1、Designation: A876 171Standard Specification forFlat-Rolled, Grain-Oriented, Silicon-Iron, Electrical Steel,Fully Processed Types1This standard is issued under the fixed designation A876; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisi
2、on, 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.1NOTEEditorially corrected units in Note B of Table X1.1 in July 2017.1. Scope1.1 This specification covers the de
3、tailed requirements towhich the specified grades of flat-rolled, grain-oriented, fullyprocessed electrical steels shall conform. These steels are usedprimarily in transformer cores operating at moderate to highmagnetic flux densities at commercial power frequencies (50and 60 Hz).1.2 These grain-orie
4、nted electrical steels are low-carbon,silicon-iron alloys with a silicon content of approximately3.2 % in which low core loss and high permeability in thedirection of rolling have been achieved by appropriate metal-lurgical processing.1.3 The electrical-steel grades described in this specificationin
5、clude (1) conventional grain-oriented electrical steel tested at1.5 T (15 kG) in accordance with Test Method A343/A343M,(2) conventional grain-oriented electrical steel tested at 1.7 T(17 kG) in accordance with Test Method A343/A343M,(3)high-permeability grain-oriented electrical steel tested at 1.7
6、 T(17 kG) in accordance with Test Method A343/A343M, and (4)laser-scribed high-permeability grain-oriented electrical steeltested at 1.7 T (17 kG) in accordance with Test MethodsA804/A804M.1.4 The values stated in SI units are to be regarded asstandard. The values given in parentheses are mathematic
7、alconversions to customary (cgs-emu and inch-pound) unitswhich 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
8、appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.1.6 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of
9、 International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2A34/A34M Practice for Sampling and Procurement Testingof Magnetic MaterialsA340 Terminology of Symbols and Definitions Re
10、lating toMagnetic TestingA343/A343M Test Method for Alternating-Current Mag-netic Properties of Materials at Power Frequencies UsingWattmeter-Ammeter-Voltmeter Method and 25-cm Ep-stein Test FrameA345 Specification for Flat-Rolled Electrical Steels forMagnetic ApplicationsA664 Practice for Identific
11、ation of Standard Electrical SteelGrades in ASTM SpecificationsA700 Guide for Packaging, Marking, and Loading Methodsfor Steel Products for ShipmentA717/A717M Test Method for Surface Insulation Resistivityof Single-Strip SpecimensA719/A719M Test Method for Lamination Factor of Mag-netic MaterialsA72
12、1/A721M Test Method for Ductility of Oriented Electri-cal SteelA804/A804M Test Methods for Alternating-Current Mag-netic Properties of Materials at Power Frequencies UsingSheet-Type Test SpecimensA937/A937M Test Method for Determining InterlaminarResistance of Insulating Coatings Using Two AdjacentT
13、est SurfacesA976 Classification of Insulating Coatings for Electrical1This specification is under the jurisdiction of ASTM Committee A06 onMagnetic Properties and is the direct responsibility of Subcommittee A06.02 onMaterial Specifications.This specification replaces A665, A725, and A843.Current ed
14、ition approved April 1, 2017. Published May 2017. Originallyapproved in 1987. Last previous edition approved in 2012 as A876 12. DOI:10.1520/A0876-17E01.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMSt
15、andards 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 StatesThis international standard was developed in accordance with internationally recognized princip
16、les on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1Steels by Composition, Relative Insulating Ability andApplication3. Terminolo
17、gy3.1 The terms and symbols used in this specification aredefined in Terminology A340.4. Classification4.1 The ASTM core-loss type designations, formulated inaccordance with Practice A664, for grain-oriented electricalsteels covered by this specification are listed in Table 1.5. Condition5.1 These g
18、rain-oriented electrical steels may be purchasedin any of the following conditions (which are combinations ofmaterial form and surface type or treatment) as desired for theexpected end use.5.1.1 Condition NFAn annealed coil form having aninorganic surface coating, Type C-2 (Note 1). This material is
19、not flattened and so exhibits appreciable coil curvature. Theprincipal application is in spirally wound or formed cores inwhich the strip curvature is not detrimental to fabricatingprocedures or device performance.5.1.2 Condition F2Thermally flattened sheet or coiledstrip having an inorganic surface
