ASTM_A_900_-_A_900M_-_01_2012.pdf

Designation:A900/A900M01(Reapproved 2012)Standard Test Method forLamination Factor of Amorphous Magnetic Strip1This standard is issued under the fixed designation A900/A900M;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 measurements of laminationfactor(Note 1)of a specimen composed of strips cut fromamorphous magnetic material.It is suitable for the determina-tion of lamination factor for thin,flat case,metallic stripranging in width from 0.25 to 8.00 in.6.35 mm to 203 mmand in thickness from 0.0005 to 0.005 in.12.7 to 127 m.NOTE1Lamination factor is also termed space factor or stackingfactor.1.2 The values and equations stated in customary(egs-emuand inch-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.1.3 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.Summary of Test Method2.1 The laminated test specimen is oriented and aligned,then subjected to pressure in a compression device.Theresulting volume is then determined from the measured speci-men height,width,and length.An equivalent solid volume iscalculated from the specimen mass and the true density of thespecimen material.The ratio of the calculated(equivalentsolid)volume to the measured volume is the lamination factor.3.Significance and Use3.1 Lamination factor S indicates the deficiency of effectivematerial volume which is due to the presence of oxides,roughness,insulating coatings,and other conditions affectingthe strip surface.3.2 This test method is used to predict the fraction of metalthat is included in the volume of the firm coil wound from thespecimen tape.4.Interferences4.1 This test method is predicated on correctly aligned teststrips and uniform compression during test.Both of theseconditions are difficult to meet whenever the test specimenshave one or more elevated ridges running lengthwise along thesurface of the strip.4.2 This test method also presupposes that the test speci-mens are free from other defects,such as camber and waviness,that may affect the lamination factor.5.Apparatus5.1 MicrometersTwo types of micrometers are includedfor use in this test method as follows:5.1.1 Motor-Operated,Deadweight(Not Spring)ActuatedMicrometer,conforming to the following requirements:5.1.1.1 The micrometer shall be a deadweight digital-ordial-type micrometer,having two ground and lapped circularsurfaces with a capacity of not less than 0.030 in.0.75 mm.The movable face or presser foot shall have an area of 0.25 to0.33 in.2160 to 215 mm2 and corresponding to a diameter ofapproximately 0.56 to 0.65 in.14.2 to 16.5 mm.The fixedface or anvil shall be of such size that the whole area of thepresser foot is in contact with the anvil in the zero position.5.1.1.2 The surface shall be parallel to within 0.000 05 in.0.0012 mm and the presser foot shall move on an axisperpendicular to the anvil.5.1.1.3 The presser foot shall exert a steady pressure on thespecimen of 7.0 to 8.0 psi 48 to 55 kPa.5.1.1.4 A digital readout is preferred.If an analog gauge isused,the dial shall be at least 2 in.51 mm in diameter.It shallbe continuously graduated to read directly to 0.0001 in.0.0025 mm and shall be required with a telltale hand,ifnecessary,recording the number of complete revolutions of thelarge hand.5.1.1.5 The micrometer shall be capable of repeating itsreadings to 0.000 05 in.0.0012 mm at zero setting or on asteel gauge block.5.1.1.6 The deviations for the parts of the scale correspond-ing to the specimen thickness measured shall be applied ascorrections to the thickness reading.1This 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 1991.Last previous edition approved in 2006 as A900/A900M01(2006).DOI:10.1520/A0900_A0900M-01R12.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.1.1.7 The frame of the micrometer shall be of such rigiditythat a load of 3 lb 1.5 kg applied to the dial housing,out ofcontact with either the weight or the presser foot spindle,willproduce a deflection of the frame not greater than 0.0001 in.0.0025 mm,as indicated on the micro