ASTM A876-17e1

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.
´1
Designation:A876 −17
Standard Specification for
Flat-Rolled, Grain-Oriented, Silicon-Iron, Electrical Steel,
Fully Processed Types
This standard is issued under the fixed designation A876; 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.
ε NOTE—Editorially corrected units in Note B of Table X1.1 in July 2017.
1. Scope 1.6 This international standard was developed in accor-
dance with internationally recognized principles on standard-
1.1 This specification covers the detailed requirements to
ization established in the Decision on Principles for the
which the specified grades of flat-rolled, grain-oriented, fully
Development of International Standards, Guides and Recom-
processed electrical steels shall conform.These steels are used
mendations issued by the World Trade Organization Technical
primarily in transformer cores operating at moderate to high
Barriers to Trade (TBT) Committee.
magnetic flux densities at commercial power frequencies (50
and 60 Hz).
2. Referenced Documents
1.2 These grain-oriented electrical steels are low-carbon,
2.1 ASTM Standards:
silicon-iron alloys with a silicon content of approximately
A34/A34MPractice for Sampling and Procurement Testing
3.2% in which low core loss and high permeability in the
of Magnetic Materials
direction of rolling have been achieved by appropriate metal-
A340Terminology of Symbols and Definitions Relating to
lurgical processing.
Magnetic Testing
1.3 Theelectrical-steelgradesdescribedinthisspecification
A343/A343MTest Method for Alternating-Current Mag-
include(1)conventionalgrain-orientedelectricalsteeltestedat
netic Properties of Materials at Power Frequencies Using
1.5 T (15 kG) in accordance with Test Method A343/A343M,
Wattmeter-Ammeter-Voltmeter Method and 25-cm Ep-
(2) conventional grain-oriented electrical steel tested at 1.7 T
stein Test Frame
(17 kG) in accordance with Test Method A343/A343M,(3)
A345Specification for Flat-Rolled Electrical Steels for
high-permeability grain-oriented electrical steel tested at 1.7 T
Magnetic Applications
(17kG)inaccordancewithTestMethodA343/A343M,and(4)
A664Practice for Identification of Standard Electrical Steel
laser-scribed high-permeability grain-oriented electrical steel
Grades in ASTM Specifications
tested at 1.7 T (17 kG) in accordance with Test Methods
A700Guide for Packaging, Marking, and Loading Methods
A804/A804M.
for Steel Products for Shipment
A717/A717MTestMethodforSurfaceInsulationResistivity
1.4 The values stated in SI units are to be regarded as
of Single-Strip Specimens
standard. The values given in parentheses are mathematical
A719/A719MTest Method for Lamination Factor of Mag-
conversions to customary (cgs-emu and inch-pound) units
netic Materials
whichareprovidedforinformationonlyandarenotconsidered
A721/A721MTest Method for Ductility of Oriented Electri-
standard.
cal Steel
1.5 This standard does not purport to address all of the
A804/A804MTest Methods for Alternating-Current Mag-
safety concerns, if any, associated with its use. It is the
netic Properties of Materials at Power Frequencies Using
responsibility of the user of this standard to establish appro-
Sheet-Type Test Specimens
priate safety and health practices and determine the applica-
A937/A937MTest Method for Determining Interlaminar
bility of regulatory limitations prior to use.
Resistance of Insulating Coatings Using Two Adjacent
Test Surfaces
A976Classification of Insulating Coatings for Electrical
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.
This specification replaces A665, A725, and A843. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved April 1, 2017. Published May 2017. Originally contactASTM Customer Service at service@astm.org. ForAnnual Book ofASTM
approved in 1987. Last previous edition approved in 2012 as A876–12. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/A0876-17E01. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
´1
A876−17
Steels by Composition, Relative Insulating Ability and C-5, applied over the inherent C-2 coating. The principal
Application application is in spirally wound or formed cores in which strip
curvatureisnotdetrimentaltofabricatingproceduresordevice
3. Terminology
performance.
