ASTM_E_112_-_13.pdf

Designation:E11213Standard Test Methods forDetermining Average Grain Size1This standard is issued under the fixed designation E112;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,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.This standard has been approved for use by agencies of the U.S.Department of Defense.INTRODUCTIONThese test methods of determination of average grain size in metallic materials are primarilymeasuring procedures and,because of their purely geometric basis,are independent of the metal oralloy concerned.In fact,the basic procedures may also be used for the estimation of average grain,crystal,or cell size in nonmetallic materials.The comparison method may be used if the structure ofthe material approaches the appearance of one of the standard comparison charts.The intercept andplanimetric methods are always applicable for determining average grain size.However,thecomparison charts cannot be used for measurement of individual grains.1.Scope1.1 These test methods cover the measurement of averagegrain size and include the comparison procedure,the planim-etric(or Jeffries)procedure,and the intercept procedures.These test methods may also be applied to nonmetallicmaterials with structures having appearances similar to those ofthe metallic structures shown in the comparison charts.Thesetest methods apply chiefly to single phase grain structures butthey can be applied to determine the average size of a particulartype of grain structure in a multiphase or multiconstituentspecimen.1.2 These test methods are used to determine the averagegrain size of specimens with a unimodal distribution of grainareas,diameters,or intercept lengths.These distributions areapproximately log normal.These test methods do not covermethods to characterize the nature of these distributions.Characterization of grain size in specimens with duplex grainsize distributions is described in Test Methods E1181.Mea-surement of individual,very coarse grains in a fine grainedmatrix is described in Test Methods E930.1.3 These test methods deal only with determination ofplanar grain size,that is,characterization of the two-dimensional grain sections revealed by the sectioning plane.Determination of spatial grain size,that is,measurement of thesize of the three-dimensional grains in the specimen volume,isbeyond the scope of these test methods.1.4 These test methods describe techniques performedmanually using either a standard series of graded chart imagesfor the comparison method or simple templates for the manualcounting methods.Utilization of semi-automatic digitizingtablets or automatic image analyzers to measure grain size isdescribed in Test Methods E1382.1.5 These test methods deal only with the recommended testmethods and nothing in them should be construed as definingor establishing limits of acceptability or fitness of purpose ofthe materials tested.1.6 The measured values are stated in SI units,which areregarded as standard.Equivalent inch-pound values,whenlisted,are in parentheses and may be approximate.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.1.8 The paragraphs appear in the following order:SectionNumberScope1Referenced Documents2Terminology3Significance and Use4Generalities of Application5Sampling6Test Specimens7Calibration8Preparation of Photomicrographs9Comparison Procedure10Planimetric(Jeffries)Procedure11General Intercept Procedures12Heyn Linear Intercept Procedure13Circular Intercept Procedures14Hilliard Single-Circle Procedure14.21These test methods are under the jurisdiction of ASTM Committee E04 onMetallography and are the direct responsibility of Subcommittee E04.08 on GrainSize.Current edition approved Oct.1,2013.Published February 2014.Originallyapproved in 1955.Last previous edition approved 2012 as E112 12.DOI:10.1520/E0112-13.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 Abrams Three-Circle Procedure14.3Statistical Analysis15Specimens with Non-equiaxed Grain Shapes16Specimens Containing Two or More Phases or Constituents17Report18Precision and Bias19Keywords20Annexes:Basis of ASTM Grain Size NumbersAnnexA1Equations for Conversions Among Various Grain Size MeasurementsAnnexA2Austenite Grain Size,Ferritic and Austenitic SteelsAnnexA3Fracture Grain Size MethodAnnexA4Requirements for Wrought Copper and Copper-Base AlloysAnnexA5Application to Special SituationsAnnexA6Appendixes:Results of Interlaboratory Grain Size DeterminationsAppendixX1Referenced AdjunctsAppendixX22.Referenced Documents2.1 ASTM Standards:2E3 Guide for