rate thereafter.
7.3.2 If relay condition“relay condition” is not specified and no heat-treating procedure is specified by the user, the producer
is free to choose a heat treatment procedure. Refer to Appendix X3 for heat treatment recommendations.
7.4 Test Method—Magnetic testing shall be conducted in accordance with Test Methods A341/A341M, A596/A596M, or
A773/A773M, or by use of a coercimeter. coercimeter as described in 7.5.1. Under this specification only the
...