5.1.3 Condition F5—Thermally flattened sheet or coiled
3.1 The terms and symbols used in this specification are
strip having an inorganic surface coating, Type C-2, plus an
defined in Terminology A340.
inorganic coating, Type C-5, applied over the inherent C-2
4. Classification
coating to provide extra surface insulation resistance. The
principal application is in flat sheared laminations for cores of
4.1 The ASTM core-loss type designations, formulated in
power transformers.
accordance with Practice A664, for grain-oriented electrical
5.1.4 Condition PQ—Thermally flattened sheet or coiled
steels covered by this specification are listed in Table 1.
strip (sometimes called “punching quality”) with the inherent
C-2 coating removed and an inorganic coating, Type C-5,
5. Condition
applied for insulative purposes. The principal application is in
5.1 These grain-oriented electrical steels may be purchased
flat stamped laminations for small stacked cores with only
in any of the following conditions (which are combinations of
moderate surface insulation requirements.
material form and surface type or treatment) as desired for the
expected end use. NOTE 1—Additional description of surface coating Types C-2 and C-5
is presented in Specification A345 and Classification A976.
5.1.1 Condition NF—An annealed coil form having an
inorganic surface coating, Type C-2 (Note 1). This material is
5.2 Core-losstypeshavingcodelettersPandQareavailable
not flattened and so exhibits appreciable coil curvature. The
only in Condition F5.
principal application is in spirally wound or formed cores in
6. Ordering Information
which the strip curvature is not detrimental to fabricating
procedures or device performance. 6.1 Ordersformaterialunderthisspecificationshallinclude
5.1.2 Condition F2—Thermally flattened sheet or coiled suchofthefollowinginformationasisrequiredtodescribethe
strip having an inorganic surface coating, Type C-2, plus a material adequately:
thinner (compared to Condition F5) inorganic coating, Type 6.1.1 ASTM specification number,
TABLE 1 Core-Loss Type Designations
Conventional Grain-Oriented Electrical Steel
Tested at 1.5 T (15 kG) in Accordance with Test Method A343/A343M
ASTM Aim Maximum Specific Core
B C
Core-Loss Thickness, Loss, W/kg (W/lb)
A
mm (in.)
Type
60 Hz 50 Hz
18G041 0.18 (0.0070) 0.90 (0.41) 0.68 (0.31)
23G045 0.23 (0.0090) 0.99 (0.45) 0.75 (0.34)
27G051 0.27 (0.0106) 1.12 (0.51) 0.85 (0.39)
30G058 0.30 (0.0118) 1.28 (0.58) 0.97 (0.44)
35G066 0.35 (0.0138) 1.46 (0.66) 1.11 (0.50)
Conventional Grain-Oriented Electrical Steel
Tested at 1.7 T (17 kG) in Accordance with Test Method A343/A343M
ASTM Aim Maximum Specific Core
B C
Core-Loss Thickness, Loss, W/kg (W/lb)
A
mm (in.)
Type
60 Hz 50 Hz
23H070 0.23 (0.0090) 1.54 (0.70) 1.17 (0.53)
27H074 0.27 (0.0106) 1.63 (0.74) 1.24 (0.56)
30H083 0.30 (0.0118) 1.83 (0.83) 1.39 (0.63)
35H094 0.35 (0.0138) 2.07 (0.94) 1.57 (0.71)
High-Permeability Grain-Oriented Electrical Steel
Tested at 1.7 T (17 kG) in Accordance with Test Method A343/A343M
ASTM Aim Maximum Specific Core
B C
Core-Loss Thickness, Loss, W/kg (W/lb)
A
mm (in.)
Type
60 Hz 50 Hz
23P060 0.23 (0.0090) 1.32 (0.60) 1.01 (0.46)
27P066 0.27 (0.0106) 1.46 (0.66) 1.11 (0.50)
Laser-Scribed High-Permeability Grain-Oriented Electrical Steel
Tested at 1.7 T (17 kG) in Accordance with Test Methods A804/A804M
ASTM Aim Maximum Specific Core
B D
Core-Loss Thickness, Loss, W/kg (W/lb)
A
mm (in.)
