1、Designation: E 45 053Standard Test Methods forDetermining the Inclusion Content of Steel1This standard is issued under the fixed designation E 45; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of last revision. A number
2、in parentheses indicates the year of last reapproval. A superscriptepsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1NOTETable 1 was editorially corrected in February 2007.2NOTESections 15.
3、2.2 and 18.5 were editorially corrected in June 2008.3NOTE12.3.1 and Figure 4 were editorially corrected in September 2009.1. Scope1.1 These test methods cover a number of recognizedprocedures for determining the nonmetallic inclusion contentof wrought steel. Macroscopic methods include macroetch,fr
4、acture, step-down, and magnetic particle tests. Microscopicmethods include five generally accepted systems of examina-tion. In these microscopic methods, inclusions are assigned toa category based on similarities in morphology, and notnecessarily on their chemical identity. Metallographic tech-nique
5、s that allow simple differentiation between morphologi-cally similar inclusions are briefly discussed. While the meth-ods are primarily intended for rating inclusions, constituentssuch as carbides, nitrides, carbonitrides, borides, and interme-tallic phases may be rated using some of the microscopic
6、methods. In some cases, alloys other than steels may be ratedusing one or more of these methods; the methods will bedescribed in terms of their use on steels.1.2 This practice covers procedures to perform JK-typeinclusion ratings using automatic image analysis in accordancewith microscopic methods A
7、 and D.1.3 Depending on the type of steel and the propertiesrequired, either a macroscopic or a microscopic method fordetermining the inclusion content, or combinations of the twomethods, may be found most satisfactory.1.4 These test methods deal only with recommended testmethods and nothing in them
8、 should be construed as definingor establishing limits of acceptability for any grade of steel.1.5 The values stated in SI units are to be regarded as thestandard. Values in parentheses are conversions and are ap-proximate.1.6 This standard does not purport to address all of thesafety concerns, if a
9、ny, 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:2D96 Test Method for Water and Sediment in Crude O
10、il byCentrifuge Method (Field Procedure)E3 Guide for Preparation of Metallographic SpecimensE7 Terminology Relating to MetallographyE 381 Method of Macroetch Testing Steel Bars, Billets,Blooms, and ForgingsE 709 Guide for Magnetic Particle ExaminationE 768 Practice for Preparing and Evaluating Speci
11、mens forAutomatic Inclusion Assessment of SteelE 1245 Practice for Determining Inclusion or Second-PhaseConstituent Content of Metals by Automatic Image Analy-sisE 1444 Practice for Magnetic Particle ExaminationE 1951 Guide for Calibrating Reticles and Light Micro-scope Magnifications2.2 SAE Standar
12、ds:3J422, Recommended Practice for Determination of Inclu-sions in Steel2.3 Aerospace Material Specifications:3AMS 2300, Premium Aircraft-Quality Steel Cleanliness:Magnetic Particle Inspection ProcedureAMS 2301, Aircraft Quality Steel Cleanliness: MagneticParticle Inspection ProcedureAMS 2303, Aircr
13、aft Quality Steel Cleanliness: MartensiticCorrosion-Resistant Steels Magnetic Particle InspectionProcedureAMS 2304, Special Aircraft-Quality Steel Cleanliness:1These test methods are under the jurisdiction of ASTM Committee E04 onMetallography and is the direct responsibility of Subcommittee E04.09
14、on Inclu-sions.Current edition approved Nov. 1, 2005. Published December 2005. Originallyapproved in 1942. Last previous edition approved in 2002 as E 45 97 (2002).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Boo
15、k of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from Society of Automotive Engineers (SAE), 400 CommonwealthDr., Warrendale, PA 15096-0001.1Copyright ASTM International. 100 Barr Harbor Drive P.O. box C-700 West Conshohocken, Pennsylv
16、ania 19428-2959, United StatesCopyright by ASTM Intl (all rights reserved); Tue Oct 27 02:45:38 EDT 2009Downloaded/printed byGuo Dehua (CNIS) pursuant to License Agreement. No further reproductions authorized.Magnetic Particle Inspection Procedure2.4 ISO Standards:4ISO 3763, Wrought SteelsMacroscopi
17、c Methods for As-sessing the Content of Nonmetallic InclusionsISO 4967, SteelDetermination of Content of NonmetallicInclusionsMicrographic Methods Using Standard Dia-grams2.5 ASTM Adjuncts:Inclusions in Steel Plates I-r and II5Four Photomicrographs of Low Carbon Steel63. Terminology3.1 Definitions:3
18、.1.1 For definitions of terms used in this practice, seeTerminology E7.3.1.2 Terminology E7 includes the term inclusion count;since some methods of these test methods involve lengthmeasurements or conversions to numerical representations oflengths or counts, or both, the term inclusion rating ispref
