1、Designation: E1476 04 (Reapproved 2014)Standard Guide forMetals Identification, Grade Verification, and Sorting1This standard is issued under the fixed designation E1476; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide is intended for tutorial purposes only. Itdescribes the general requirements, methods, and proceduresfor th
3、e nondestructive identification and sorting of metals.1.2 It provides guidelines for the selection and use ofmethods suited to the requirements of particular metals sortingor identification problems.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its
4、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. For specificprecautionary statements, see Section 10.2. Referenced Documents2.1 ASTM Standards:2E158 Practice for F
5、undamental Calculations to ConvertIntensities into Concentrations in Optical Emission Spec-trochemical Analysis (Withdrawn 2004)3E305 Practice for Establishing and Controlling AtomicEmission Spectrochemical Analytical CurvesE322 Test Method for Analysis of Low-Alloy Steels andCast Irons by Wavelengt
6、h Dispersive X-Ray FluorescenceSpectrometryE566 Practice for Electromagnetic (Eddy-Current) Sortingof Ferrous MetalsE572 Test Method forAnalysis of Stainless andAlloy Steelsby Wavelength Dispersive X-Ray Fluorescence Spectrom-etryE703 Practice for Electromagnetic (Eddy-Current) Sortingof Nonferrous
7、MetalsE977 Practice for Thermoelectric Sorting of ElectricallyConductive MaterialsF355 Test Method for ImpactAttenuation of Playing SurfaceSystems and MaterialsF1156 Terminology Relating to Product Counterfeit Protec-tion Systems (Withdrawn 2001)33. Terminology3.1 DefinitionsTerms used in this guide
8、 are defined in thestandards cited in Section 2 and in current technical literatureor dictionaries; however, because a number of terms that areused generally in nondestructive testing have meanings orcarry implications unique to metal sorting, they appear withexplanation in Appendix X1.4. Significan
9、ce and Use4.1 A major concern of metals producers, warehouses, andusers is to establish and maintain the identity of metals frommelting to their final application. This involves the use ofstandard quality assurance practices and procedures throughoutthe various stages of manufacturing and processing
10、, at ware-houses and materials receiving, and during fabrication and finalinstallation of the product. These practices typically involvestandard chemical analyses and physical tests to meet productacceptance standards, which are slow. Several pieces from aproduction run are usually destroyed or rend
11、ered unusablethrough mechanical and chemical testing, and the results areused to assess the entire lot using statistical methods. Statisticalquality assurance methods are usually effective; however,mixed grades, off-chemistry, and nonstandard physical proper-ties remain the primary causes for claims
12、 in the metalsindustry. A more comprehensive verification of product prop-erties is necessary. Nondestructive means are available tosupplement conventional metals grade verification techniques,and to monitor chemical and physical properties at selectedproduction stages, in order to assist in maintai
13、ning the identi-ties of metals and their consistency in mechanical properties.4.2 Nondestructive methods have the potential for monitor-ing grade during production on a continuous or statistical basis,for monitoring properties such as hardness and case depth, andfor verifying the effectiveness of he
14、at treatment, cold-working,and the like. They are quite often used in the field for solvingproblems involving off-grade and mixed-grade materials.1This guide is under the jurisdiction of ASTM Committee E07 on Nondestruc-tive Testing and is the direct responsibility of Subcommittee E07.10 on Speciali
15、zedNDT Methods.Current edition approved June 1, 2014. Published July 2014. Originally approvedin 1992. Last previous edition approved in 2010 as E1476 - 04(2010). DOI:10.1520/E1476-04R14.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at servicea
16、stm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19
17、428-2959. United States14.3 The nondestructive methods covered in this guide pro-vide both direct and indirect responses to the sample beingevaluated. Spectrometric analysis instruments respond to thepresence and percents of alloying constituents. The electro-magnetic (eddy current) and thermoelectr
18、ic methods, on theother hand, are among those that respond to properties in thesample that are affected by chemistry and processing, and theyyield indirect information on composition and mechanicalproperties. In this guide, the spectrometric methods are classi-fied as quantitative, whereas the metho
19、ds that yield indirectreadings are termed qualitative.4.4 This guide describes a variety of qualitative and quan-titative methods. It summarizes the operating principles of eachmethod, provides guidance on where and how each may beapplied, gives (when applicable) the precision and bias thatmay be ex
20、pected, and assists the investigator in selecting thebest candidates for specific grade verification or sorting prob-lems.4.5 For the purposes of this guide, the term “nondestruc-tive” includes techniques that may require the removal of smallamounts of metal during the examination, without affecting
