1、Designation: A 876 09Standard Specification forFlat-Rolled, Grain-Oriented, Silicon-Iron, Electrical Steel,Fully Processed Types1This standard is issued under the fixed designation A 876; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revis
2、ion, 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.1. Scope1.1 This specification covers the detailed requirements towhich the specified grades of flat-rolled, grai
3、n-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-oriented electrical steels are low-carbon,silicon-iron alloys with a sili
4、con 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 specificationinclude (1) conventional grain-oriented electrical steel tested at15 kG
5、 (1.5 T) in accordance with Test MethodA 343/A 343M,(2) conventional grain-oriented electrical steel tested at 17 kG(1.7 T) in accordance with Test Method A 343/A 343M,(3)high-permeability grain-oriented electrical steel tested at 17 kG(1.7T) in accordance withTest MethodA 343/A 343M, and (4)laser-s
6、cribed high-permeability grain-oriented electrical steeltested at 17 kG (1.7 T) in accordance with Test MethodsA 804/A 804M.1.4 The values stated in customary (cgs-emu and inch-pound) units are to be regarded as standard. The values givenin parentheses are mathematical conversions to SI units, which
7、are provided for information only and are not consideredstandard.2. Referenced Documents2.1 ASTM Standards:2A 34/A 34M Practice for Sampling and Procurement Test-ing of Magnetic MaterialsA 340 Terminology of Symbols and Definitions Relating toMagnetic TestingA 343/A 343M Test Method for Alternating-
8、Current Mag-netic Properties of Materials at Power Frequencies UsingWattmeter-Ammeter-Voltmeter Method and 25-cm EpsteinTest FrameA 345 Specification for Flat-Rolled Electrical Steels forMagnetic ApplicationsA 664 Practice for Identification of Standard ElectricalSteel Grades in ASTM SpecificationsA
9、 700 Practices for Packaging, Marking, and LoadingMethods for Steel Products for ShipmentA 717/A 717M Test Method for Surface Insulation Resis-tivity of Single-Strip SpecimensA 719/A 719M Test Method for Lamination Factor of Mag-netic MaterialsA 721/A 721M Test Method for Ductility of Oriented Elec-
10、trical SteelA 804/A 804M Test Methods for Alternating-Current Mag-netic Properties of Materials at Power Frequencies UsingSheet-Type Test SpecimensA 937/A 937M Test Method for Determining InterlaminarResistance of Insulating Coatings Using Two AdjacentTest SurfacesA 976 Classification of Insulating
11、Coatings for ElectricalSteels by Composition, Relative Insulating Ability andApplication3. Terminology3.1 The terms and symbols used in this specification aredefined in Terminology A 340.4. Classification4.1 The ASTM core-loss type designations, formulated inaccordance with Practice A 664, for grain
12、-oriented electricalsteels covered by this specification are listed in Table 1.5. Condition5.1 These grain-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.1This spe
13、cification is under the jurisdiction of ASTM Committee A06 onMagnetic Properties and is the direct responsibility of Subcommittee A06.02 onMaterial Specifications.This specification replaces A 665, A 725, and A 843.Current edition approved May 1, 2009. Published June 2009. Originallyapproved in 1987
14、. Last previous edition approved in 2003 as A 87603.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyrigh
15、t ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.1.1 Condition NFAn annealed coil form having aninorganic surface coating, Type C-2 (Note 1). This material isnot flattened and so exhibits appreciable coil curvature. Theprincipal application
16、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 coating, Type C-2, plus athinner (compared to Condition F5) inorganic coating, Typ
17、eC-5, applied over the inherent C-2 coating. The principalapplication is in spirally wound or formed cores in which stripcurvature would be detrimental to fabricating procedures.5.1.3 Condition F5Thermally flattened sheet or coiledstrip having an inorganic surface coating, Type C-2, plus aninorganic
