1、Designation: A 1036 04Standard Guide forMeasuring Power Frequency Magnetic Properties of Flat-Rolled Electrical Steels Using Small Single Sheet Testers1This standard is issued under the fixed designation A 1036; the number immediately following the designation indicates the year oforiginal adoption
2、or, in the case of revision, 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 guide covers procedures for interpreting the spe-cific core loss and pe
3、ak permeability determined using smallsingle-sheet test systems. It is limited to single-sheet testsystems that require a test specimen or coupon be cut from thematerial being tested and are designed such that the entirewidth of that test specimen is magnetized during testing.1.2 This guide is prima
4、rily intended for measurements ofthe magnetic properties of flat-rolled electrical steels at fre-quencies of 50 Hz or 60 Hz under sinusoidal flux conditions.1.3 This guide includes procedures to provide correlationwith the 25-cm Epstein test method (Test Method A 343/A 343M).1.4 The range of magneti
5、c flux densities is governed by theproperties of the test specimens and the instruments and testpower source. Nonoriented electrical steels may be tested atmagnetic flux densities up to about 16-kG 1.6T for core loss.The maximum magnetic field strength for peak permeabilitytesting is limited by the
6、current carrying capacity of themagnetizing winding and the test power source. Single sheettesters are typically capable of testing at magnetic fieldstrengths up to 50 Oe 4000 A/m or more.1.5 Within this guide, a small single sheet tester (small SST)is defined as a magnetic tester designed to test f
7、lat, rectangularsheet-type specimens. Typical specimens for these testers aresquare (or nearly so). The design of the small SST test fixturemay be small enough to accommodate specimens about 5 by 5cm or may be large enough to accommodate specimens about36 by 36 cm. Specimens for a particular SST mus
8、t beappropriate for the particular test fixture.1.6 This guide covers two alternative test methods: Method1 and Method 2.1.6.1 Method 1 is an extension of Method 1 of Test MethodA 804/A 804M, which describes a test fixture having twowindings that encircle the test specimen and two low-reluctance, lo
9、w-core loss ferromagnetic yokes that serve as fluxreturn paths. The dimensions of the test fixture for Method 1are not fixed but rather may be designed and built for anynominal specimen dimension within the limits given in 1.5.The power loss in this case is determined by measuring theaverage value o
10、f the product of primary current and inducedsecondary voltage.1.6.2 Method 2 covers the use of a small single sheet tester,which employs a magnetizing winding, a magnetic flux sensingwinding, and a magnetic field strength detector. The power lossin this case is determined by measuring the average va
11、lue ofthe product of induced secondary voltage and magnetic fieldstrength.1.6.3 The calibration method described in the Annex of thisguide applies to both test methods.1.7 The values and equations stated in customary (cgs-emuand inch-pound) or SI units are to be regarded separately asstandard. Withi
12、n this standard, SI units are shown in brackets.The values stated in each system may not be exact equivalents;therefore, each system shall be used independently of the other.Combining values from the two systems may result in noncon-formance with this standard.1.8 This standard does not purport to a
13、ddress all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory requirements prior to use.2. Referenced Documents2.1 ASTM Standards:2A 34/A 34M
14、 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-Current Mag-netic Properties of Materials at Power Frequencies UsingWattmeter-Ammeter-Voltmeter Method and 25-cm Epste
15、inTest FrameA 677/A 677M Specification for Nonoriented ElectricalSteel Fully Processed TypesA 683/A 683M Specification for Nonoriented ElectricalSteel, Semiprocessed Types1This guide is under the jurisdiction of ASTM Committee A06 on MagneticProperties and is the direct responsibility of Subcommitte
16、e A06.01 on Test Methods.Current edition approved May 1, 2004. Published May 2004.2For 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 pag
17、e onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.A 726 Specification for Cold-Rolled Magnetic LaminationQuality Steel, Semiprocessed TypesA 804/A 804M Test Methods for Alternating-Current Mag-netic Properties of M
18、agnetic at Power Frequencies UsingSheet-Type Test SpecimensA 840/A 840M Specification for Fully Processed MagneticLamination Steel3. Terminology3.1 Definitions:3.1.1 GeneralThe definitions of terms, symbols, and con-version factors relating to magnetic testing found in Terminol-ogy A 340 are used in