21、 theserviceability of the product.4.6 The nondestructive methods covered in this guide pro-vide quantitative and qualitative information on metals prop-erties; they are listed as follows:4.6.1 Quantitative:4.6.1.1 X-ray fluorescence spectrometry, and4.6.1.2 Optical emission spectrometry.4.6.2 Qualit
22、ative:4.6.2.1 Electromagnetic (eddy current),4.6.2.2 Conductivity/resistivity,4.6.2.3 Thermoelectric,4.6.2.4 Chemical spot tests,4.6.2.5 Triboelectric, and4.6.2.6 Spark testing (special case).5. Background5.1 The standard quality assurance procedures for verifyingthe composition and physical propert
23、ies of a metal at aproducing facility are through chemical analysis and mechani-cal testing. These required tests result in the sacrifice of acertain amount of production for the preparation of samples,are costly and time-consuming, and may not provide timelyinformation regarding changes in product
24、quality. In a marketin which a single failure can result in heavy litigation anddamage costs, the manufacturer requires assurance that hisproduction will meet the customers acceptance standards.Nondestructive grade verification provides one means of moni-toring production to ensure that the product
25、will meet accep-tance requirements.5.2 Nondestructive methods may be used in conjunctionwith the accepted standard product quality tests to providecontinuous verification that current production lies within theagreed upon acceptance limits specified. In-line electromag-netic examinations may be used
26、 to indicate the consistency ofproduction. Any deviation from the norms set for the accep-tance band will result in automatic alarms, kick-out, or othermeans of alerting production personnel of a problem. Thusalerted, the mill can determine the cause for the alarm and takecorrective action. Portable
27、 optical emission spectrometry unitsmay be used to determine the concentrations of criticalelements without having to resort to slow physical and chemi-cal analyses. A quality assurance program combining conven-tional measurements with suitable nondestructive methods canprovide effective and timely
28、information on product composi-tion and physical properties. This will result in improvedquality and yield; savings in time, labor, and material; andreduced field failures and claims. This guide provides specificinformation regarding nondestructive metals identification,grade verification, and sorti
29、ng methods to assist in selecting theoptimum approach to solving specific needs.5.3 Spectrometric methods are capable of directly indicatingthe presence and percent of many of the elements thatcharacterize a metal grade. The spectrometric and thermoelec-tric techniques examine only the outermost sur
30、faces of thesample or material.As a result, for grade verification purposes,it may be necessary to grind sufficiently deep to ensure accessto the base metal for accurate readings. However, grinding mayaffect the thermoelectric response. The spectrometric methodsrequire physical contact and often som
31、e surface preparation.The electromagnetic method, however, does not require con-tact and very often is suited for on-line, automatic operation.The thermoelectric method, although requiring contact, re-sponds to many of the same parameters that influence theelectromagnetic responses. Both respond to
32、chemicalcomposition, processing, and treatments that affect the physicaland mechanical properties of the product. Nondestructivemethods for indicating the mechanical properties of a metal arebeyond the scope of this guide.5.4 Each method has particular advantages and disadvan-tages. The selection of
33、 suitable candidates for a specific gradeverification or sorting application requires an understanding ofthe technical operating features of each method. These includethe precision and bias necessary for the application andpractical considerations such as product configuration, surfacecondition, pro
34、duct and ambient temperatures, environmentalconstraints, etc.6. General Procedures6.1 Standardization/Calibration:6.1.1 Of primary concern in any materials identification orsorting program is delineation of the pertinent product charac-teristics (such as chemical composition, processing,configuratio
35、n, and physical properties) and the assignment ofacceptance limits to each. Often prescribed by materialsspecifications, they also may result from quality assuranceprocedures or by agreement between the producer and the user.6.1.2 Of equal importance is the selection of referencestandards. Quantitat
36、ive methods employ coupon standards thatare representative of the metals or alloy compositions to beverified, and the analytical instrumentation is standardizedagainst them. The indirect methods, particularly those thatrespond to physical properties as well as composition, requirereference standards
37、 that will represent the material specified incomposition, mechanical and physical properties, andE1476 04 (2014)2processing, as well as cover the means and extremes of theacceptance band. Coupon reference standards or product ref-erence standards, or both, may be selected as required.6.1.2.1 Coupon
38、 Reference StandardsThese are small, eas-ily handled metal panels made to specified chemical composi-tions. They are available commercially in sets, singly, or tospecification. They are useful for instrument standardization,determining separability among metals, and field use withportable equipment.
