ASTM_A_932_-_A_932M_-_01_2012.pdf

Designation:A932/A932M01(Reapproved 2012)Standard Test Method forAlternating-Current Magnetic Properties of AmorphousMaterials at Power Frequencies Using Wattmeter-Ammeter-Voltmeter Method with Sheet Specimens1This standard is issued under the fixed designation A932/A932M;the number immediately following the designation indicates the yearof original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers tests for various magneticproperties of flat-cast amorphous magnetic materials at powerfrequencies(50 and 60 Hz)using sheet-type specimens in ayoke-type test fixture.It provides for testing using eithersingle-or multiple-layer specimens.NOTE1This test method has been applied only at frequencies of 50and 60 Hz,but with proper instrumentation and application of theprinciples of testing and calibration embodied in the test method,it isbelieved to be adaptable to testing at frequencies ranging from 25 to400 Hz.1.2 This test method provides a test for specific core loss,specific exciting power and ac peak permeability at moderateand high flux densities,but is restricted to very soft magneticmaterials with dc coercivities of 0.07 Oe 5.57 A/m or less.1.3 The test method also provides procedures for calculatingac peak permeability from measured peak values of totalexciting currents at magnetic field strengths up to about 2 Oe159 A/m.1.4 Explanation of symbols and abbreviated definitionsappear in the text of this test method.The official symbols anddefinitions are listed in Terminology A340.1.5 This test method shall be used in conjunction withPractice A34/A34M.1.6 The values stated in either customary(cgs-emu andinch-pound)or SI units are to be regarded separately asstandard.Within 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.1.7 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 appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2A34/A34M Practice for Sampling and Procurement Testingof Magnetic MaterialsA340 Terminology of Symbols and Definitions Relating 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 FrameA876 Specification for Flat-Rolled,Grain-Oriented,Silicon-Iron,Electrical Steel,Fully Processed TypesA901 Specification for Amorphous Magnetic Core Alloys,Semi-Processed TypesA912/A912M Test Method for Alternating-Current Mag-netic Properties of Amorphous Materials at Power Fre-quencies Using Wattmeter-Ammeter-Voltmeter Methodwith Toroidal Specimens3.Terminology3.1 The definitions of terms,symbols,and conversion fac-tors relating to magnetic testing,used in this test method,arefound in Terminology A340.3.2 Definitions of Terms Specific to This Standard:3.2.1 sheet specimena rectangular specimen comprised ofa single piece of material or parallel multiple strips of materialarranged in a single layer.3.2.2 specimen stacktest specimens(as in 3.2.1)arrangedin a stack two or more layers high.4.Significance and Use4.1 This test method provides a satisfactory means ofdetermining various ac magnetic properties of amorphous1This test method is under the jurisdiction of ASTM Committee A06 onMagnetic Properties and is the direct responsibility of Subcommittee A06.01 on TestMethods.Current edition approved May 1,2012.Published July 2012.Originally approvedin 1995.Last previous edition approved in 2006 as A932/A932M01(2006).DOI:10.1520/A0932_A0932M-01R12.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 magnetic materials.It was developed to supplement the testingof toroidal and Epstein specimens.For testing toroidal speci-mens of amorphous materials,refer to Test Method A912/A912M.4.2 The procedures described herein are suitable for use bymanufacturers and users of amorphous magnetic materials formaterials specification acceptance and manufacturing control.NOTE2This test method has been principally applied to the magnetictesting of thermally,magnetically annealed,and flattened amorphous stripat 50 and 60 Hz.Specific core loss at 13 or 14 kG 1.3 or 1.4T,specificexciting power at 13 or 14 kG 1