19、 these methods.3.2 Definitions of Terms Specific to This Standard:3.2.1 sheet specimena rectangular specimen comprised ofa single piece of material or paralleled multiple strips ofmaterial arranged in a single layer.3.2.2 small single sheet testera magnetic tester designedto determine the magnetic p
20、roperties of small rectangularsheet-type specimens.4. Significance and Use4.1 Materials EvaluationSmall single sheet testers weredeveloped to supplement the testing of Epstein specimens forvarious applications. They are especially appropriate for deter-mining the magnetic properties of samples when
21、insufficientmaterial is available for preparation of an Epstein specimen.Although the small specimen size is attractive, the precision ofthe small sheet testers is not expected to be as good as that ofthe test method Test Method A 343/A 343M. Small sheettesters are frequently used to measure the pro
22、perties of bothfully processed and semiprocessed nonoriented and magneticlamination steels. Specimens of semiprocessed steels are nor-mally subjected to an appropriate quality development annealprior to testing. Small sheet testers may also be used toevaluate oriented electrical steels in either the
23、 as sheared orstress-relief annealed condition.5. Apparatus5.1 Test Method 1The apparatus for Test Method 1includes a test fixture having two windings that encircle the testspecimen (a magnetizing winding and a flux-sensing secondarywinding) and two low-reluctance, low-core loss ferromagneticyokes t
24、hat serve as flux return paths. Such a test fixture may beconstructed by following the instructions given in Annex A1 ofTest Method A 804/A 804M. The test power and instrumenta-tion for this method are described as Test Method 1 in TestMethod A 804/A 804M. The primary difference between thetests cov
25、ered by this guide and Test Method 1 of Test MethodA 804/A 804M are the dimensions of the yokes and thelimitation to the use of double-yoke test fixtures. Whenselecting test instrumentation and test power source compo-nents for Method 1, the devices selected for use with smallsingle-sheet test fixtu
26、res must have appropriate ranges for thesesmaller test fixtures.5.2 Test Method 2Test systems for Method 2 are suppliedas complete test systems: test fixture, test power source, andcomplete instrumentation.6. Procedure6.1 Determine Correction FactorsFollowing the proce-dures given in Annex A1, deter
27、mine correction factors for thegrades of material that will be evaluated at the magnetic fluxdensities at which tests will be performed. The samples used todetermine the correction factors must be typical of the materialthat will be evaluated since correction factors vary with class ofmaterial, chem
28、ical composition, thickness, heat treatment,grain direction, magnetic flux density, and other physicalproperties.6.2 Prepare the Test SpecimenThe type of test fixture andits dimensions govern the dimensions of permissible testspecimens. The minimum length of a specimen shall be no lessthan the outsi
29、de dimension of the distance between pole facesof the test fixture. The amount of projection of the specimenbeyond the pole faces of fixture is not critical but should be nolonger than necessary for convenient loading and unloading ofthe specimen. For maximum accuracy, the specimen widthshould, as n
30、early as practicable, be the maximum that can beaccommodated by the opening of the test coil. As a minimum,it is recommended that the specimen width be at least one halfof the maximum width that can be accommodated by the testcoil.6.2.1 Specimens with length and width appropriate for thesmall single
31、 sheet tester shall be cut by a suitable method. Thespecimens shall be as rectangular as practicable. Excessiveburr and mechanical distortion must be avoided when prepar-ing the test specimens. Specimens may be subjected to anydesired heat treatment.6.3 Make Initial DeterminationsDepending upon the
32、testequipment used, the appropriate measured values of length,width, thickness, and/or mass of the specimen must be deter-mined prior to conducting magnetic tests. These measuredvalues are needed to set up the instrument for conducting tests.When mass is required, it shall be determined using a bala
33、ncecapable of measuring the specimen mass with an uncertaintyless than 0.1 %. The length or width of the specimen shall bemeasured by any suitable method with an uncertainty less than0.1 %.6.3.1 Cross-sectional AreaThe preferred method of deter-mining cross-sectional area is the mass-density method.