18、 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 Condition PQThermally flattened sheet or coiledstrip (sometimes called “punching quality”) with the in
19、herentC-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 surface insulation requirements.NOTE 1Additional description of surface coating Types C-2 and C-5is presente
20、d in Specification A 345 and Classification A 976.5.2 Core-loss types having code letters Pand Q are availableonly in Condition F5.6. Ordering Information6.1 Orders for material under this specification shall includesuch of the following information as is required to describe thematerial adequately:
21、6.1.1 ASTM specification number,6.1.2 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 strip width,6.1.6 Length (only when cut lengths are specified),6.1.7 Total weight of each ordered i
22、tem,6.1.8 Limitations on lift weight,6.1.9 Limitations on coil size,TABLE 1 Core-Loss Type DesignationsConventional Grain-Oriented Electrical SteelTested at 15 kG (1.5 T) in Accordance with Test Method A 343/A 343MASTMCore-LossTypeAAimThickness,Bin. (mm)Maximum Specific CoreLoss,CW/lb (W/kg)60 Hz 50
23、 Hz18G041 0.0070 (0.18) 0.41 (0.90) 0.31 (0.68)23G045 0.0090 (0.23) 0.45 (0.99) 0.34 (0.75)27G051 0.0106 (0.27) 0.51 (1.12) 0.39 (0.85)30G058 0.0118 (0.30) 0.58 (1.28) 0.44 (0.97)35G066 0.0138 (0.35) 0.66 (1.46) 0.50 (1.11)Conventional Grain-Oriented Electrical SteelTested at 17 kG (1.7 T) in Accord
24、ance with Test Method A 343/A 343MASTMCore-LossTypeAAimThickness,Bin. (mm)Maximum Specific CoreLoss,CW/lb (W/kg)60 Hz 50 Hz23H070 0.0090 (0.23) 0.70 (1.54) 0.53 (1.17)27H074 0.0106 (0.27) 0.74 (1.63) 0.56 (1.24)30H083 0.0118 (0.30) 0.83 (1.83) 0.63 (1.39)35H094 0.0138 (0.35) 0.94 (2.07) 0.71 (1.57)H
25、igh-Permeability Grain-Oriented Electrical SteelTested at 17 kG (1.7 T) in Accordance with Test Method A 343/A 343MASTMCore-LossTypeAAimThickness,Bin. (mm)Maximum Specific CoreLoss,CW/lb (W/kg)60 Hz 50 Hz23P060 0.0090 (0.23) 0.60 (1.32) 0.46 (1.01)27P066 0.0106 (0.27) 0.66 (1.46) 0.50 (1.11)Laser-Sc
26、ribed High-Permeability Grain-Oriented Electrical SteelTested at 17 kG (1.7 T) in Accordance with Test Methods A 804/A 804MASTMCore-LossTypeAAimThickness,Bin. (mm)Maximum Specific CoreLoss,DW/lb (W/kg)60 Hz 50 Hz23Q054 0.0090 (0.23) 0.54 (1.19) 0.41 (0.90)27Q057 0.0106 (0.27) 0.57 (1.26) 0.43 (0.96)
27、ASee Practice A 664.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-grain sheet-type specimens. Stress-relief annealing will
28、nullify the core-loss reduction produced by the laser scribing.A8760926.1.10 End Use(Whenever practicable, the user shouldspecify whether the ordered material will be made into flatsheared laminations, flat stamped laminations, wound cores,bonded wound cores, formed lamination cores, welded lami-nat
29、ion 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 and Manufacture7.1 Normally, these steels contain approximately 3.2 %silicon and the balance i
30、ron 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 basic-oxygenor electric-furnace process.7.3 When changes in the manufacture of successive ship-me
31、nts 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 before shipment is made so that he can beafforded an opportunity to evaluate the effects.8. Magne
32、tic Properties8.1 Core Loss:8.1.1 Maximum permissible specific core losses at 15 or 17kG (1.5 or 1.7 T), 50 and 60 Hz, are guaranteed and are listedin Table 1 for the ASTM core-loss types. The sampling,specimen preparation, and testing practices that are describedherein must be followed when conform
33、ity 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-loss designation.8.2 Permeability:8.2.1 The permeability at all magnetic flux densities shall
34、beas high as practicable. The quality control of these grades isnormally based on a measurement of relative peak permeabil-ity, p, at a peak ac magnetic field strength, Hp, of 10 Oe (796A/m). For the conventional grain-oriented grades, the value ofrelative pat 10 Oe (796 A/m) is commonly above 1800.