Type 60 Hz 50 Hz
23Q054 0.23 (0.0090) 1.19 (0.54) 0.90 (0.41)
27Q057 0.27 (0.0106) 1.26 (0.57) 0.96 (0.43)
A
See Practice A664.
B
These shall be the overall thicknesses as measured by contacting micrometre caliper.
C
Based on parallel-grain Epstein specimens, stress-relief annealed after shearing in accordance with 14.1.2.
D
Based on as-sheared parallel-grain sheet-type specimens. Stress-relief annealing will nullify the core-loss reduction produced by the laser scribing.
´1
A876−17
6.1.2 ASTM core-loss type designation (Table 1), specimens.Theguaranteeofmagneticpropertiesafteranaging
6.1.3 Material condition (form and surface type) designa- treatment is subject to negotiation between the user and the
tion (5.1), producer.
6.1.4 Ductility class (when required),
6.1.5 Sheet or strip width,
9. Surface Insulation Characteristics
6.1.6 Length (only when cut lengths are specified),
9.1 The surfaces types produced in each of the material
6.1.7 Total weight of each ordered item,
conditions of 5.1 normally have different levels of insulating
6.1.8 Limitations on lift weight,
ability. Interlaminar resistance of two adjacent test surfaces is
6.1.9 Limitations on coil size,
determinedwithTestMethodA937/A937M.Surfaceinsulation
6.1.10 End Use—(Whenever practicable, the user should
resistivity of a single test surface is determined with Test
specify whether the ordered material will be made into flat
Method A717/A717M. Typical ranges for surface insulation
sheared laminations, flat stamped laminations, wound cores,
effectiveness of the various surface types are given in Appen-
bonded wound cores, formed lamination cores, welded lami-
dix X1.
nation cores, and so forth. This will help the producer to
provide the most suitable material for the user’s fabricating
9.2 When insulative characteristics substantially different
practices), and
than those listed in Appendix X1 are necessary, the specific
6.1.11 Exception to the specification or special require-
requirements and the procedures for evaluating them shall be
ments.
negotiated between the user and the producer.
7. Materials and Manufacture
10. Physical and Mechanical Properties
7.1 Normally, these steels contain approximately 3.2%
10.1 Lamination Factor—The lamination factor shall be as
silicon and the balance iron with residual elements at a
high as practicable consistent with the material thickness and
minimum. When requested, the producer shall provide a
condition. Lamination factor may be determined using Test
statement of chemical composition typical of the material
MethodA719/A719M.Typicallaminationfactorvaluesforthe
being supplied.
various material thickness and condition combinations are
7.2 Theseelectricalsteelsmaybemadebythebasic-oxygen
shown in Appendix X1.
or electric-furnace process.
10.2 Ductility—Theductilityshallbeashighaspracticable.
7.3 When changes in the manufacture of successive ship-
When the application requires forming around a sharp radius
ments of the material are believed to increase the likelihood of
during fabrication, and an evaluation of the ductility is
adverse effects upon the magnetic performance or fabrication
required, the ductility rating shall be determined in accordance
for the specified end use, the producer shall notify the user as
with Test Method A721/A721M. Ductility ratings in the
soon as possible before shipment is made so that he can be
following classes are appropriate for grain-oriented steels in
afforded an opportunity to evaluate the effects.
any thickness and condition when tested at room temperature
with a bend transverse to the rolling direction with “as-
8. Magnetic Properties
sheared” specimens:
8.1 Core Loss:
A
Ductility Class Permissible Number of Fractures at Bend
8.1.1 Maximum permissible specific core losses at 1.5 or
1 none
1.7T(15or17kG),50and60Hz,areguaranteedandarelisted
2 1 or 2, total length not over 12.7 mm (0.5 in.)
in Table 1 for the ASTM core-loss types. The sampling,
3 3 to 8
specimen preparation, and testing practices that are described
A
herein must be followed when conformity to these guarantees
Based on 610 to 910 mm (24- to 36-in.) width
...