19、erred.3.2 Definitions of Terms Specific to This Standard:3.2.1 aspect ratiothe length-to-width ratio of a micro-structural feature.3.2.2 discontinuous stringerthree or more Type B or Cinclusions aligned in a plane parallel to the hot working axisand offset by no more than 15 m, with a separation of
20、less than40 m (0.0016 in.) between any two nearest neighbor inclu-sions.3.2.3 inclusion typesfor definitions of sulfide-, alumina-,and silicate-type inclusions, see Terminology E 7. Globularoxide, in some methods refers to isolated, relatively nonde-formed inclusions with an aspect ratio not in exce
21、ss of 2:1. Inother methods, oxides are divided into deformable and nonde-formable types.3.2.4 JK inclusion ratinga method of measuring nonme-tallic inclusions based on the Swedish Jernkontoret procedures;Methods A and D of these test methods are the principal JKrating methods, and Method E also uses
22、 the JK rating charts.3.2.5 stringeran individual inclusion that is highly elon-gated in the deformation direction or three or more Type B orC inclusions aligned in a plane parallel to the hot working axisand offset by no more than 15 m, with a separation of less than40 m (0.0016 in.) between any tw
23、o nearest neighbor inclu-sions.3.2.6 threshold settingisolation of a range of gray levelvalues exhibited by one constituent in the microscope field.3.2.7 worst-field ratinga rating in which the specimen israted for each type of inclusion by assigning the value for thehighest severity rating observed
24、 of that inclusion type any-where on the specimen surface.4. Significance and Use4.1 These test methods cover four macroscopic and fivemicroscopic test methods (manual and image analysis) fordescribing the inclusion content of steel and procedures forexpressing test results.4.2 Inclusions are charac
25、terized by size, shape, concentra-tion, and distribution rather than chemical composition. Al-though compositions are not identified, Microscopic methodsplace inclusions into one of several composition-related cat-egories (sulfides, oxides, and silicatesthe last as a type ofoxide). Paragraph 12.2.1
26、describes a metallographic techniqueto facilitate inclusion discrimination. Only those inclusionspresent at the test surface can be detected.4.3 The macroscopic test methods evaluate larger surfaceareas than microscopic test methods and because examinationis visual or at low magnifications, these me
27、thods are best suitedfor detecting larger inclusions. Macroscopic methods are notsuitable for detecting inclusions smaller than about 0.40 mm(164 in.) in length and the methods do not discriminateinclusions by type.4.4 The microscopic test methods are employed to charac-terize inclusions that form a
28、s a result of deoxidation or due tolimited solubility in solid steel (indigenous inclusions). Theseinclusions are characterized by morphological type, that is, bysize, shape, concentration, and distribution, but not specificallyby composition. The microscopic methods are not intended forassessing th
29、e content of exogenous inclusions (those fromentrapped slag or refractories).4.5 Because the inclusion population within a given lot ofsteel varies with position, the lot must be statistically sampledin order to assess its inclusion content. The degree of samplingmust be adequate for the lot size an
30、d its specific characteristics.Materials with very low inclusion contents may be moreaccurately rated by automatic image analysis, which permitsmore precise microscopic ratings.4.6 Results of macroscopic and microscopic test methodsmay be used to qualify material for shipment, but these testmethods
31、do not provide guidelines for acceptance or rejectionpurposes. Qualification criteria for assessing the data devel-oped by these methods can be found in ASTM productstandards or may be described by purchaser-producer agree-ments. By agreements between producer and purchaser, thispractice may be modi
32、fied to count only certain inclusion typesand thicknesses, or only those inclusions above a certainseverity level, or both. Also, by agreement, qualitative prac-tices may be used where only the highest severity ratings foreach inclusion type and thickness are defined or the number offields containin
33、g these highest severity ratings are tabulated.4.7 These test methods are intended for use on wroughtmetallic structures. While a minimum level of deformation isnot specified, the test methods are not suitable for use on caststructures or on lightly worked structures.4.8 Guidelines are provided to r
34、ate inclusions in steelstreated with rare earth additions or calcium-bearing com-pounds. When such steels are evaluated, the test report shoulddescribe the nature of the inclusions rated according to eachinclusion category (A, B, C, D).4.9 In addition to the Practice E 45 JK ratings, basic (suchas u