35、 Forthe high-permeability grades, it is commonly above 1880.8.3 Magnetic Aging:Although the magnetic properties of these electrical steelsare considered to be stable, the maximum core-loss values ofTable 1 are based on tests of non-aged specimens. Theguarantee of magnetic properties after an aging t
36、reatment issubject to negotiation between the user and the producer.9. Surface Insulation Characteristics9.1 The surfaces types produced in each of the materialconditions of 5.1 normally have different levels of insulatingability. Interlaminar resistance of two adjacent test surfaces isdetermined wi
37、th Test Method A 937/A 937M. Surface insula-tion resistivity of a single test surface is determined with TestMethod A 717/A 717M. Typical ranges for surface insulationeffectiveness of the various surface types are given in Appen-dix X1.9.2 When insulative characteristics substantially differentthan
38、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 FactorThe lamination factor shall be ashigh as practicable consistent with the materia
39、l thickness andcondition. Lamination factor may be determined using TestMethod A 719/A 719M. Typical lamination factor values forthe various material thickness and condition combinations areshown in Appendix X1.10.2 DuctilityThe ductility shall be as high as practicable.When the application requires
40、 forming around a sharp radiusduring fabrication, and an evaluation of the ductility is re-quired, the ductility rating shall be determined in accordancewith Test Method A 721/A 721M. Ductility ratings in thefollowing classes are appropriate for grain-oriented steels inany thickness and condition wh
41、en 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 0.5 in. (12.7 mm)3 3 to 8ABased on 24- to 36-in. (610- to 910-mm) width of material. For widths less
42、than24 in. (610 mm), the number of permissible fractures should be reduced inproportion to the ratio of the width to 24 in. (610 mm).11. Dimensions and Permissible Variations11.1 ThicknessThe aim thicknesses of the ASTM core-loss types are listed in Table 1.11.1.1 Thickness VariationsThe thickness m
43、easured atany location not less than 0.4 in. (10 mm) from an edge shallnot deviate more than 60.001 in. (60.025 mm) from theaverage thickness of the test lot or coil. The outer limits ofacceptable thickness of the ASTM core-loss type shall be asshown in Table 2.11.2 Width TolerancesThe width of mate
44、rial 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 3.11.3 Length TolerancesThe length dimension of cutlengths shall be as close as practicable to the ord
45、ered length.The maximum deviations from ordered length shall be asshown in Table 4.TABLE 2 Thickness TolerancesASTM Core-Loss Type Thickness Limits, in. (mm)18G041 0.0060-0.0080 (0.1520.203)23G045, 23H070, 23P060,23Q0540.0075-0.0100 (1.190-0.254)27G051, 27H074, 27P066,27Q0570.0095-0.0120 (0.241-0.30
46、5)30G058, 30H083, 30P070 0.0105-0.0130 (0.267-0.330)35G066, 35H094 0.0125-0.0150 (0.318-0.381)A87609311.4 Camber (Full-Width Coils)The deviation of a sideedge from a straight line over a 96-in. (2440-mm) length orfraction thereof shall not exceed 0.125 in. (3.2 mm).11.5 Out of Square (Cut Lengths)Th
47、e 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 0.0625 in./6 in. (1.6 mm/152 mm) of width or fractionthereof.12. Workmanship, Finish and Appearance12.1 Flatness:12.1.1 Sharp, short waves and buckl
48、es 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 require-ments for a degree of flatness more critical than that providedby the usual commercial prac
49、tices. Procedures for judging orevaluating the degree of flatness in such cases shall be subjectto negotiation between the user and the producer.12.2 Surface DefectsThe surface of the material shall bereasonably clean and essentially free from manufacturingdefects such as holes, mill marks, slivers, and so forth, whichwould interfere with its effective use in the intended applica-tion. The surface shall be free of loose dust and be compatiblewith immersion in the usual liquid transformer coolants.Applied surface coatings shall be reasonably thin, continuousin cover