20、 coating, Type C-2, plus athinner (compared to Condition F5) inorganic coating, TypeC-5, applied over the inherent C-2 coating. The principalapplication is in spirally wound or formed cores in which stripcurvature is not detrimental to fabricating procedures or deviceperformance.5.1.3 Condition F5Th
21、ermally flattened sheet or coiledstrip having an inorganic surface coating, Type C-2, plus aninorganic coating, Type C-5, applied over the inherent C-2coating to provide extra surface insulation resistance. Theprincipal application is in flat sheared laminations for cores ofpower transformers.5.1.4
22、Condition PQThermally flattened sheet or coiledstrip (sometimes called “punching quality”) with the inherentC-2 coating removed and an inorganic coating, Type C-5,applied for insulative purposes. The principal application is inflat stamped laminations for small stacked cores with onlymoderate surfac
23、e insulation requirements.NOTE 1Additional description of surface coating Types C-2 and C-5is presented in Specification A345 and Classification A976.5.2 Core-loss types having code letters Pand Q are availableonly in Condition F5.6. Ordering Information6.1 Orders for material under this specificati
24、on shall includesuch of the following information as is required to describe thematerial adequately:6.1.1 ASTM specification number,TABLE 1 Core-Loss Type DesignationsConventional Grain-Oriented Electrical SteelTested at 1.5 T (15 kG) in Accordance with Test Method A343/A343MASTMCore-LossTypeAAimThi
25、ckness,Bmm (in.)Maximum Specific CoreLoss,CW/kg (W/lb)60 Hz 50 Hz18G041 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 Gr
26、ain-Oriented Electrical SteelTested at 1.7 T (17 kG) in Accordance with Test Method A343/A343MASTMCore-LossTypeAAimThickness,Bmm (in.)Maximum Specific CoreLoss,CW/kg (W/lb)60 Hz 50 Hz23H070 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.
27、83) 1.39 (0.63)35H094 0.35 (0.0138) 2.07 (0.94) 1.57 (0.71)High-Permeability Grain-Oriented Electrical SteelTested at 1.7 T (17 kG) in Accordance with Test Method A343/A343MASTMCore-LossTypeAAimThickness,Bmm (in.)Maximum Specific CoreLoss,CW/kg (W/lb)60 Hz 50 Hz23P060 0.23 (0.0090) 1.32 (0.60) 1.01
28、(0.46)27P066 0.27 (0.0106) 1.46 (0.66) 1.11 (0.50)Laser-Scribed High-Permeability Grain-Oriented Electrical SteelTested at 1.7 T (17 kG) in Accordance with Test Methods A804/A804MASTMCore-LossTypeAAimThickness,Bmm (in.)Maximum Specific CoreLoss,DW/kg (W/lb)60 Hz 50 Hz23Q054 0.23 (0.0090) 1.19 (0.54)
29、 0.90 (0.41)27Q057 0.27 (0.0106) 1.26 (0.57) 0.96 (0.43)ASee Practice A664.BThese shall be the overall thicknesses as measured by contacting micrometre caliper.CBased on parallel-grain Epstein specimens, stress-relief annealed after shearing in accordance with 14.1.2.DBased on as-sheared parallel-gr
30、ain sheet-type specimens. Stress-relief annealing will nullify the core-loss reduction produced by the laser scribing.A876 17126.1.2 ASTM core-loss type designation (Table 1),6.1.3 Material condition (form and surface type) designa-tion (5.1),6.1.4 Ductility class (when required),6.1.5 Sheet or stri
31、p width,6.1.6 Length (only when cut lengths are specified),6.1.7 Total weight of each ordered item,6.1.8 Limitations on lift weight,6.1.9 Limitations on coil size,6.1.10 End Use(Whenever practicable, the user shouldspecify whether the ordered material will be made into flatsheared laminations, flat
32、stamped laminations, wound cores,bonded wound cores, formed lamination cores, welded lami-nation cores, and so forth. This will help the producer toprovide the most suitable material for the users fabricatingpractices), and6.1.11 Exception to the specification or special require-ments.7. Materials a
33、nd Manufacture7.1 Normally, these steels contain approximately 3.2 %silicon and the balance iron with residual elements at aminimum. When requested, the producer shall provide astatement of chemical composition typical of the materialbeing supplied.7.2 These electrical steels may be made by the basi
34、c-oxygenor electric-furnace process.7.3 When changes in the manufacture of successive ship-ments of the material are believed to increase the likelihood ofadverse effects upon the magnetic performance or fabricationfor the specified end use, the producer shall notify the user assoon as possible befo
35、re shipment is made so that he can beafforded an opportunity to evaluate the effects.8. Magnetic Properties8.1 Core Loss:8.1.1 Maximum permissible specific core losses at 1.5 or1.7T(15 or 17 kG), 50 and 60 Hz, are guaranteed and are listedin Table 1 for the ASTM core-loss types. The sampling,specime