34、 Sometest systems may require that the width and thickness of thespecimen be entered into the test instrument and others mayrequire that the cross-sectional area be entered. The cross-sectional area is determined using the following equation:A 5 m/ld! (1)where:A = cross-sectional area of specimen, c
35、m2,m = total mass of specimen, g,l = actual length of specimen, cm, andd = assumed density of specimen material, g/cm3.When required, the thickness may be determined by dividingthe cross-sectional area by the width.6.3.2 Alternate Cross-sectional AreaAlthough the mass-density method of determining t
36、he cross-sectional area is thepreferred method, direct measurement of the thickness andwidth of the test specimen is an alternate method. When theA1036042thickness is measured directly with a micrometer, the length ofthe specimen does not need to be measured. Direct measure-ment of the thickness is
37、likely to increase the uncertainty ofmeasurements, especially for specimens that have appliedcoatings, have rough surfaces, or are very thin (less than about0.018 in 0.50 mm). If direct thickness measurement is usedwhen testing specimens, direct thickness measurement shouldalso be used when making m
38、easurements with the small sheettester to determine calibration constants (the correspondingEpstein tests are always to be conducted according to TestMethod A 343/A 343M).6.4 Perform Tests:6.4.1 Method 1Follow the procedures for conducting testsaccording to Sections 9 though 11 of Test Method A 804/
39、A 804M to determine the uncorrected core losses or uncor-rected magnetic field strengths, or both, at the desired fluxdensities. When computing the uncorrected core loss anduncorrected magnetic field strength, the effective path lengthshould be the distance between the inner edges of the flux-return
40、 yokes measured in the direction of the flux path in thetest specimen.6.4.2 Method 2Follow the instrument manufacturers in-structions to determine the uncorrected core losses or uncor-rected magnetic field strengths, or both, at the desired fluxdensities.6.5 Apply Correction FactorsUsing the appropr
41、iate cor-rection factors for the test specimen and test magnetic fluxdensity, correct the uncorrected core losses and uncorrectedmagnetic field strengths determined using the small single-sheet tester (according to either Method 1 or Method 2) usingthe equations below:PCB;!5 KlPa(2)where:PC(B;)= cor
42、rected specific core loss, W/lb W/kg,Kl= correction factor for core loss at specified testconditions, andPa= uncorrected specific core loss by yoke fixturetest, W/lb W/kg.HP5 K2Ha(3)where:HP= corrected peak magnetic field strength, Oe A/m,K2= correction factor for magnetic field strength at speci-fi
43、ed test conditions, andHa= uncorrected peak magnetic field strength by yokefixture test, Oe A/m.7. Keywords7.1 alternating current; core loss; electrical steel; flux den-sity; magnetic; magnetic material; magnetic test; permeability;power frequency; sheetANNEXES(Mandatory Information)A1. CALIBRATION
44、 OF SMALL SINGLE SHEET TESTERS (SSTs)A1.1 This calibration procedure uses specimens that aresuitable for testing using a 25-cm Epstein frame. Thesespecimens are composed of strips that are typically longer thanthe normal test specimen for the SST being calibrated. Thesingle sheet testers described i
45、n both methods discussed in thisguide are considered to be insensitive to excess specimenlength. If the specimens are longer than the distance betweenthe outside edges of the yoke, the portion of the specimen thatextends beyond the yoke should be supported to avoid stress.A1.2 The specimens used to
46、calibrate the SST shall consistof strips typical of the grade of material that is to be tested inthe SST. At least five specimens of each grade are preferred.For oriented materials these specimens shall be stress-reliefannealed. For nonoriented materials, the annealed condition ofthe calibration spe
47、cimens shall be the same as that of thematerial to be tested. The width of each strip shall be 3.0 cm30 mm. The minimum length of each specimen shall be 28cm 280 mm. The number of strips in each specimen shall bea multiple of four and a minimum of twelve.A1.3 Each specimen shall be tested in a 25-cm
48、 Epsteinframe in accordance with test method Test Method A 343/A 343M. The magnetic properties to be determined are thosewhich the SST will be used to measure routinely whencalibrated.A1.4 Each specimen shall be tested in the SST. A maximumof 12 strips (limited by test fixture) may be combined inpar
49、allel in a single layer when tested in the SST. Dependingupon the outside dimension of the distance between the yokefaces of the SST test fixture, tests may be required at more thanone position along the length of the specimen to permitevaluation of the average properties.A1.5 When conducting tests using equipment described inMethod 1, an effective magnetic path length must be assumedfor calculating the uncorrected specific core loss from mea-sured total power loss. The preferred assumed effective pathlength is the distance between the inner edges of