39、 They are not intended to reflect the effectsof processing or heat treatment on the acceptability of aproduct.6.1.2.2 Product Reference StandardsThese must representthe product specified in composition and mechanical andphysical properties. Ideally, three or more product referencestandards covering
40、the mean, plus two or more covering theextremes, should be obtained, suitably catalogued, and markedfor proper identification.6.1.3 Standardization or calibration procedures, or both, foreach method must be followed as specified by the instrumentmanufacturer. Coupon reference standards are used to s
41、tan-dardize and set up quantitative (spectrometric) or qualitative(thermoelectric and chemical spot test, etc.) verifications, aswell as for metals sorting checks on electromagnetic, electricalconductivity, and similar instruments. Rod, bar, wire, andtubular product reference standards are used almo
42、st exclusivelyfor the qualitative methods, such as the electromagnetic,electrical conductivity, triboelectric, and spark tests. These arefabricated from the product being manufactured, from sampleswith compositions and physical properties verified throughanalytical examinations.6.1.4 The known produ
43、ct reference standards used for thequalitative methods must be representative of the chemistry,processing, surface, and other physical and mechanical param-eters that might affect readings. Product standard parametersmust be verifiable.6.1.5 Coupon reference standards are useful for initialinstrumen
44、t adjustments, but final adjustments should be madeon standard samples verified as representative of good produc-tion pieces.6.1.6 Product standard samples will disclose potential errorsthat might result from surface alloy depletion, heavy oxidelayers, or hardness variations resulting from processin
45、g anoma-lies. Such known variables must be used to determine finalacceptance limits for any examination, and they will aidmaterially in both selecting a method and optimizing theexamination conditions.6.2 Test Piece Requirements:6.2.1 The relationship between the standard productsamples and pieces b
46、eing evaluated must be understoodclearly. This is of particular importance when using theelectromagnetic method. Composition, size, processing, sur-face condition, finish, straightness, and temperature must benominally the same as that represented by the standardsamples. To a lesser degree, this is
47、also true for the thermo-electric method. For the other methods, size, configuration, andmechanical processing usually do not affect composition read-ings to any significant degree.6.2.2 The means for performing the examination must becontrolled. If some surface metal removal is necessary (as it isf
48、or spectrometric examinations), the amount of removal, meansof removal, and removal location on the piece must bespecified and monitored closely. For electromagneticexaminations, the piece should be positioned in the samemanner relative to the coil as is the product standard sample.Failure to contro
49、l variables can result in the misidentification ofsamples.6.3 Display and Accept/Reject Criteria:6.3.1 Most systems employ some form of visual display orreadout to indicate the response to piece variables. Meterreadings, oscilloscope patterns, digital signals, and coloredspots (from a reagent in chemical spot testing) are typicalexamples. On instruments with digital or cathode ray tubedisplays, it is common practice to show the position and extentof adjustable gates for the setting of automatic alarm circuits.6.3.2 Automatic alarm gates may be positioned and adjustedto be triggere