36、n preparation, and testing practices that are describedherein must be followed when conformity to these guaranteesis being checked.8.1.2 Material that conforms to both the core-loss andthickness limits of this specification shall be identified by thisspecification number and the appropriate core-los
37、s designation.8.2 Permeability:8.2.1 The permeability at all magnetic flux densities shall beas high as practicable. The quality control of these grades isnormally based on a measurement of relative peakpermeability, p, at a peak ac magnetic field strength, Hp,of796 A/m (10 Oe). For the conventional
38、 grain-oriented grades,the value of relative pat 796A/m (10 Oe) is commonly above1800. For the high-permeability grades, it is commonly above1880.8.3 Magnetic Aging: Although the magnetic properties ofthese electrical steels are considered to be stable, the maximumcore-loss values of Table 1 are bas
39、ed on tests of non-agedspecimens. The guarantee of magnetic properties after an agingtreatment is subject to negotiation between the user and theproducer.9. Surface Insulation Characteristics9.1 The surfaces types produced in each of the materialconditions of 5.1 normally have different levels of in
40、sulatingability. Interlaminar resistance of two adjacent test surfaces isdetermined withTest Method A937/A937M. Surface insulationresistivity of a single test surface is determined with TestMethod A717/A717M. Typical ranges for surface insulationeffectiveness of the various surface types are given i
41、n Appen-dix X1.9.2 When insulative characteristics substantially differentthan those listed in Appendix X1 are necessary, the specificrequirements and the procedures for evaluating them shall benegotiated between the user and the producer.10. Physical and Mechanical Properties10.1 Lamination FactorT
42、he lamination factor shall be ashigh as practicable consistent with the material thickness andcondition. Lamination factor may be determined using TestMethod A719/A719M. Typical lamination factor values for thevarious material thickness and condition combinations areshown in Appendix X1.10.2 Ductili
43、tyThe ductility shall be as high as practicable.When the application requires forming around a sharp radiusduring fabrication, and an evaluation of the ductility isrequired, the ductility rating shall be determined in accordancewith Test Method A721/A721M. Ductility ratings in thefollowing classes a
44、re appropriate for grain-oriented steels inany thickness and condition when tested at room temperaturewith a bend transverse to the rolling direction with “as-sheared” specimens:Ductility Class Permissible Number of Fractures at BendA1 none2 1 or 2, total length not over 12.7 mm (0.5 in.)3 3 to 8ABa
45、sed on 610 to 910 mm (24- to 36-in.) width of material. For widths less than610 mm (24 in.), the number of permissible fractures should be reduced inproportion to the ratio of the width to 610 mm (24 in.).11. Dimensions and Permissible Variations11.1 ThicknessThe aim thicknesses of the ASTM core-los
46、s types are listed in Table 1.11.1.1 Thickness VariationsThe thickness measured atany location not less than 10 mm (0.4 in.) from an edge shallnot deviate more than 60.025 mm (60.001 in.) from theaverage thickness of the test lot or coil. The outer limits ofacceptable thickness of the ASTM core-loss
47、 type shall be asshown in Table 2.11.2 Width TolerancesThe width of material supplied,either as coils or cut lengths, shall be as close as possible to theordered width, but in no case shall the maximum deviationsfrom the specified width exceed the values given in Table 3.A876 171311.3 Length Toleran
48、cesThe length dimension of cutlengths shall be as close as practicable to the ordered length.The maximum deviations from ordered length shall be asshown in Table 4.11.4 Camber (Full-Width Coils)The deviation of a sideedge from a straight line over a 2440-mm (96-in.) length orfraction thereof shall n
49、ot exceed 3.2 mm (0.125 in.).11.5 Out of Square (Cut Lengths)The deviation of an endedge from a straight line placed at a right angle to the side,touching one corner and extending to the other side, shall notexceed 1.6 mm/152 mm (0.0625 in./6 in.) of width or fractionthereof.12. Workmanship, Finish, and Appearance12.1 Flatness:12.1.1 Sharp, short waves and buckles are extremely detri-mental to the effective use of grain-oriented electrical steels inflat laminations and shall be avoided in the delivered product.12.1.2 The user shall inform the producer of any