35、sed in Practice E 1245) stereological measurements (forexample, the volume fraction of sulfides and oxides, thenumber of sulfides or oxides per square millimeter, the spacing4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.5Available from AST
36、M Headquarters. Order ADJE004502.6Available from ASTM Headquarters. Order ADJE004501.E450532Copyright by ASTM Intl (all rights reserved); Tue Oct 27 02:45:38 EDT 2009Downloaded/printed byGuo Dehua (CNIS) pursuant to License Agreement. No further reproductions authorized.between inclusions, and so fo
37、rth) may be separately deter-mined and added to the test report, if desired for additionalinformation. This practice, however, does not address themeasurement of such parameters.MACROSCOPIC METHODS5. Macroscopical Test Methods Overview5.1 Summary:5.1.1 Macro-etch TestThe macro-etch test is used toin
38、dicate inclusion content and distribution, usually in the crosssection or transverse to the direction of rolling or forging. Insome instances, longitudinal sections are also examined. Testsare prepared by cutting and machining a section through thedesired area and etching with a suitable reagent. A
39、solution ofone part hydrochloric acid and one part water at a temperatureof 71 to 82C (160 to 180F) is widely used. As the name ofthis test implies, the etched surface is examined visually or atlow magnification for inclusions. Details of this test areincluded in Method E 381. The nature of question
40、able indica-tions should be verified by microscopic examination or othermeans of inspection.5.1.1.1 Sulfides are revealed as pits when the standardetchant described in 5.1.1 is used.5.1.1.2 Only large oxides are revealed by this test method.5.1.2 Fracture TestThe fracture test is used to determineth
41、e presence and location of inclusions as shown on thefracture of hardened slices approximately 9 to 13 mm (38 to12in.) thick. This test is used mostly for steels where it is possibleto obtain a hardness of approximately 60 HRC and a fracturegrain size of 7 or finer. Test specimens should not haveexc
42、essive external indentations or notches that guide thefracture. It is desirable that fracture be in the longitudinaldirection approximately across the center of the slice. Thefractured surfaces are examined visually and at magnificationsup to approximately ten diameters, and the length and distri-bu
43、tion of inclusions is noted. Heat tinting, or blueing, willincrease visibility of oxide stringers. ISO 3763 provides a chartmethod for fracture surface inclusion ratings. In some in-stances, indications as small as 0.40 mm (164 in.) in length arerecorded.5.1.3 Step-Down MethodThe step-down test meth
44、od isused to determine the presence of inclusions on machinedsurfaces of rolled or forged steel. The test sample is machinedto specified diameters below the surface and surveyed forinclusions under good illumination with the unaided eye orwith low magnification. In some instances, test samples arema
45、chined to smaller diameters for further examination after theoriginal diameters are inspected. This test is essentially used todetermine the presence of inclusions 3 mm (18 in.) in lengthand longer.5.1.4 Magnetic Particle MethodThe magnetic particlemethod is a variation of the step-down method for f
46、erromag-netic materials in which the test sample is machined, magne-tized, and magnetic powder is applied. Discontinuities as smallas 0.40 mm (164 in.) in length create magnetic leakage fieldsthat attract the magnetic powder, thereby outlining the inclu-sion. See Practice E 1444 and Guide E 709 on m
47、agneticparticle examinations for more details of the procedure. Referto Aerospace Materials Specifications AMS 2300, AMS 2301,AMS 2303, and AMS 2304.5.2 Advantages:5.2.1 These test methods facilitate the examination of speci-mens with large surface areas. The larger inclusions in steel,which are the
48、 main concern in most cases, are not uniformlydistributed and the spaces between them are relatively large, sothat the chances of revealing them are better when largerspecimens are examined.5.2.2 Specimens for macroscopic examination may bequickly prepared by machining and grinding.Ahighly polisheds
49、urface is not necessary. The macroscopic methods are suffi-ciently sensitive to reveal the larger inclusions.5.3 Disadvantages:5.3.1 These test methods do not distinguish among thedifferent inclusion shapes.5.3.2 They are not suitable for the detection of smallglobular inclusions or of chains of very fine elongated inclu-sions.5.3.3 The magnetic particle method can lead to incorrectinterpretation of microstructural features such as streaks ofretained austenite, microsegregation, or carbides in certainalloys; this is particularly likely if high mag
