1、Designation: A 876 03Standard 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 (e) 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, gra
3、in-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 sil
4、icon 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 k
5、G (1.5 T) in accordance with Test Method A 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(1.7 T) in accordance with Test Method A 343/A 343M, and (4)l
6、aser-scribed 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,
7、 whichare 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 Altern
8、ating-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 Specifica
9、tionsA 700 Practices for Packaging, Marking, and LoadingMethods for Steel Products for Domestic 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 Test Method for Ductility of Orient
10、ed Electrical 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 Insu
11、lating Coatings by Composi-tion, Relative Insulating Ability and Application3. 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-oriented el
12、ectricalsteels 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 specification i
13、s 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 Oct. 1, 2003. Published November 2003. Originallyapproved in 1987. Last
14、previous edition approved in 1998 as A 876/A 876M 98.2For 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.1Copyrig
15、ht 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, Ty
17、peC-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 aninorgani
18、c 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 i
19、nherentC-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.TABLE 1 Core-Loss Type DesignationsConventional Grain-Oriented Electrical S
20、teelTested 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 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
21、.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 Accordance 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)
22、 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)High-Permeability Grain-Oriented Electrical SteelTested at 17 kG (1.7 T) in Accordance with Test Method A 343/A 343MASTMCore-LossTypeAAimThickne
23、ss,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-Scribed High-Permeability Grain-Oriented Electrical SteelTested at 17 kG (1.7 T) in Accordance with Test Methods A 804/A 804MASTMCore-LossTypeAAi
24、mThickness,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) 0.58 (1.28) 0.44 (0.97)ASee Practice A 664.BThese shall be the overall thicknesses as measured by contacting micrometrecaliper.CBased on parallel-grain Epstein specim
25、ens, stress-relief annealed aftershearing in accordance with 14.1.2.DBased on as-sheared parallel-grain sheet-type specimens. Stress-relief an-nealing will nullify the core-loss reduction produced by the laser scribing.A876032NOTE 1Additional description of surface coating Types C-2 and C-5is presen
26、ted in Specification A 345 and Classification A 976.5.2 Core-loss types having code letters P and 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 adequate
27、ly: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 ordere
28、d 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 stamped laminations, wound cores,bonded wound cores, formed lamination cores, welded lami-n
29、ation 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
30、 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 basic-oxygenor electric-furnace process.7.3 When changes in the manufacture of successive ship-
31、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 before shipment is made so that he can beafforded an opportunity to evaluate the effects.8. Mag
32、netic 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 confo
33、rmity 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 shal
34、l 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 180
35、0. 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
36、 treatment 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
37、with 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 differenttha
38、n 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 mater
39、ial 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 requir
40、es 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. Ductility ratings in the followingclasses are appropriate for grain-oriented steels in any thick-ness and condition when
41、tested at room temperature with abend 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 than
42、24 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 measu
43、red 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.A87603311.2 Width TolerancesThe width of m
44、aterial 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
45、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 96-in. (2440-mm) length orfraction thereof shall not exceed 0.125 in. (3.2 mm).11.5 Out of Square (Cut Lengths)The deviation of
46、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 buckles are extremel
47、y 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 practices. Procedur
48、es 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,
49、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 coverage, and tightly adherent.13. Sampling13.1 Each test lot shall be a single full-width coil constitut-ing the finished product of a single hot-rolled band processedunder essentially uniform conditions. The weight of a test lot istypically less than 20 000 lb (9000 kg). The producer shallassign a serial number to each
